2018 Tailings Research Projects Annual Report FINAL 03Jun2019 › sites › default › files › attachments... · Create a cap-isolating layer with a water cap in place Sand capping

COSIATAILINGSEPA–2018TAILINGSRESEARCHREPORT i

IntroductionThis report summarizes the recent progress for Canada’s Oil Sands Innovation Alliance (COSIA) TailingsEnvironmental Priority Area (EPA) tailings research projects. Tailings are the sand, silt, clay, and water foundnaturallyinoilsandsthatremainfollowingtheminingandbitumenextractionprocess.MembercompanieswiththeCOSIATailingsEPAarefocusedonimprovingthemanagementofoilsandstailingsthroughouttheirproductionandtreatment,storage,reclamationandclosurephases.

Workingwithuniversities,governmentandresearchinstitutes,othercompaniesandpartners,theCOSIATailingsEPAisbringingtogetherthesharedexperience,expertiseandfinancialcommitmentofoilsandsminingcompaniestofindnewtechnologiesandsolutionstotailingsmanagement.

The Tailings EPA has identified key issues facing the industry and is working to address them. The key issuesinclude:

• accumulation of fluid fine tailings (FFT) within tailings ponds through the development of new andimprovedtailingsmanagementtechnologies;

• treatmentofprocessaffectedwater,thewaterwhichremainsoncetheFFTareremoved;and

• accelerationof reclamationof the resulting tailings deposits so that they canbe incorporated into thefinalreclaimedclosurelandscape.

The research projects summarized in this report are categorized into four principal research areas: tailingscapping, tailings treatment technologies, froth treatment tailings, and consolidation modelling. Each researchproject seeks to advance the understanding of, and improve upon, the risks and uncertainties with tailingsmanagement.

Tailings deposits can have very different properties: from sand-dominated deposits to thin and thick lift fines-dominated deposits; deposits that will underlie the water column in pit lakes; and tailings mixed with othermaterials like overburden. Reclamation of most tailings deposits occurs some time after deposition, sounderstandingthedesiredpropertiesoftreatedtailingsrequiresanunderstandingofthefactorsthatshortenorlengthen the time for consolidation after the deposit is placed. For both tailings treatment processes andconsolidationmechanisms,theindustryisseekingabetterunderstandingsothatthisknowledgecanbeappliedtoenhancereclamationandclosureplanningandimplementation.

Predictingtrajectoriesoftailingsdepositsthroughmodellingcanreduceuncertaintyandaidinthedevelopmentofrobust reclamation and closure plans. Another area of research is the acquisition of real-time tailings processinformation.In-lineorat-lineanalyzerscanprovideinformationontheefficacyofthetailingstreatment.

ThisinauguralsummaryreportfromtheCOSIATailingsEPAmembercompanieshighlightsjustsomeoftherecentresearchworkintailingsmanagementatvariousstagesofresearch—fromliteraturereviews,laboratoryprojects,pilottrialsandtolarge,fieldscaledemonstrationandcommercializationprograms.

COSIATAILINGSEPA–2018TAILINGSRESEARCHREPORT ii

PleasecontacttheIndustryChampionidentifiedforeachresearchprojectforadditionalinformation.InformationonmanyoftheprojectsisalsoavailableontheCOSIAwebsite(https://www.cosia.ca).

Permission for non-commercial use, publication or presentation of excerpts or figures is granted, providedappropriateattributioniscited.Commercialreproduction,inwholeorinpart,isnotpermitted.

The use of thesematerials by the end user is donewithout any affiliationwith or endorsement by any COSIAmember,andisatthesoleriskoftheenduser.

Thisreportwaspreparedandfundedby:

CanadianNaturalResourcesLimitedImperialSuncorEnergyInc.SyncrudeCanadaLtd.TeckResourcesLimited

COSIATAILINGSEPA–2018TAILINGSRESEARCHREPORT iii

TableofContentsIntroduction................................................................................................................................................................i

TableofContents.....................................................................................................................................................iii

TailingsCapping.........................................................................................................................................................1

SuppressionofFinesRe-suspensioninAqueousDepositionofTailings..................................................................2

SurfaceStrengtheningofaSoftDeposit..................................................................................................................5

LiteratureReviewforIn-line/On-lineRheologyMonitoringTechnology.................................................................8

TailingsTreatmentTechnologies..........................................................................................................................10

FinesMeasurementWorkingGroup......................................................................................................................11

Long-termDewateringofAmendedOilSandsTailings..........................................................................................14

MicrobiologicalandVegetationforTailingsManagement(BugsandVeggies).....................................................19

OptimizingtheUseofTubifextoEnhanceDensificationandStrengthofOilSandsTailings:BuildingonRecentLaboratoryTestSuccess,TowardsPilot.................................................................................................................23

DevelopmentofRapidScreeningMethodsforMatureFineTailings.....................................................................27

PotentialApplicationofVoluteScrewPressFiltertoTreatOilSandsFluidFineTailings–Phase2......................35

MatureFineTailingsSpikingofHorizonThickeners...............................................................................................38

ThickenedTailingsRe-flocculationandMixingTests.............................................................................................41

AcceleratedFluidFineTailingsConsolidationwithElectrokinetics........................................................................44

ClayRemovalfromFluidFineTailings....................................................................................................................47

EngineeredTailingsResearch.................................................................................................................................49

AlternativePolymersforMatureFineTailings(MFT)Drying.................................................................................51

ThickenerOperationOptimization.........................................................................................................................53

PermanentAquaticStorageStructureforFluidFineTailings.................................................................................57

MatureFineTailingsPolymerInjectorRedesign....................................................................................................60

OutotecPSI500i®InstrumentFieldTest.................................................................................................................62

PilotScaleTestProgramofNon-SegregatingTailingsEnhancement.....................................................................66

FluidFineTailingsIn-lineFlocculationandCo-deposition.....................................................................................69

AcceleratedDewatering/RimDitching.................................................................................................................73

MixingCoarseTailingsintoInsituFineTailings:LiteratureandOperationalCaseStudyReview.........................75

COSIATAILINGSEPA–2018TAILINGSRESEARCHREPORT iv

GeobagsPilotStudy................................................................................................................................................77

PressureFiltrationforFluidFineTailingsTreatment.............................................................................................79

ManagingTailingsfromtheCreatingValuefromWasteProcess..........................................................................81

FrothTreatmentTailings........................................................................................................................................83

FrothTreatmentTailingsEvaluation......................................................................................................................84

MinimizationofGreenhouseGasEmissionsinFrothTreatmentTailingsbyManipulationofElectronAcceptors87

ConsolidationModelling........................................................................................................................................90

NSERC/COSIAIndustrialChairinOilSandsTailingsGeotechnique........................................................................91

ImpactofBitumenonTailingsConsolidation.......................................................................................................113

AResearchTrajectoryTowardsImprovingFinesCapturePrediction–Verification,ApplicationandImprovementofDelft3D.............................................................................................................................................................115

LimitationstotheGeotechnicalPropertiesofPolymer-TreatedFluidFineTailings............................................118

TailingsConsolidationMechanisms.....................................................................................................................121

InSituRealTimeMeasurementsofSolidsContentinSettlingTailings...............................................................125

ConversionofOilSandsBy-productstoClosureLandforms................................................................................128

PlanningandDesignofDeepCohesiveTailingsDepositGuide............................................................................130

EffectsofShearingonDewateringandCompressibilityofTreatedTailings........................................................132

SoftSoilSettlementandStrengthasAppliedtoOilSandsFineTailings..............................................................135

MatureFineTailingsDrying(MFTD)Research.....................................................................................................137

DeepCohesiveDepositModelling........................................................................................................................139

EvaluationofVerticalStripDrainsinOilSandsTailings.......................................................................................141

DeepDepositModelling,AtmosphericFinesDryingTestCells............................................................................144

ConsolidationofFluidFineTailings......................................................................................................................147

SeepageInducedFlocculationTestingofMatureFineTailings............................................................................150

DeepDepositFilling,MonitoringandModelling..................................................................................................153

AcronymsandGlossary...........................................................................................................................157

COSIATAILINGSEPA–2018TAILINGSRESEARCHREPORT 1

TAILINGSCAPPING


SuppressionofFinesRe-suspensioninAqueousDepositionofTailingsCOSIAProjectNumber:TJ0088

ResearchProvider:StantecConsultingLtd.,BarrEngineeringandEnvironmentalScienceCanadaLtd.,BGCEngineeringInc.,andDeltares

IndustryChampion:TeckResourcesLimited

IndustryCollaborators:Imperial

Status:Complete

PROJECTSUMMARY

The purpose of the project is to understand the ability of various types ofmaterials that when placed on thetailings (i.e., tocapthetailings)preventor limit finesre-suspensionfordifferenttypesof tailings. Finesarethemineral solids with particle size equal to or less than 44 microns (μm) and do not include bitumen. Cappingmaterialsbeingconsideredincludeorganicmaterial(grass,shrubsandaquaticplants),sand,coke(aby-productofthe bitumen upgrading process), geofabrics, limestone, chemical amendments and polymers; while tailingsmaterialincludesaccelerateddewateringtailings(ADW),centrifugefinetailings(CFT),thickenedtailings(TT)withsand-to-finesratio(SFR)greaterthan1,andfluidtailingsat~30%solids(FT).Theprojectwillidentifythebodyofknowledgeonthreemitigationapproachestoreducefinesre-suspension.Theapproachesinclude:

• Chemicaltreatmenttoremovefinesfromtheoverlyingwatercapand/ortostrengthenthefinetailingstoreducefineserosion;

• Materialcappingtoisolatethetailingsfinesfromtheoverlyingwatercap;and• Establishmentofaquaticvegetationtoreducefineserosion.

Theobjectivesoftheprojectareto:

1. Identifymitigationmeasuresforthepreventionoffinetailingsre-suspensioninanaquaticenvironment;2. Capturethebodyofknowledgebyperformingaliteraturereviewofinformationavailableinthepublic

domain.Appropriatedatabasesandkeywords,conferenceproceedings,anddocumentsavailablethroughCOSIAwillbereviewed.Inaddition,experienceandexpertiseintheconsultingcommunitywillbeaccessed;and

3. Summarizetheresultsandidentifythebestoptionsforthenextphaseofworktofillknowledgegaps;namely,totestthepotentialmitigationmethods.


PROGRESSANDACHIEVEMENTS

Keyfindingsinclude:

Treatmentofthewatercaptoincreasesettlingvelocityofsuspendedfines

Favourableresultsinlabbeakersandcolumnswithpolymersandmetallicsaltswereencounteredbutunderverycontrolledandquiescentconditions. Someunfavourableresultssuchasincreasedeco-toxicityandwaterqualitydegradationwerefound.Theliteraturereviewedsuggestschemicaltreatmentwillremaineffectiveforfiveto10yearsoruntilcoveredbyothersediments.Tworelevantoilsandsstudieswerereviewed,includingaUniversityofAlbertaCO2labstudyonoilsandsprocessaffectedwater.TheclarityofthewaterdidnotimprovedespiteadropinpHfrom8to6.Alumdosingforturbidityremovalwasalsostudied.

Increasingtheerosionresistanceofthetailingsatthewatercap-tailingsinterface

Noinsitutreatmentstudieswerefoundforthinfinetailings(TFT)orfluidfinetailings(FFT).Insitutreatmentofcontaminatedsedimentswasperformedatfieldpilotandfullscaleinrivers,lakes,andharbours,including:

• Biological/chemical:additionofmicroorganismsand/orchemicalstothesedimentstoinitiateorenhancebioremediation;and

• Solidification/stabilization:additionofchemicalsorcementstoencapsulatethesediments.

Insitutreatmentischallengingfrombothanimplementationandeffectivenessstandpoint.Thisisduetolimitedprocess control, typically unfavourable environmental conditions, lower efficiencies compared to ex situtreatments,andthicksoftfoundationsthattypically,willnotsupportthickdenserlayers.

Createacap-isolatinglayerwithawatercapinplace

Sand capping has worked with substrate strengths greater than 25 pascals (Pa) (for FFT this would beapproximately35%solidscontent(SC)),usingverythin lifts. Theliteraturereviewedsuggeststhatoilsandsfinetailingscouldsupportasandcapinthe24to28%SCrange,butthatitwouldbeunstable.StabilitywouldincreasewithSCinexcessof30%andovertime(depositaging).

A sand raining fieldpilotdemonstrated theability todensifyMFTand forma cap ina careful, low loading rateapproach in a 4 metre (m) diameter casing filled with 3 m of FFT with a 2 m water cap. The study alsodemonstratedthatthesandcapcouldfail–potentiallyduetomechanismssuchasfingeringandsqueezing.

Developmentofaquaticvegetationtostabilizetailings/waterinterface

The study presents information using four tailings types grouped largely by geotechnical factors (i.e.,strength/consistency) and by fourwater conditions. These fourwater conditions include: unsaturated/crustedconditions (dry surface), drained but saturated conditions, shallowwater (0to less than 2m) and deep water(greaterthan2m).Asetofplantcommunitieswasdefinedforusebasedonspeciestoleranceforsubstrateandwater conditions. The vegetation community types were assigned to the water conditions and tailings typecategoriesbasedonthephysicalconditionsoftheseindividualcategories.Thephysicalconditions,soilstructure,access (for planting), and issues thatmay be encountered during vegetation establishment,within each of thewater conditions and tailings types, are also presented. Lists of candidate plant species (associated with the


communitytypes) thatmaybeused intestingduringsubsequentphasesof thestudyarepresentedforeachoffourtailingstypesandexpectedwaterdepths.

LESSONSLEARNED

1. Thereisalimitedbodyofknowledge(directlyrelevant)onthethreemitigationapproachestoreducefinesre-suspensioninanaquaticenvironment.

2. Oldertreatedtailings(TT,ADW,CFT)anddriedmaturefinetailings(dMFT)arelesslikelytoerodeandbecomere-suspendedthanFFTorrecentlydepositedtreatedtailings.Somemitigationmaybeneededinshallow,high-energyenvironments.

3. FFTandTFTlayersarelikelytobecomere-suspendedandrequiremitigation.4. Aquaticvegetationismostlikelytosucceedinshallowerwatercapdeposits.

RESEARCHTEAMANDCOLLABORATORS

Name InstitutionorCompanyDegree

orJobTitle

DegreeStartDate

(ForStudentsOnly)

ExpectedDegreeCompletionDateorYearCompleted

(ForStudentsOnly)

GordMcKenna BGCEngineeringInc. SeniorGeotechnicalEngineer

CarolJones Stantec SoilScientist,Principal

AlFandreyBarrEngineeringandEnvironmentalScienceCanadaLtd.

VicePresident,SeniorCivilEngineer

ToddDejournet

BarrEngineeringandEnvironmentalScienceCanadaLtd. SeniorEnvironmentalEngineer

KeithPilgrim

BarrEngineeringandEnvironmentalScienceCanadaLtd. SeniorWaterResourcesScientist

ArjanWijdeveld

BarrEngineeringandEnvironmentalScienceCanadaLtd./Deltares SeniorConsultantandResearcher

BenSheetsBarrEngineeringandEnvironmentalScienceCanadaLtd. SeniorGeologist

DirkLugerBarrEngineeringandEnvironmentalScienceCanadaLtd. SeniorGeotechnicalExpert


SurfaceStrengtheningofaSoftDepositCOSIAProjectNumber:TJ0090

ResearchProvider:BGCEngineeringInc.,NAITBorealInstituteofTechnology

IndustryChampion:CanadianNaturalResourcesLimited

Status:Year3of5

PROJECTSUMMARY

Canadian Natural Resources Limited (Canadian Natural) is evaluating the potential to sand cap soft, deep, finetailingsdepositsasapartofitsmineclosureefforts.Aspartofthisevaluationprocess,CanadianNaturaldesignedandconstructedthe30mwideby60mlongCentrifugeTestCellatJackpinemine(JPM) inthefallof2015andfilled itwith4.65mofcentrifugefluidfinetailings(CFFT) inJanuary2016. TheinitialsolidscontentoftheCFFTafterdepositionwasonaverage47%.

Since then, a series of field investigations have been carried out and various tailings strength improvementtechnologieshavebeen testedwith theoverall goal toplacea capon thedeposit. Strength improvementanddewatering technologies implemented include: vertical wick drains, the seeding and planting of native slenderwheatgrassseedandseedlingsandsandbarwillowseedlingsandcuttings,andthepumpingofpondedwaterfromthedepositsurface. Vegetationwas installedbothbyhandandbycustom-builtamphibiousrover. Wickdrainswere installedbycustom-builtArgoandbyamphibiousrover. Annuallysince2016, therelativeperformanceofstrength-improvingtechnologieshasbeencomparedwithanun-amended“control”zoneofthedeposit.

ThefollowingactivitieshavebeenconductedoverthelastthreeyearsattheCentrifugeTestCelltoevaluatethebenefitsofstrengthimprovementtechnologies:

• MonitoringofinstrumentationinstalledwithintheCFFT.Theinstrumentationincludes:vibratingwirepiezometersforporewaterpressure;sonicrangerandsettlementplatesfordepositthickness;totalpressurecellsforverticaltotalstress;thermistorsfortemperature;time-domainreflectometryprobesforvolumetricwatercontent;andsuctionsensorsformatricsoilsuction.

• CFFTsamplingandlaboratorytestingwerecarriedouttomeasureprofilesoftheCFFTsolidscontentandassesschangesovertime.

• InsituCFFTstrengthtesting,includingball/conepenetrationtesting,electronicvanesheartesting,andhandvanesheartesting,werecarriedouttomeasureprofilesoftheundrainedshearstrengthandassesschangeswithtime.

• Modifiedplatebearingtestswereconductedin2016and2017todeterminethebearingcapacityoftheCFFTsurfaceandevaluatethepotentialforsandcapping.


This research project advances the understanding of the multi-year effects of strength and dewateringimprovement technologies forCFFTata fieldscale,usingwickdrainsandvegetation,with theendgoalofsandcappingandterrestrialreclamation.


The following progress has been made since project inception to the end of 2017. Results from 2018investigationshavenotyetbeenassessed.

• Thedepositheighthasdecreasedbyapproximately20%ofitsoriginaldepositionthickness.• Solidscontentsatdepthhaveincreasedbyapproximately3%.• ThepeakundrainedshearstrengthoftheCFFTatdepthhasincreasedminimallysincedeposition,from

approximately1.5kPainAugust2016to2.5kPainSeptember2017.• Porepressuremeasurementsindicatethatlittletonoeffectivestressgainhasoccurred.• Adenser,stronger(approximately5kPa)crust,approximately40cmthick,hasformedatthetopofthe

CFFT,predominantlyduetofreeze-thawconsolidation,evaporationandperiodicsurfacewaterremoval.• High,undrainedshearstrengthvaluesinthedepositcrustareobtainedwhenitisunsaturated,butthese

strengthgainsarequicklylostwhenrewetted.• Sixmonthsafterwickdraininstallationthebenefitsondepositdewateringandstrengthgainare

negligible.Comparedtotheun-amendedcontrolsection,theCFFTsurfaceis5cmlower,theCFFTstrengthissimilar,andthesolidscontentis1%higher.

• Wherethecrustremainedunsaturatedonthesideslopesofthedeposit,thepeakundrainedshearstrengthinareaswithhighvegetationcoverrangedfrom20to80kPainthetop30cm,versusvaluesof10to50kPaintheun-amendedcontrolzone.However,duetocellconfiguration,vegetationsurvivorshipwaslowinfloodedareasleadingtolessstrengthgaininthecentral(thickest)portionofthedeposit,highlightingtheimportanceofsurfacewaterremovalforuplandplantspeciessurvivorship,strengthgainanddrying.

LESSONSLEARNED

Thefollowingemerging lessonsareofsignificancetotheoilsands industry,withtheendgoalofreclaimingsofttailingsdeposits:

• Wickdrainscanbeefficientlyinstalledfromacustom-builtArgoworkinginfrozenconditions.Overashortsix-monthperiod,wickdrainsdonotappeartoappreciablyenhanceCFFTdewateringandstrengthening.

• Nativevegetation(sandbarwillowandslenderwheatgrass)canbesuccessfullyplantedandgrownwithinCFFTusingavarietyofmethodssuchasseed,seedlings,andcuttings.

• NativevegetationcanleadtoanincreaseinCFFTstrengthinthetop30cmoveronegrowingseason.• Overaperiodoftwoyearssincedeposition,strengthamendmenttechnologieshavenotsignificantly

enhancedstrengthgainordewatering.Thedepositisnotyetstrongenoughtosupportanoperationallyfeasiblesandcappingtrial.


• Thedepositwillcontinuetobemonitoredandinvestigatedtoassesstherelativeperformanceoftheinstalledstrengthamendments(wickdrainsandvegetation)overanextendedtimeperiod.

PRESENTATIONSANDPUBLICATIONS

ConferencePresentations/Posters

Smith,W., Olauson, E., Seto, J., Schoonmaker, A., Nik, R.M., Freeman, G.,McKenna, G. 2018. In Preparation.Evaluation of Strength Enhancement and Dewatering Technologies for a Soft Oil Sands Tailings Deposit. SixthInternationalOilSandsTailingsConference2018,Edmonton,Alberta,December9-12,2018.


Institution:CanadianNaturalResourcesLimited

PrincipalInvestigator:BGCEngineeringInc.


orJobTitle

DegreeStartDate

(ForStudentsOnly)


(ForStudentsOnly)

MrudulaParanjapeCanadianNaturalResourcesLimited

TechnologyDevelopmentEngineer

ErinOlauson BGCEngineeringInc.SeniorGeotechnicalEngineer

WillSmith BGCEngineeringInc.GeotechnicalEngineer-in-Training

JackSeto BGCEngineeringInc.PrincipalGeotechnicalEngineer

GordMcKenna,PhDMcKennaGeotechnicalInc.

GeotechnicalEngineer,LandformDesigner

AmandaSchoonmaker,PhD

NAITBorealResearchInstitute

NSERCIndustrialResearchChairforCollegesinBorealReclamationandReforestation

JasonSong,PhD O’KaneConsultantsInc. SeniorGeoscientist


LiteratureReviewforIn-line/On-lineRheologyMonitoringTechnologyCOSIAProjectNumber:TJ0092

ResearchProvider:SaskatchewanResearchCouncil


Status:Complete

PROJECTSUMMARY

Rheological properties (flow characteristics) are useful indicators of the degree of aggregation or dispersion ofparticles within slurries. Typical rheological parameters (such as viscosity and yield stress) represent differentcontributions toward overall slurry behaviour, and can be used to establish criteria for physical stability of theslurryandtocontroliftheslurrypropertydepartsfromthedesiredflowbehaviour.

Despitetheimportanceofrheologicalproperties,yieldstressandviscositydataarerarelyleveragedtocontrolandadjustmineralslurryprocesses.Thisisduetodifficultiesinmeasuringtheseparametersinrealtime.Currently,most rheology tests are conducted at-line or off-line, resulting in a time delay before data are available. It isdifficulttouserheologicaldataascontrolparameterswhenrheologicalresultsareobtainedhoursordaysafterasampleistaken.

Inaneffort tobetterunderstand thepotentialbenefitsofusing rheologicaldataascontrolparametersand thedifficultiesassociatedwiththisendeavour,TeckResourcesLimited(Teck)contractedtheSaskatchewanResearchCouncil (SRC) to conduct a literature review to explore the current state of in-line/on-line rheologymonitoringtechnology.

Thereviewdiscussesthebackgroundandmotivationsforslurryrheologymeasurementalongwiththechallengesfacingrheologymeasurementforclaybasedslurries.Basicrheologicalconcepts,modelsandpipeflowequationsthatcouldbeusedintherheologymeasurementarepresentedalongwithgeneralprocessmeasurementmethodsandessential featuresrequiredfor in-line/on-linemeasurement. Thecurrentdevelopmentsandresearchon in-line/on-line rheologymeasurement technology and commercially available in-line/on-line viscometers identifiedfrom literature are summarized, followed by a summary of conclusions and comments relating to futuredevelopmentofrheologymonitors.

LESSONSLEARNED

Thefollowingsummarizestheauthor’sobservationsfromthisstudy:

1. Rheological properties are useful indicators of the degree of aggregation and dispersion of particleswithinslurries. Rheologicalparameters(i.e.,viscosityandyieldstress)representdifferentcontributionstowardoverallslurrybehaviour,andcanbeusedtoestablishcriteriaforphysicalstabilityoftheslurryand


tocontrol if theslurrypropertydepartsfromthedesiredflowbehaviour. Therefore,rheologicalvaluescouldbeusedas controllingparameters for feed forwardor feedbackcontrol systems if in-line/on-linerheologymonitoringsystemswereavailable;

2. For Newtonian and non-Newtonian homogeneous fluids (e.g., oil and flocculant solutions), rotationalviscometrycanbeusedas in-line/on-lineandat-line/off-linerheologymeasurementdevices;concentriccylinder rotationalviscometrycanalsomeasure therheologyofhomogeneousandnon-settlingslurries(e.g.,wellmixedfluidfinetailings(FFT)andmaturefinetailings(MFT))ifsolidparticlesintheslurrywouldnotsettleandjamthemeasuringcomponentsduringmeasurement;avertical,flowthroughdesignmaypreventslurrysettlinginthemeasuringcupbuthaveothercomplicatingfactorsduetoturbulentflow;

3. Therearecommercialin-line/on-lineviscometersavailablewhicharecapableofmeasuringtherheologyforhomogeneous fluidsandnon-settling slurries, andgenerating real-timeviscosityandapparent yieldstressdata;

4. Pipeflowviscometrycanbeusedtomeasuretherheologyofhomogeneous,heterogeneousandsettlingslurries,providedthesolidsparticleswouldnotsettleduringthemeasurement.Apipeflowviscometerisusuallyoperatedinat-lineoroff-linesetupundercontrolledoperationtoavoidparticlesettlingbutcouldpotentiallybeadaptedforon-linemeasurement;

5. Tomeasure the rheologyof a non-Newtonian, heterogeneous and settling slurry (e.g., oil sand tailingswithcoarseparticles)inanin-lineoron-linebasis,itmustmeetthreecriteria:

a) keeptheslurryfullysuspendedduringmeasurement;b) operatecontinuouslyandgeneratedatainreal-time;andc) generateaflowcurvewithmultipledatapointssorheologycanbedetermined.

Therearetwocommerciallyavailableon-linerheometersthathavepotentialtomeetallthreecriteriaatthesametime,ifeitherofthemcanovercomethecomplicationscausedbysettlingslurries;and

6. Severalin-line/on-linerheologymeasurementmethodshavebeendiscussedinthisreview.Basedontheprocess requirementof theapplication, someof themethodshavepotential tobedevelopedasan in-line/on-linerheologymeasuringdevice.

LITERATURECITED

Thisliteraturereviewgatheredinformationfrom77publications.


Institution:SaskatchewanResearchCouncil

PrincipalInvestigator:RuijunSun,M.Sc.,MBA,P.Eng.,SeniorResearchEngineer


TAILINGSTREATMENTTECHNOLOGIES


FinesMeasurementWorkingGroupCOSIAProjectNumber:TE0017andTW0010

ResearchProvider:FinesMeasurementWorkingGroup


IndustryCollaborators:Imperial,SuncorEnergyInc.,SyncrudeCanadaLtd.,TeckResourcesLimited

Status:Completed

PROJECTSUMMARY

The COSIA Tailings Environmental Priority Area (EPA) and its FinesMeasurementWorking Group (FMWG)wastaskedwithdevelopingastandardizedmethodforreportingpercent(%)finesat44micronforsamplesrangingfromoilsandscorestofluidtailings,withincidentalbenefittomeasuringtheentireparticlesizedistribution(PSD).

TheCOSIATailingsEPAapprovedtheproject,“FinesMeasurementMethodologyforDirective74”onApril3,2013,withthefollowingobjective:

“Theoverarchingobjectiveistodevelopamethodologywhichgivestechnicallyandstatisticallydefendable,consistentmeasurementmethodologyforoilsandsfines(<44micronparticlesize)whichisapplicableacrossallareasofanoilsandsprocessingfacility.Themeasurementmethodmustbeconsistentwiththeobjectiveof producing a full fines balance across the facility and its operating processes. Therefore, the selectedmeasurement protocol must be viable for measuring materials such as ore, slurry, rejects, beach finescaptureandfluidfinetailings(FFT)inordertocloseamaterialbalance.

This effort will result in the identification, development and industry-wide adoption of a standardmeasurementmethodologyforfines(<44microns).”

The FMWG carried out a Design of Experiment (DOE) study primarily to understand the effect of samplepreparationvariablesonthereportedfinescontent.ThisledtothewritingofadraftUnifiedFinesMethods.Asaresultofapilotinter-laboratorystudy(ILS)andaformalstudyknownasILS1,theFMWGrevisedtheUnifiedFinesMethod (Method) on several occasions. ILS 2 was intended to provide the repeatability and reproducibilitystatistics for the final Method. A decision about accepting this method for the purposes stated earlier waswithheldwiththerescindingofDirective074:TailingsPerformanceCriteriaandRequirementsforOilSandsMiningSchemes(D074)(rescindedbyDirective085:FluidTailingsManagementforOilSandsMiningProjectsin2016andupdatedin2017).

As the work by the FMWG draws to a close the following recommendations are being made regardingcommunicationofthefinalmaterialsandfindingsbytheFMWG.


Methodforfinesdeterminationforlessthan44microns,FMWG

GiventheresultsoftheILS,theFMWGacknowledgedthattheMethodinitscurrentformdidnotmeetitsoriginalobjective. WithD074 rescinded and theperceived amount ofworkneeded tomeet theoriginal objective, theFMWGhas recommended to theTailingsEPASteeringCommittee (SC) thatno furtherupdatesbemade to theMethodoffinesdeterminationforlessthan44microns.

A commitment to share the ILS report with the labs participating in the ILS was made. Given the broadparticipationintheILSbylocallabssupportingtheindustry,thereleaseoftheILSreporttotheselabsconstitutesaformof limitedpublic release. Bothversionsof theMethodusedduring the ILSareattachmentswithin the ILSReport,2016,meaningthatiftheILSReportismorefullyreleasedtothepublicdomainviatheCOSIAwebsite(asrecommended below), the supporting documents would be available to readers of the report. Therefore, theFMWG has recommended to the SC that the finesmeasurementmethod as part of the ILS report supportingdocumentationbereleasedthroughtheCOSIAwebsite.

MethodforDeanStark

Although Dean Stark is a common practice across the industry, an actual formalmethod that is owned by anorganization was discovered to be unavailable during the creation of the fines measurement method, as theprevious owner, ACOSA, has disbanded. The Dean Stark method as described in the ILS report supportingdocumentation would also become available online, which would be an additional benefit of releasing the ILSreportthroughtheCOSIAwebsite.


DesignofExperimentReport,2015,byNARCOSS

In2014theNorthernAlberta InstituteofTechnology(NAIT)AppliedResearchCentreforOilSandsSustainability(NARCOSS)produceda conferencepaper for the InternationalOil Sands TechnologyConference (IOSTC)on theDesignofExperiment(DOE)ofamethodforthemeasurementof<44micronfines. Atthattimethereportwasnotcompletesoashortersummarywasreleasedthroughtheconferenceproceedings.

GiventheDOEispartiallyinthepublicdomainalreadyitisrecommendedbytheFMWGthatthecompletedDOEReport, 2015, be supported for release through the reports area of the COSIA website. The communicationsassessmentprocesswouldbeusedtoverifythatreleaseisintheinterestoftheCOSIAmembercompanies.

Inter-LaboratoryStudy(ILS)Report,2016,byInnoTechAlberta

From 2014 through to 2016 InnoTech Alberta (InnoTech) facilitated the Inter-Laboratory Study following ASTMguidelinestoproducearepeatabilityandreproducibilitystatementforthemethoddesignedbyFMWG.TheworkiscompleteandhasbeenendorsedbytheFMWG.

FMWG recommends that the ILS report (including attached finesmeasurement andDean Starkmethods in theappendix)withaccompanyingmemoaboutconcernsbepostedontheCOSIAwebsite.

ThememoattachedtotheILSreportshouldmakeitclearthatthemethodisnotanindustrystandard.


Finesmethodvariabilitypaper(s),2017

NARCOSSwas retainedagain after the completionof the ILSReport todo further analysisof theeffectsof theproceduresbasedonthedataretainedduringtheILS.ThisfurtheranalysiswaspresentedattheFMWGworkshopinAprilof2017.However,nofurtherworkhasbeenpursuedandnopapershavebeenproduced.Therefore,theFMWGhasnorecommendationsrelatedtothisstudyatthistime.

NextSteps

In the event that the Alberta Energy Regulator requests amethod for themeasurement of fines that are <44microntheFMWGbelieves that furtherworkwouldneedtobecompletedtoproduceauniversally satisfactorymethod.

LESSONSLEARNED

Although the FMWG did not agree upon a new method the DOE and ILS revealed and confirmed numerousfindings about fines measurement. These findings will allow the operators to improve their own in-housemethodologies.


Canada’sOilSandsInnovationAlliance(COSIA)FinesMeasurementWorkingGroup(FMWG).2016.UnifiedFinesMethodforMinus44MicronMaterialandforParticleSizeDistribution.(http://cosia.ca/uploads/documents/id18/COSIA%20FMWG%20Fines%20Method%20February%202016.pdf).

NorthernAlbertaInstituteofTechnology(NAIT)AppliedResearchCentreforOilSandsSustainability(NARCOSS).2014.COSIADesignofExperimentStudyinSupportofDevelopmentofaStandardforFinesMeasurementinOilSands.https://sites.google.com/a/ualberta.ca/iostc2014/.


PrincipalInvestigator:COSIAFinesMeasurementWorkingGroup

ResearchCollaborators:AlbertaEnergyRegulator,NorthernAlbertaInstituteofTechnologyAppliedResearchCentreforOilSandsSustainability,InnoTechAlberta


Long-termDewateringofAmendedOilSandsTailingsCOSIAProjectNumber:TE0006andTE0036

ResearchProvider:CarletonUniversity


IndustryCollaborators:CanadianNaturalResourcesLimited,Imperial,SuncorEnergyInc.,SyncrudeCanadaLtd.

Status:Year2of4

PROJECTSUMMARY

Theprojectaimstoreducedewateringperformanceuncertaintyinoilsandstailingsdepositsthrough:

• Increasingreliabilityofpredictionsoflong-termsettlementanddewatering;and• Improvingunderstandingofhowpipelinetransportmodifiessubsequentdewateringbehaviour.

Thespecificobjectivesanddeliverablestoachievethesegoalsinclude:

a) Improvingmethodsandexperimentaltechniquestorapidlyestimateconsolidationproperties,namelythecompressibilityandhydraulicconductivityfunctions;

b) Investigatingtime-dependentbehavioursinpolymer-amendedfluidfinetailings(FFT)(creepandthixotropy/structuration)thatpotentiallyinfluencelong-termconsolidationpredictions;

c) Incorporatingsuchbehavioursintoourresearchgroup’sconsolidation-desiccationmodelUNSATCON;d) ExtendingUNSATCONfromaonedimensional(1D)totwodimensional(2D)model;e) Evaluatinglong-termdewateringpotentialforarangeofpolymertypes,andprovidingfeedbackto

polymerdevelopersonhowtooptimizepolymersforlong-termtailingsdewatering;andf) Studyingchangesinpipelinerheologyandlinkingtopost-pipedewateringbehaviourtooptimizepolymer

dosageandtoassistingoperatorsdevelopimprovedtechnologiesforon-specandoff-specdetection.


Wehavefoundthatstructuration/agingisanimportantphenomenoninatleastsomekindsofpolymer-amendedFFT.Structurationmeansthecompressibilityofthematerialdecreases(thematerialstiffnessincreases)overtime,independentofdensity.Theconsequenceisthatcurrentpredictionsoflong-termdewateringindeepdepositsoftailingsmayover-predict long-termdewatering if compressibilitymeasuredover a shortduration isused in thepredictions–whichitusuallyis.Specifically,structurationgeneratedpre-consolidationpressuresover50kPaoveraperiodof100daysin10cmthicksubmergedsamplesofFFTmixedwithstandardanionichighmolecularweightpolymers,usingmixingproceduresdesignedtosimulateshortpipelinetransport,suchastheAtmosphericFinesDrying (AFD) technology. Structuration did not appear to progress beyond 100 days. We developed three


candidate methods to rapidly estimate the hydraulic conductivity-void ratio relationship. These methods aredescribed inanumberofpapers, includingapaperpresentedat the InternationalOilSandsTailingsConference(IOSTC) 2018. Thesemethods range in time and cost from single pointmeasurement of hydraulic conductivitycoupledwithdatabase learning, tocolumntests involvingexsitumeasurementofdensityusingnon-gammaraytechniques.Thesetechniquesaresufficienttobeusedasscreeningtoolstoevaluateproposedchangestocurrenttechnologies,suchasnewpolymers.

Wefoundthathigh-poweredopticalmicroscopycoupledwithdigitalimageanalysisisapowerfultoolforstudyingflocevolutionduring short-termdewatering (two to threedays)or for studying theeffectsof shearingand flocrecovery during pipeline transportation and deposition. Flocs are clumps of fine particulates formed duringflocculation.WedemonstratedthatincertaintypesofflocculatedFFT,flocscontinuetogrowoveratleasta48-hourperiod.Flocsinitiallyapproachingmaximumdiametersof200micronsarereducedbyshearing,butrecoverthroughagingtoflocsupto60micronsindiameter.

For thework linking pipeline transport to dewateringwe replicated earlierwork preformed in industry using alarge coquette rheometer to simulatepipeline transport. Wearenowprogressing tounderstandhowmaterialchangesandrecoversaftershearingduringpipelinetransport,usingopticalmicroscopyandadvancedrheometry.We plan to generate tailings exposed to different flow regimes and test them in our specialized columnexperimenttomeasureconsolidationproperties.

Three creep models went into our UNSATCON model for simulating consolidation and desiccation of tailingsdeposits.Weareimplementingastructurationcomponenttothesemodels.

LESSONSLEARNED

Thechangeinthecompressibilitycurveduetostructurationpotentiallyhasgreatsignificancetotheanticipatedrateofsettlementandstrengthgain indeepdeposits. Ifstructurationoccurs infielddeposits,thentheratesofsettlement and strength gain in the long-term may be less than currently anticipated. We are working onexamining the generality of our results, in otherwordswhat type of tailings depositswould be subject to thisbehaviour.Additionally,wewillworkwithCOSIAmembercompaniestoexaminetheirpilotsandfieldtrialstoseeifcreepandstructurationarenetpositivesornegativestotheperformanceoftheirdeposits.Ifnegative,therearewaysofdepositingtailingsthatwouldminimizethenegativeaspectsofstructuration,andwecanassistmembercompanieswiththosedecisions.

Themethodswe proposed at our student-interaction day and in conference papers (Babaoglu et al. 2018 andBabaogluandSimms2018,2017)torapidlyestimatetheconsolidationpropertiesaresufficientlyaccuratetobeused at least as screening tools. Industry can adopt thesemethods as tests for key performance indicators, ifconvenient.Specificlessonsorfindingsdeterminedfromthesetestsinclude:

• usingasinglemeasuredvalueofhydraulicconductivityathighvoidratiosubstantiallyimprovestheaccuracyofmethodstoestimatethecompletehydraulicconductivityfunctionthatuseAtterberglimits;

• thecompressibilityfunctionitselfcanbeusedasapredictorforthehydraulicconductivityfunction;and• theinstantaneousprofilemethodusedinsoilsciencetoestimatehydraulicconductivityfrominsitudata

canbeadoptedforslurrieswithhighvolumechangesuchasFFT.



Theses

Khattack,MuhammadHissan.2018.MicrostructuralQuantitativeAnalysisofPolymerAmendedFluidFineTailingsUsingDigitalImageProcessingTechinques.M.A.Sc.Thesis.

Qi, S. 2017.Numerical Investigation for Slope Stability of Expansive Soils and Large Strain Consolidationof SoftSoils.Ph.D.thesis

JournalPublications

Qi,S., Simms,P.Vanapalli, S.2018.Discussionof “Fromsaturated tounsaturatedconditionsandviceversa”byMartíLloret-Cabot,SimonJ.Wheeler,JubertA.Pineda,EnriqueRomero,andDaichaoSheng. ActaGeotechnica,13:489.https://doi.org/10.1007/s11440-017-0625-2.

Qi,S.,Simms,P.,Vanapalli,S.,Daliri,F.2018.Couplingelasto-plasticbehaviourofunsaturatedsoilswithpiecewiselinearlargestrainconsolidation.SubmittedtoGeotechnique.

Qi,S,Simms,P.2019.Robustmethodstoestimateconsolidationpropertiesfromcolumnexperiments.SubmitedtoCanadianGeotechnicalJournal.


Babaoglu,Y.,Qi,S.,Simms,P.2018.RapidEstimationofHydraulicConductivityforFluidFineTailings.ProceedingsofSixthInternationalOilSandsTailingsConference2018.December9-12,2018.Edmonton,Alberta.

Babaoglu,Y.,Simms,P.2018.EstimatingHydraulicConductivityfromCompressibilityCurvesforFluidFineTailings.GeoEdmonton,71stCanadianGeotechnicalConference,Edmonton,Alberta,September23-26,2018.

Baboaglu, Y., Simms, P. 2017. EstimatingHydraulic Conductivity fromSimpleCorrelations for FineGrained SoilsandTailings.InProceedingsofGeoOttawa2017,CanadianGeotechnicalConference,October2-4,2017,Ottawa,Ontario.Electronicproceedings.

Hurtado, O. Simms, P. 2017. Desiccation in mesoscale deposition experiments on centrifuge cake tailings. InProceedings of GeoOttawa 2017, Canadian Geotechnical Conference, October 2-4, 2017, Ottawa, Ontario.Electronicproceedings.

Kazemi, K., Simms, P. 2017. Post-failure runout analysis from tailings dams using viscosity bifurcation rheology.ProceedingsofTailingsandMineWaste2017,November5-8,2017,Banff,Alberta.

Khattak, M.H., Simms, P. 2018. Image Processing For Quantitative Analysis Of Fluid Fine Tailing’s, DosedWithAnionicPolyamideBasedFlocculant. GeoEdmonton,71stCanadianGeotechnicalConference,September23 -26,2018,Edmonton,Alberta.

Qi, S, Thomas,W., Simms, P, andHmidi,N. 2017.Hydro-geotechnical analysis of a thickened tailingsdeposit inNorthernCanada.ProceedingsofTailingsandMineWaste2017,November5-8,2017.Banff,Alberta.


Qi,S.,Simms,P.2018.Analysisofdewateringanddesaturationofgenericfielddepositionscenariosforthickenedtailings.AcceptedtoPaste2018,InternationalSeminaronPasteandThickenedTailings,Perth,Australia,April10-122018.

Qi, S. Simms, P. 2018. Hydro-mechanical coupling in dewatering simulations for mine tailings management.UNSAT2018,InternationalConferenceonUnsaturatedSoils,HongKong,August4-8,2018.

Qi,S.,Salam,M,Simms,P.2018.CreepandStructuration inTailingsand inNaturalClays.Proceedingsof IOSTC2018.

Qi,S.,Salam,M.Simms,P.2017.Modellingthixotropy inpolymeramendedoilsandstailings. InProceedingsofGeoOttawa2017,CanadianGeotechnicalConference,Oct2-4,2017,Ottawa,Canada.Electronicproceedings.

Salam, A., M., Simms, P., Ormeci, B. 2018. Structuration in Polymer Amended Oil Sands Fine Tailings.GeoEdmonton,71stCanadianGeotechnicalConference,Edmonton,Alberta,September23-26,2018.

Salam, A.M., Simms, P., Ormeci, B. 2018. Evidence Of Creep & Structuration In Polymer Amended Oil SandsTailings.ProceedingsofIOSTC2018.

Salam, M, Simms, P. Ormeci, B. 2017. Thixotropy and dewatering in polymer amended oil sands tailings InProceedings of GeoOttawa 2017, Canadian Geotechnical Conference, October 2-4, 2017, Ottawa, Canada.Electronicproceedings.

Simms, P., Qi, S. 2018. Pore-size distributions measured by mercury intrusion porosimetry:implications forfunctionalrelationships inhydromechanicalmodels.UNSAT2018, InternationalConferenceonUnsaturatedSoils,HongKong,August4-8,2018.



Institution:CarletonUniversity

PrincipalInvestigator:PaulSimms


orJobTitle

DegreeStartDate

(ForStudentsOnly)


(ForStudentsOnly)

NickBeier UniversityofAlberta AssistantProfessor

JoaoSoares UniversityofAlberta Professor

SunchaoQi CarletonUniversity/SichuanUniversityChina

PostdoctoralFellow/ProfessoratSichuan 2017 CompletedPostDoc

December2018AbdulghaderAdulrahmna CarletonUniversity ResearchEngineer/PhD 2017 2020YagmurBaoaboglu CarletonUniversity PhDCandidate 2016 2020

MuhammadAsifSalam CarletonUniversity PhDCandidate 2015 2019

NargesGheisari CarletonUniversity PhDCandidate 2018 2022HadiFateh CarletonUniversity PhDCandidate 2019 2023

OswaldoHurtado CarletonUniversity MScCandidate 2016 2018

DavidIgnaebion CarletonUniversity MScCandidate 2018 2020

HissanKhattack CarletonUniversity MScCandidate 2017 2018

HirlatuPeruga CarletonUniversity MScCandidate 2018 2020

LindaBotha UniversityofAlberta PostdoctoralFellow 2017 2017SarangGumfekar UniversityofAlberta PhDCandidate 2018 2021

VahidVajinejad UniversityofAlberta PostdoctoralFellow 2017 2019

YunhaiZhang UniversityofAlberta PhDCandidate 2019 2023

KwakuAmoako UniversityofAlberta M.A.Sc.Candidate 2018 2020


MicrobiologicalandVegetationforTailingsManagement(BugsandVeggies)COSIAProjectNumber:TE0039

ResearchProvider:NorthernAlbertaInstituteofTechnology

IndustryChampion:CanadianNaturalResourcesLimited(CanadianNatural)


Status:Year2of2

PROJECTSUMMARY

EarlyresearchbySilva(1999)examinedplantsasadewateringtechnologyforoilsandstailingswastesandfoundseveral species of grasses were successful in this application at small scale. However, oil sands tailings aredeficientinsoilnutrientsrequiredbyplantstogrowandwouldthereforerequiresubstantialquantitiesoffertilizertobeadoptedasadewateringtechnologyatscale. It iswellknownthatmanyplantsdependonnitrogenfixingbacteria in their roots and soil tomeet nutrient requirements; however, commercially available nitrogen fixingspeciesarechallengedbythehighsalinity,hydrocarboncontent,andanoxicconditionsthatarecharacteristicofoilsandstailings.AstudybyCollinsetal.(2016)foundlownumbersofnitrogenfixingbacteriawerepresentinoilsandstailingsandcouldbeenrichedtoproduceenoughbioavailablenitrogentosupportacommunityoforganicaciddegradingbacteria.Bycombiningthesetwoconceptsatalargerscaleusingnativeborealplantspeciesinanoutdoorenvironment,wesoughttodemonstratetheplausibilityofplant-mediatedtailingsdewateringatscale.

Thegoalofthisprojectistodemonstratetheintegrateduseofnativeborealplantspeciesandindigenousselectedbacteriaculturescapableofdegradingresidualhydrocarbonsandorganicacids,whilefixingnitrogeninthesoilastoolstofurtheracceleratethetransformationofmaturefinetailings(MFT)intoareclaimedsoil.Thesenitrogen-fixingbacteriahavethepotentialtoincreasetheplant-availablenitrogenintailingsandacceleratethegrowthofnative boreal plant species. These plants will in-turn dewater the tailings through evapotranspiration therebyincreasingshearstrengthofthematerialsfordeposition.

The current work is the first to attempt growing native boreal plant species supplemented with indigenoushydrocarbondegrading,nitrogenfixingbacteriaonoilsandstailings.Previouslypublishedgreenhousestudiesdidnotcontainbacterialinoculumoramendments,weresmallscale,andconductedindoors.Plantgrowth,nutrientrequirements,andsurfaceevaporationcanallbeaffectedbypotsizeanddepthaswellasenvironmentalfactorsnotreplicableinagreenhouse.Inadditiontobacterialinoculumtomeetnutrientrequirementsandamendmentstopromotebacterialgrowth,the“greenhouse”studywasconductedin7.8litre(L),1mcolumnsoutdoorsmakingthisstudymoresimilartofieldconditionsthanotherstudies.Thedatacollectedfromthisstudywillbetterinformour understanding of the synergistic benefits of using nitrogen fixing bacteria, amendments, and native borealplantspeciestodewatertailingsonalargerscaleunderenvironmentalconditions.Ifoneormoretreatmentsarefound to substantially increase the shear strength of tailings, this biotechnology can be scaled-up for fieldapplicationatapilotsite.



Phase1workhasbeencompleted: DuringPhase1,executedbetweenSeptember2017andFebruary2018,weevaluated severalbiocompatible solidparticlesas carriers forbacterial cultures isolated fromwell-characterizedanoxicMFT and enriched to degrade specific organic compounds and fix N2 to ammonium. We evaluated thefollowingmaterialsassubstrates:

• engineeredmicroporoussilicamaterial;• activatedcarbon;• diatomaceousearth(DE);and• biomass-derivedflyash.

Weinvestigatedmicroorganismsenrichedfromthefollowingtailingssources:

• CanadianNaturalMuskegRiverExternalTailingsFacilityMFT;• SyncrudeCanadaLtd.MildredLakeSettlingBasinMFT;and• twoin-houseenrichmentsusingthickenedtailingsandtailingscentrifugecakeprovidedbyImperialand

CanadianNatural,respectively.

We evaluated substrate cultures by measuring methane production, hydrocarbon degradation, and acetylenereductionasanindicatorofnitrogen-fixation. Inthesetrials,culturesgrownonDEproducedthemostmethanewithSyncrudeCanadaLtd.andCanadianNatural’senrichmentsproducingsignificantlymoremethanethantailingscakeorthickenedtailingscultures.Hydrocarbondegradationresultsareconsideredinconclusiveduetochangesin surface chemistry from microbial growth across different substrates. Canadian Natural Resources LimitedculturesgrownonDEwere found tohave thehighestacetylene reducingactivity,withnosignificantdifferencebetweenothercultures.Basedonmethaneandacetylenereductionresults,CanadianNaturalResourcesLimitedenrichmentonDEhadthehighestmetabolicandnitrogenfixingactivityascomparedtootherculture-substratecombinationsexaminedinthisstudy.ThiscultureandsubstratecombinationwasselectedforscaleupforPhase2.Methanemonitoringandhydrocarbonanalysesinthescaledupculturesarecurrentlyunderwaywithacetylenereductionassayinprogress.

ThemostactiveculturewiththehighestlevelofmicrobialgrowthwasscaledupduringtheperiodbetweenMarch2018 and May 2018. One conference proceeding focusing on Phase 1 was submitted and accepted for theInternationalOilSandsConference(IOSTC)inDecember2018.

Phase 2 work is nearing completion: During Phase 2, slender wheatgrass (Elymus trachycaulus) and sandbarwillow(Salixinterior)weregrownoncentrifugecakeandthickenedtailingsinoculatedwiththescaledupbacterialcultures aswell asotherorganic amendments (hydrochar andpeat) from thebeginningof June2018and thendestructivelyharvested inSeptember2018. Aboveandbelowgroundbiomassdata, solidscontent,andtailingsstrength are under evaluation. Results are still being compiled; however, current data suggest significantdifferencesinplantgrowthandtailingsstrengthbetweentreatments.AfinalreportandmanuscriptdetailingthefindingswillbepreparedinMarch2019.


LESSONSLEARNED

• Diatomaceousearthpromotestherapiddevelopmentofoilsandsmicrobialcommunitiesundernitrogen-limited conditions. Usingmethane production as a proxy, cultures grown on DEmetabolized organicsubstrates 10 times faster than other substrates or nutrient media alone. Diatomaceous earth alsopromptedthehighestrateofnitrogenfixation(asdemonstratedusinganacetylenereductionassay)outofthesubstratesexamined.

• CanadianNaturalandSyncrudeCanadaLtd.enrichmentcultureshadsignificantlyhighermetabolismthanothercultureinoculum(235µmoland188µmolmethane(CH4)),respectivelyascomparedto~20µmolCH4 in thickened tailings and tailings cake tailings cultures). Canadian Natural cultures also had thehighestmeanaverageofnitrogen fixingactivityat12µmolethyleneafter19days incubation,whileallother cultures produced less than 9 µmol ethylene (N2 proxy). However the differences were notsignificant. Oneenrichment andone tailings culture, CanadianNatural and thickened tailings cultures,wereselectedforevaluationinthescale-upphase.

• During the scale-up phase, CanadianNatural cultures degraded toluene tomethane significantlymoreeffectively than thickened tailings and sterile cultures. By day 41, ≤ 2 µmol CH4 were detected inthickenedtailingsandsterilecontrolcultureswhereas123µmolCH4wasproduced inCanadianNaturalenrichmentcultures.CanadianNaturalculturesalsodegraded7mgtoluenebyday42ascomparedto4mgtolueneinthickenedtailingscultures.Nosignificantdecreasewasobservedinthesterilecontrols.

• Data are still being compiled from the outdoor growing trial phase; however, dewatering rates wereroughlydoubledintailingscolumnswithplantsascomparedtocolumnswithoutplants.

• Thereisadirectcorrelationbetweenplantgrowthandshearstrength.

• Severalamendments includingbacteria+organicamendment(hydrochar)showedasignificant increaseinshearstrengthascomparedtountreatedplantsontailings.

LITERATURECITED

Collins, C.E.V., J.M. Foght, and T. Siddique. 2016. Co-occurrenceofmethanogenesis andN2 fixation in oil sandstailings.Sci.TotalEnviron.565,306–312.

Silva,M.J.1999.Plantdewateringandstrengtheningofminewastetailings.PhDthesis,UniversityofAlberta.


Collins,V.,A.Schoonmaker,H.Kaminsky,A.Sedgwick,C.Chigbo,andP.Mussone.2018.DevelopmentofBacterialInoculumforthePromotionofPlantGrowthonTailingsMaterial.InternationalOilSandsTailingsConference2018,Edmonton,Alberta.AcceptedOctober2018.



Institution:NorthernAlbertaInstituteofTechnology

PrincipalInvestigators:Dr.PaoloMussone,Dr.AmandaSchoonmakerandAndreaSedgwick


orJobTitle

DegreeStartDate

(ForStudentsOnly)


(ForStudentsOnly)

VictoriaCollinsNorthernAlbertaInstituteofTechnology ResearchAssociate

Dr.HeatherKaminskyNorthernAlbertaInstituteofTechnology ResearchAssociate

Dr.ChibuikeChigboNorthernAlbertaInstituteofTechnology ResearchAssociate

KaelaWalton-SatherNorthernAlbertaInstituteofTechnology

Studentresearchassistant/DiplomainBiologicalSciencesRenewableresources

Sept2016 June2018

CarlZhangNorthernAlbertaInstituteofTechnology

Studentresearchassistant/DiplomainCivilEngineeringTechnology

Sept2017 June2019

TaimurQureshiNorthernAlbertaInstituteofTechnology ResearchAssistant

ScottLabergeNorthernAlbertaInstituteofTechnology/UniversityofAlberta

ResearchAssistant

Otherfinancialsupportersofthiswork:NaturalSciencesandEngineeringResearchCouncilofCanada(NSERC)AppliedResearchandDevelopmentGrantandAlbertaInnovates


OptimizingtheUseofTubifextoEnhanceDensificationandStrengthofOilSandsTailings:BuildingonRecentLaboratoryTestSuccess,TowardsPilotCOSIAProjectNumber:TE0040(IOSI2016-08)

ResearchProvider:DeltaresandUniversityofAlberta

IndustryChampion:SuncorEnergyInc.

IndustryCollaborators:CanadianNaturalResourcesLimited,Imperial,SuncorEnergyInc.,SyncrudeCanadaLtd.,TeckResourcesLimited

Status:Year2of3

PROJECTSUMMARY

Tubifex is an anaerobic earthworm with the capability to live under various chemical, biological, and soilenvironments.Whenaddedtosediment,Tubifex“swims”andcreatesanetworkofsmallchannels.Accordingly,thehydraulicconductivityofthesedimentincreasesleadingtoenhancementoftheself-weightconsolidationrateandtheshearstrength.Whileproventobeeffectiveinacceleratingtheconsolidationofloosedeltaicandcoastalsediments inEurope, theeffectivenessofTubifex inconsolidationofoil sandstailingshadnotbeentesteduntil2014.Preliminaryproof-of-conceptexperimentsconductedin100mLbeakersbyDeltaresin2014,thefirsttestingoftheTubifexonoilsandstailings, indicatedthatTubifexcouldsurvivethetailingsenvironmentandthat itwascapableofenhancingconsolidationanddewateringrateoftailings.ThisinitialfindingwarrantedfurtheranalysisoftheperformanceofTubifexatlargerscalecolumnsandundervariableconditionsaspartofthecurrentphaseofwork.Theultimateobjectivesofthisscopeofworkwereto:

1. OptimizeTubifexsurvivalandreproductionintailingsenvironment;2. QuantifytheultimatesolidscontentandshearstrengthsachievedbyaddingTubifextotailings;and3. Gathercriticalinformationaboutfeasibilityandscale-uptooperationalconditions.

Deltares (Netherlands) and University of Alberta (Canada) are the joint technical team for delivering theseobjectivesthroughthefollowingtasks:

Task 1 (Deltares): Perform small-scale tests to evaluate the effects of temperature, tailings type, and solidscontentondewateringandstrengthgainoftailingsmixedwithTubifex.

Task2(Deltares):Performaseriesofbeakertestswithdifferentbiologicalparameters(i.e.,nutrientsandorganicmatter)forexploringoptimization/survivalofTubifexreproductioninoilsandstailings.

Task3(Deltares):Performasecondseriesofsmall-scalecolumntests,similartotask1,withdifferentdensitiesofTubifexandatoptimizedconditionsestablishedinTask2.


Task 4 (University of Alberta): Perform large-scale column tests with optimal parameters from Tasks 1-3 toevaluate the consolidation and dewatering of tailings. These data will provide a basis for future pilotimplementationifnecessary.


Thefollowingdescribestheachievementsmadetodateinthisprojectforeachtaskdiscussedabove.

Task1: Complete–Small-scalecolumntestswereconductedtostudytheeffectsofTubifexondewateringandconsolidationinfluidfinetailingsandthickenedtailingsat10°Cand22°C.

Task2: Complete–Aseriesofbeakertestswereperformedtostudytheeffectsofseveral“feedingstrategies”,including low quality organic matter, high quality organic matter, inorganic nutrient (two concentrations), onreproductionoftheTubifexworms.

After completion of Task 2 in June 2018, the project team found studies indicating that Tubifex is a carrier ofwhirlingdiseaseandcommunicatedthisfindingtotheInstituteforOilSands Innovation(IOSI)andCOSIA. Afterdiscussions with IOSI/COSIA members, it was concluded that further research on using Tubifex to enhanceconsolidationofoilsandstailingsshouldbediscontinued.Instead,literaturewasreviewedtoidentifyandselectalternative “safe” species with similar characteristics to those of Tubifex. Based on the literature (see someselected references in the following sections) and after consultation with experts of the field, Lumbriculusvariegatus(LV), also known as the blackworm,was selected as the alternative to Tubifex going forward in theproject.LV,whichisanaquaticspeciescapableofsurvivingharshenvironments,doesnotcarrywhirlingdiseaseaccordingtothestateofknowledgeatthemoment.

Inordertoaccommodatethechangesdescribedabove,theprojectteamsubmittedascopechangedocumentinJuly2018topursuetherestoftheprogramwithLV.ThechangeofscopewasacceptedbyIOSI/COSIAonOctober16,2018.Projectactivitiesareplannedtoresumebeforetheendof2018.

Tasks3and4:Noactivitieshavebeenperformedgiventhefindingsandchangesdescribedabove.

LESSONSLEARNED

The results of the project shows that Tubifex improves the dewatering properties of oil sands tailings in alaboratoryenvironmentandthatTubifexcanliveandreproduceinoilsandstailings.SinceTubifexisfoundtobeacarrierofwhirlingdisease,theeffectivenessofLVondewateringandconsolidationoftailingsshouldbetestedasthe next steps of the project. If testing of LV finds it effective, it will be used to study dewatering andconsolidationoftailingsinlargecolumnsattheUniversityofAlberta(Task4).

LITERATURECITED

Brinkurst,R.O.1976.AquaticoligochaetarecordedfromCanadaandtheSt.Lawrencegreatlakes.PacificMarineScienceReport76-4.Downloaded9-8-18fromwww.dfo-po.gc.ca/Library/54831.pdf


Brinkhurst,R.O.1996.OntheroleofTubificidoligochaetesinrelationtofishdiseasewithspecialreferencetotheMyxozoa.AnnualReviewofFishDiseases,Vol.6,pp.29-40.

Granath, W.O. Jr., M.A. Gilbert. 2002. The role of Tubifex tubifex (Annelida: Oligochaeta: Tubificidae) in thetransmissionofMyxoboluscerebralis(Myxozoa:Myxosporea:Myxobolidae).In:BartholomewJ.L.andWilson,J.C.(eds.)Whirlingdisease:Reviewsandcurrenttopics.Am.Fish.Soc.Symp.29.AmericanFisheriesSociety,Bethesda,MD,pp.79−85.

Marchese,M.R.,M.R.dosSantos,J.C.dosSantosLima,andP.A.ZaitunePamplin.2015.FirstrecordofintroducedspeciesLumbriculusvariegatusMüller,1774(Lumbriculidae,Clitellata)inBrazil.BioInvasionsRecords4:81–85.doihttp://dx.doi.org/10.3391/bir.2015.4.2.02.

Pickavance, J.R. 1971. The ecology of Lumbriculus variegatus (Müller) (Oligochaeta, Lumbriculidae) inNewfoundland.CanadianJournalofZoology,1971,49(3):337-342,https://doi.org/10.1139/z71-049.

Özer,A.andR.Wootten.2000.ThelifecycleofSphaerosporatruttae(Myxozoa:Myxosporea)andsomefeaturesofthebiologyofboththeactinosporeanandmyxosporeanstages.Dis.Aquat.Org.40:33-39.

Özer,A.,R.Wootten,andA.P.Shinn.2002.Surveyofactinosporeantypes(Myxozoa)belongingtosevencollectivegroupsfoundinafreshwatersalmonfarminNorthernScotland.FoliaParasitologica49:189-210.

Urawa, S.,M.A. Freeman, S.C. Johnson, S.R.M. Jones, and H. Yokoyama. 2011. Geographical variation in sporemorphology, gene sequences, and host specificity ofMyxobolus arcticus (Myxozoa) infecting salmonid nervetissues.Dis.Aquat.Org.96:229–237.


Sittoni, L.,M.De Lucas Pardo, and J. Hanssen. 2018. Enhancing densification and strength ofOil Sands TailingsdepositsbyusingTubifexworms.Successessofar.OilSandsInnovationSummit2018,Calgary,Alberta.

de Lucas Pardo, M., X. Yang, M. Ibanez, and L. Sittoni. 2016. Tubifex: a biological method for enhancingdewatering oil sands tailings. Latest results and next steps. Conference proceedings International Oil SandsTailingsConference2016,280-286.

Yang, X., M. de Lucas Pardo, M. Ibanez, L. Deng, L. Sittoni, A. Ulrich, and Q. Chen. 2016. Addition of Tubifexacceleratesdewateringofoilsandstailings.CanadianJournalofCivilEngineering,43(12),1025-1033.

Yang, X.,M. de Lucas Pardo, L.Deng, L. Sittoni, A.Ulrich, andQ. Chen. 2015. Tubifex: a biologicalmethod fordewateringoilsandstailings.ConferenceproceedingsTailingsandMineWaste2015,499-507.



Institution:DeltaresandUniversityofAlberta

PrincipalInvestigator:MiguesdeLucas,Deltares


orJobTitle

DegreeStartDate

(ForStudentsOnly)


(ForStudentsOnly)

MigueldeLucas,AlexKirichek, Deltares,theNetherlands ResearchScientist

PeterHerman Deltares,theNetherlands SeniorAdvisor LucaSittoni Deltares,theNetherlands ProgramManager AniaUlrich UniversityofAlberta,Canada Professor LijunDeng UniversityofAlberta,Canada AssistantProfessor


DevelopmentofRapidScreeningMethodsforMatureFineTailingsCOSIAProjectNumber:TE0043(IOSI2016-12)

ResearchProvider:PurdueUniversity

IndustryChampion:CanadianNaturalResourcesLimited(CanadianNatural),Imperial

IndustryCollaborators:SyncrudeCanadaLtd.,SuncorEnergyInc.,TeckResourcesLimited

Status:Year1of1

PROJECTSUMMARY

The growing inventory of mature fine tailings (MFT) is the focus of large-scale efforts to reduce the volumethrougharangeoftreatmentoptions.AnalysisofMFTgenerallyrequiresdetailedandtime-consuminglaboratoryanalysestoobtainpropertiesneededforeffectivetailingsmanagement. Forthisproject,asetofspectroscopic-and thermal analysis-based rapid scanningmethodswere used in combinationwith chemometricmodelling torapidlypredict keypropertiesneeded foreffective tailingsmanagement. Theproposedmethods couldbe fielddeployedonsiteandsomeoftheproposedmethodscouldbepotentiallyfurtherdevelopedasin-linesensors.

EffectivestewardshipofMFTiscentraltooilsandsmining.ThegrowinginventoryofMFT(~109m3)isthefocusofexploringarangeoftreatmentoptionsthatincludetheadditionofpolymericflocculants,coagulants(e.g.,alum,gypsum),acombinationof ‘stackedtechnologies’—inawiderangeofengineeringsolutionsthat includethin-liftdrying, centrifugation, electrokinetic dewatering, and solid-liquid separation technologies—in order to achievereclamationgoals.TailingsmanagementrequiresanalysisofMFTthatoftenincludedetailedandtime-consuminglaboratory analysis in order to obtain key tailings properties such as water chemistry, bitumen content,solids/clay/watercontents,particlesize,andclaymineralogy.

Thisprojectexploredtheapplicationofarapidscreeningmethod(RSM),attenuatedtotalreflectance(ATR)FTIR(Fouriertransforminfrared),spectroscopythathasthepotentialtobefielddeployedonsite.Theprojectfocusedon collecting experimental data in the laboratory using spectroscopic- and thermal analysis-based methods inconjunction with available data sets. Chemometric models were built from the RSM data to predict tailingspropertiesof interest. SomepropertieswerestronglycorrelatedwiththeRSMdata;e.g.,methyleneblue index(MBI),butotherproperties(e.g.,quantificationofillite)wereweaklycorrelated.Thestrengthofthesemethodsisthattheyprovidemulti-dimensional(claytypeandamount,bitumenandwatercontent)informationfromasingletypeofanalysis.

FTIRmethodshaveattractedsignificantinterestinthepast10yearsasarapid,low-costassessmenttoolinoilandgasapplications(Breenetal.2008;Herronetal.2014). Thestrengthofthismethod is inthatallmineralshaveabsorption bands in themid-infrared (mid-IR) region and some of these spectral features are highly diagnostic(e.g., kaolinite,quartz). Moreover,waterandbitumenbothhavecharacteristicabsorption features inboth themid-andnear-IRregions(SchoonheydtandJohnston,2013;Nikakhtarietal.2014;Osackyetal.2013).


Inanutshell, thedesignandmethodologyforthisresearch istocollectbothspectroscopicandthermalanalysisdata(referredtoasRapidScreeningMethodorRSMdata)ofMFTwithdiversebitumen/water/mineralcontentsandMBI vales. For themid-IR andnear-IRmeasurements diffuse reflectance (DR-FTIR)method is used for drypowderedsamples,andattenuatedtotalreflection(ATR)methodisusedforbothdryandMFTslurries.Thermalanalysisiscollectedfromthesesamplesassolidsand/orslurries.Then,chemometricmodellingisusedtorapidlypredict key properties needed for effective tailingsmanagement. Potentially, the proposedmethods could befield-deployedonsiteandsomeofthemfurtherdevelopedasin-linesensors.Thestrengthoftheproposalisthatmulti-dimensional (clay type and amount, bitumen andwater content) information is obtained from the sameanalysis.

Validationofthespectroscopicandthermalanalysismethodswillrelyonstatisticalmethodstoderivepredictiverelationshipsfromthemeasureddatawithoperator-orPurdue-providedanalyticaldata(e.g.,quantitativepowderX-raydiffraction,MBI,clay-to-waterratio,yieldstress).Chemometricmethodswhichwillbeusedinclude,butarenot limited to, partial least squares (PLS), simple Beer’s law, classical least squares (CLS), stepwise multipleregression (SMLR), principle component regress (PCR) and principle component analysis (PCR) analyses. The‘whole spectrum’methods, likePLSandPCR,havebeendemonstrated tohave improvedpredictiveabilityoveranalysisofdiscretespectralbandsandregions(simpleBeer’slaw)(Igneetal.2010;Vasquesetal.2008).Usingaleave-one-out analysis, predictive relationshipswill be established formineral constituents,water content, andbitumencontentbasedon‘actualversuspredicted’correlations.FurtherexplorationofthesemethodstopredictMBI, overall clay content, clay-to-water ration, and particle sizewill be explored. Rapid prediction of keyMFTparameterswillbeevaluatedbasedon theprecision,accuracyand reproducibilityofderivedparameterswithinthecontextofthesamplepreparationandpresentationtime.

OBJECTIVES

1. SourcecontrastingMFT.2. DevelopsamplingprotocolsandcollectstatisticallyrelevantRSMdatafromsourcedMFT.3. DevelopandoptimizepredictivechemometricmodelsbasedoncollectedMFTRSMdata.4. Validationofchemometricmodels.Workingwithoperators,blindsampleswillbeprovidedandtargeted

propertieswillbepredictedbasedonthechemometricmodelsdevelopedunderObjective3.5. Short-listingofRSMandchemometricmodels.


Weobtained six tailings samples in 2018 in collaborationwith Abu Junaid (CanadianNatural) alongwith somecharacterizationdata (seeTable1below). Inadditiontothe“new”MFT, fivewell-characterizedMFTwerealsoincluded. Mid-IRanalysiswascompletedusingDR-FTIRforpowderedsamples,singleandmultiplebounceATR-FTIRspectra fromsolidandMFTsuspensionsandthermogravimetricanalyzer (TGA)analysiswasobtained inaninert(i.e.,N2)atmosphere.

Priortothisproject,RobMahoodandAbuJunaidprovidedasetof100drysamplesfromtheAlbianProjectthatrepresented geology, tailings and process stream samples. In order to inform the spectroscopic and thermalanalysis methods used in the current project, we revisited these samples because there was extensive


characterizationworkdoneonthesesamples,whichiscurrentlyownedbyCanadianNatural. Thedataincludedquantitativeclayandbulkmineralogy,particlesizeandMBItesting.

Table1.CurrentandLegacyMFTsUsedinThisProject

BucketLabel MBImeq/100g Bitumen(%) Water(%) Mineral(%)

CNUTSUPS1730(ES-4081) 6.8 2.4 77.6 20.1

CNUTSUPS1727(ES-4093) 6.9 2.4 71.8 26.0

CNUTSUPS1729(ES-4091) 7.9 2.4 68.5 29.3

CNUTSUPS1734(ES-4099) 8.1 2.0 72.1 26.0

CNUTSUPS1731(ES-4100) 9.3 2.1 79.4 18.2

CNUTSUPS1725(ES-2774) 11.5 1.6 67.0 31.58A 10.5 - 68 -

2/3 8.6 - 50.9 -

2/3F 8.4 4.7 64.3 31

SHELL 11.0 1.5 65.1 33.4

STP 11.2 1.1 66.5 32.4

Thedatacanberepresentedas:

One interesting result from this analysis is shown belowwhereMBI valueswere predicted based upon diffusereflectance(DR)FTIRspectroscopy.


Thekeyresultsfromthisanalysisareshownbelow:

GoodcorrelationswerefoundforMBI,kaoliniteandquartz.K-feldspardoesnothaveuniquespectralsignature;asexpected,thedatawerenotcorrelated.Becausetheseearliersampleswereprovidedasdrypowdersandsomeof the samples had been subjected to Dean-Stark extraction, we were not able to predict water or bitumencontent.

In thecurrentproject, theMFTsamplesweresampledafter sufficientmixing. Theattenuated total reflectanceFTIRmethoddoesnotrequireanysamplepreparation.Samplescouldbeanalyzedas-receivedslurries,orasdrieddeposits, using a Pike “Gladiator” single-bounce, diamond ATR crystal. For analysis using DR-FTIR andthermogravimetricanalysis,sampleswereallowedtoairdry.


ArepresentativeFTIRspectrumofadryMFTsamples isshowbelow. Startingonthe leftsideofthefigure,thesharpn(OH)bandsbetween3700-3600cm-1correspondtothestretchingbandsofhydroxylgroups inkaoliniteandillite.Thebandsbetween3050and2800aretheν (C-H)bandsfrombitumen.Waterbandsappearbetween3400-3100cm-1andaround1630cm-1.Carbonatebandsarefoundbetween1500-1400cm-1.Strongstructural ν (SiO) bands of clayminerals are found between1200-1000 cm-1, and thecharacteristic “quartz doublet”bandsoccurat800and780cm-1.This illustrates that FTIR spectracan be used to identify clay,bitumenandwaterinMFT.

Using these methods, wecharacterized the MFT shownaboveinTable1.

Ourfirstobjectivewastoobtainconsistentsamples.DataareshownbelowforDR-FTIRspectraoffivereplicatesoftheMFTshowninTable1.WeselectedtheseMFTbecausewehadmoreextensivecharacterizationdatathanfortheCNU-TSUPsamples.


WefollowedasimilarapproachusingTGAandATR-FTIR.

We then applied discriminant analysis (principalcomponent analysis [PCA]) methods. Results areshown on the right. As the plot indicates, the MFTshow distinct groupings, meaning that they arestatisticallyresolved. The95%confidenceellipsesarealso shown. Thus, with no “user intervention” thesedatainformusthatspectralcharacteristicsoftheMFTarestatisticallydifferent.

Theproject suppliedMFTwere somewhat uniform innature. MBIvaluesranged6.8to11.5%andbitumencontents ranged from 1.6 to 2.4%. The resultsincludingthe“projectsupplied”MFT listed inTable1,the MFT showed no clearly resolved spectradistinctions.

-15 -10 -5 0 5 10 15 20 25-15

-10

-5

0

5

S1730 S1725 S1731 S1727 S1729 S1734 2/3 8A 2/3F STP SHELL 95% confidence ellipse(Mean) 95% confidence ellipse(Mean) 95% confidence ellipse(Mean) 95% confidence ellipse(Mean) 95% confidence ellipse(Mean)

PC

2

PC1


CONCLUSIONS

• Replicatedspectroscopicandthermalanalysisdatawerecollectedfrom11MFT(considerablymoredatahavebeencollectedbecausewehavealsousedthesemethodstolookatpolymer-treatedMFT).

• ThesemethodsprovidesomemechanisticinsightaboutMFTcomposition.

• Partial leastsquaresmethodsweresuccessfullyappliedtopredictkeypropertiesof~90AlbianProjectsamples(runasdrypowders).Themodelwasableto‘predict’MBI,kaolinite,quartzandclay–butnototherconstituents(e.g.,illite).

• DiscriminantanalysisofspectroscopicandthermaldatawasabletodistinguishfivecontrastingMFT(butnotforsixsimilarMFT).

• Datahavebeencollectedonslurries“asis”.

IMPLICATIONS

BecauseFTIRspectracanbeobtainedrapidly,withsuitablecalibrationandchemometricmodelling fromrobustdatasets(e.g.,quantitativeXRD,particlesizeanalysis,MBI),theproposedmethodscanpotentiallyprovidearapidandreliablescreeningtooltomonitorkeyMFTpropertiesofinterest.

LITERATURECITED

Breen C, Clegg F, Herron MM, Hild GP, Hillier S, Hughes TL, Jones TGJ, Matteson A, Yarwood J. 2008. BulkmineralogicalcharacterisationofoilfieldreservoirrocksandsandstonesusingDiffuseReflectanceInfraredFourierTransformSpectroscopyandPartialLeastSquaresanalysis.JournalofPetroleumScienceandEngineering60(1):1-17

HerronMM,LoanM,CharskyAM,HerronSL,PomerantzAE,PolyakovM.2014.KerogenContentandMaturity,MineralogyandClayTypingfromDRIFTSAnalysisofCuttingsorCore.Petrophysics55(5):435-446

IgneB,ReevesJB,McCartyG,HivelyWD,LundE,HurburghCR.2010.Evaluationofspectralpretreatments,partialleast squares, least squares support vector machines and locally weighted regression for quantitativespectroscopicanalysisofsoils.JournalofNearInfraredSpectroscopy18(3):167-176

NikakhtariH,Wolf S,ChoiP, LiuQ,GrayMR.2014.MigrationofFineSolids intoProductBitumen fromSolventExtractionofAlbertaOilsands.Energy&Fuels28(5):2925-2932

OsackyM,GeramianM,IveyDG,LiuQ,EtsellTH.2013.MineralogicalandchemicalcompositionofpetrologicendmembersofAlbertaoilsands.Fuel113:148-157

SchoonheydtR.A., Johnston,C.T. 2013. Surfaceand interface chemistryof clayminerals. In:Bergaya, F., Theng,B.K.G.,LagalyG(eds)HandbookofClayScience.2ndEdition,PartA.Fundamentals.Elsevier,Amsterdam,pp139-172


Vasques,M.,Grunwald,S.,Sickman,J.O.2008.Comparisonofmultivariatemethodsforinferentialmodelingofsoilcarbonusingvisible/near-infraredspectra.Geoderma146(1GÇô2):14-25


Institution:PurdueUniversity

PrincipalInvestigator:Prof.CliffT.Johnston,Earth,AtmosphericandPlanetarySciences

NameInstitutionorCompany

DegreeorJobTitle

DegreeStartDate

(ForStudentsOnly)


(ForStudentsOnly)

MohammadhasanSasar PurdueUniversity PhDCandidate 2014 2019


PotentialApplicationofVoluteScrewPressFiltertoTreatOilSandsFluidFineTailings–Phase2COSIAProjectNumber:TE0044

ResearchProvider:UniversityofAlberta

IndustryChampion:SyncrudeCanadaLtd.

IndustryCollaborators:CanadianNaturalResourcesLimited,Imperial,SuncorEnergyInc.,TeckResourcesLimited

Status:Year1of1

PROJECTSUMMARY

In the Phase 1 work performed with the new Volute Screw Press (VSP) filter, the capability of continuouslyproducingafiltercakeofmorethan60weightpercent(wt%)solidsandafiltrateoflessthan1wt%solidsfromfluidfinetailings(FFT)wasdemonstrated.Itwasfoundthatthepre-treatmentofFFTwithchemicalschemeswasthekeyfactortodeterminingthefiltrationresultswiththeVSP.Also,anewcontrolledverticalstraintest(CVST)devicewasdevelopedtoprovidegoodcorrelationwiththesolidscontentofVSPfiltercake.TheCVSTvaluescouldpotentiallybeusedtoidentifypromisingchemicalschemesaheadoftheVSPtests.

InPhase2,themainobjectiveistoinvestigatedifferentchemicalschemesthatcouldresultinaVSPfiltercakeofmorethan65wt%solidsaswellasa filtrateof less than1wt%solids. Chemicalscreeningtestsandcontrolledverticalstraintests(CVST)wereperformedtoidentifytheoptimaldosagesandcombinationsofchemicalschemes.TheCVSTdatawerecomparedagainst thecakesolidscontents fromthesubsequentVSPtests. InPhase2, thefollowing chemical schemes with a primary polyacrylamide (PAM) flocculant and a secondary chemical weretested:

A. PAMFlocculants+Coagulants;B. PAMFlocculants+Collectors;andC. PAMFlocculant+CoagulanttestedinPhase1ascontrolforPhase2.

In addition to the PAM flocculant and coagulant tested in Phase 1,more PAM flocculants and coagulants fromdifferentpolymervendorsandcollectorswereevaluatedusingtheVSPfilterinPhase2.OneoftheadvantagesoftheVoluteScrewPressisthatitrunscontinuouslyasopposedtointermittent/batchoperationasinaconventionalfilterpress.


Inthefirstfourmonthsoftheproject(JanuarytoApril2018),bench-scalesettlingtestsandCVSTwereperformedwithchemicalrecipesfromchemicalschemesA,BandCatvariousdosagesandcombinations.Optimalchemical


dosage ranges and CVST performance indicators were collected and promising recipes were identified andprioritized.

Site planning, procurement, equipment installing and commissioning, aswell as logistics took place throughoutMayandJune2018afterthetestsiteaccessagreementwassigned.AttheendofJune2018itwaspossibletorunanumberoftrialVSPteststofurtheroptimizetheprocessandfinalizethestandardoperatingprocedures.Severalimportant hardware adjustments were made and a number of equipment assessment tests were carried out.Afteroptimizingtheprocessandsetpoints,theformalVSPtestswereperformedwiththechemicalschemesA,BandCthroughoutJulytoOctober2018.Dataanalysisandreportpreparationareinprogress.

FromtheVSPtests,operatingwithchemicalschemeCsuccessfullyresultedingreaterthan65wt%solidscake,aswellasaclearfiltratewithlessthan1wt%solids.SomecombinationsfromchemicalschemeAyielded64-65wt%solids cake and a clear filtrate of less than 1 wt% solids. On the other hand, all combinations from chemicalschemeBcouldnotproduce>65wt%solidscake,withfiltratesolidsrangingfrom0.5–1.5wt%.Thereasonisunknown. However, themuch smallermolecularweightsof the collectors comparedwith the largerpolymericcoagulants could be one of the causes. It seems that the Volute Screw Press filter would require strong pre-treatedFFTflocs.

ThecompressiondatafromtheCVSTmatchedtheresultsfromtheVSPtests. ChemicalschemeCwasfoundtohavethelargestcompressionvaluethat iscloselyfollowedbyrecipesfromchemicalschemeA. Incontrast,theCVSTvalues fromchemical schemeBwere four to five timessmaller than those fromschemesAandC. ItwasdeterminedtheCVSTdatacanbeusedtodistinguishbetweenchemicalschemesspecificallyusedfortheVoluteScrewPress. Toclearlydifferentiatebetweenrecipeswithinagivenchemical scheme, further improvements inCVSTmeasurementprecisionarerecommended.

LESSONSLEARNED

Althoughitistooearlyforfinalconclusions,thefollowingarethepreliminarylessonslearnedfromthisproject:

• theVoluteScrewPress(VSP)filteriscapableofcontinuouslyproducing≥65%cakeand<1%solidsfiltratefromFFT. Pre-treatmentofFFTwithchemicalschemesandoptimallyconfiguredoperationparametersaremandatorytoachievetheseproductiontargets;and

• thecurrentVSPequipmenthasalimiteddrysolidsthroughput,whichisgoodforproof-of-concepttests.ItisadvisedtoutilizealargerVSPtoinvestigatethedrysolidsthroughputs.



Institution:UniversityofAlberta

PrincipalInvestigator:ZhengheXu


orJobTitle

DegreeStartDate

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(ForStudentsOnly)

ZhengheXu UniversityofAlberta Professor,PI

ChenWang UniversityofAlbertaPostdoctoralFellow/ProjectManager

JasonNg UniversityofAlberta ResearchAssistant WenfeiZhang UniversityofAlberta ResearchAssistant DanZhang UniversityofAlberta ResearchAssistant


MatureFineTailingsSpikingofHorizonThickenersCOSIAProjectNumber:TJ0011

ResearchProvider:CanadianNaturalResourcesLimited(CanadianNatural),Paterson&CookeCanadaInc.

IndustryChampion:CanadianNatural

Status:Completedin2015

PROJECTSUMMARY

Background

In 2014, Canadian Natural submitted a Tailings Management Plan (TMP) application to the Alberta EnergyRegulator (AER) for theHorizonmine,noting that200million tonnes (t) ofdry fines (i.e., particles less than44micronsindiameter)wouldbecapturedbyaddingor“spiking”maturefinetailings(MFT)intotheNon-segregatingTailings(NST)matrixoverthelifeofthemine.Non-segregatingtailingsareproducedbyatreatmentprocessthatincludescyclonestoseparatecoarsesandfromthefinestailingsstreams,andthickeners,tocaptureandremovewarmwaterfromthefinesintheflotationtailingsstreams.Thewarmwaterthatisremovedisthenreusedinthebitumenrecoveryprocess. Thecoarsesandandthickenerunderflowarethenmixedandcombinedwithcarbondioxide(CO2)toproduceNST.TheMFTwouldbeharvestedfromthetailingsponds.

TheNSTspikingdesignfromthe2014TMPwasbasedonaddingMFTtoNSTintheNSTpumpbox.However,anearlierpilotstudyontheimpactofaddingMFTtoNSTindicatedthepotentialforincreasingsegregationoftheNSTifMFTwasadded toNST in theNSTpumpbox. Itwas laterpostulated that treatingMFT in combinationwithflotationtailings(FLT)inthethickenerpriortomixingwiththecoarsefractionintheNSTpumpboxcouldmitigateNSTsegregation.

A2014 laboratorystudybyFLSmidth&Co. (FLSmidth)demonstratedthattheadditionofMFTtothethickenerswasfeasible. However,uncertaintiesregardingtheaccuracyofsomeoftheinputdatasuchasthesand-to-finesratio(SFR)ofthethickenerfeed,whichhadbeenalteredbytheadditionofsandandflowrate,andundertakingthethickeningtestsinbatchmoderatherthanusingacontinuoussystem,raisedconcernsabouttheapplicabilityoftheprojectfindings.Withtheseuncertaintiesconsidered,FLSmidthconcludedthatMFTcouldbeaddedtothethickenersup toaminimum feedSFRof0.8,while stillmaintaininggoodoverflowclarity (<0.5wt%solids)andhigh(>50wt%solids)underflowsolidsconcentration.

Between2010and2015 themean SFR forHorizon’s flotation tailingswas1.1,which supported the conceptofdewateringMFTinthethickenerfeed,therebyimprovingtheoverallsite-widefinescapture.


TestPurposeandHypothesis

TheobjectiveofthisprojectwastodeterminethickenerperformancewhenMFTspikingoccurredinthethickenerfeedrather than in theNSTpumpbox. Theprojecthypothesiswasthata thickener feedwithSFR>0.8canbespiked with MFT to produce NST with SFR as low as 0.8, which can be processed in the thickeners (with anavailableunitareaof0.07m2/tonne/day).

Theevaluationcriteriatobetestedwere:

• Underflowwithasolidscontentof≥55wt%• Overflowof≤0.5wt%.

TestingStrategy

Thetestsweredoneintwophases:jartestsfollowedbypilotthickenertests.Aseriesofjartestswereconductedtoevaluateflocculationperformanceoftwoindustriallyavailableflocculants.Pilotthickenertestsfollowedusinga3mhighby0.5mwidepilotthickenerandtheflocculantselectedfromthejartests.


Aflocculantwasselectedduringjartestanalysisbasedoninitialsettlingtestandoverflowclarity.

Threetestswereconductedtoevaluatetheperformanceofthepilotthickenerbeforeandafterspiking:

• Case1:Basecasesemi-continuous–feedatSFR1withoutMFT• Case2:MFTspikedcasesemi-continuous–SFRfrom1to0.8• Case3:MFTspikedcasecontinuous–SFRfrom1to0.8

O/Fwt%

U/Fwt%

YieldStress(Pa)

Claritywedge


BecauseCase3iscontinuousandprovidedthebestresults,onlythiscasewasconsideredforfurtherevaluation.The results (thickener feed with SFR of 1 spiked with MFT to SFR 0.8) summarized in the figure shows thatunderflowreachedasteadystateflowwithanacceptablesolidscontentof55wt%after40minutes.Thetargetvalues for solids content and clarity were difficult tomeet at the start of the test and declined over time (75minutes). This was likely a result of particle size distribution shifting to more fine solids. The problem withoverflow clarity of spiked thickener feedwas further evaluated in a different studywhich showed that using adifferentflocculantwouldimprovetheoverflowclarityresultinginmeetingthetargetvalue.

Tomitigatepotentialpumpingissues,ashearloopwithaflowrateof45L/minwasimplemented.Thisloweredthe yield stress to an acceptable value of about 30 Pa. Themeasured yield stress of the collected underflowsamplesafter24hourswasapproximately60Pa.

LESSONSLEARNED

These results support the hypothesis that spiking the thickener feedwithMFT,whilemaintaining the requiredoverflowandunderflowsolidscontents,isfeasible;specificallyatanoperationalenvelopeofSFR0.8to1.2andathigherflocculantdosagesthanthecurrentpractice(1.5timeshigherdosage).

Introducingclaystothethickenerfeedmightalsochangethecharacteristicsofthethickenerunderflow,resultingin different geotechnical characteristics such as hydraulic conductivity, dewatering and consolidation of theproducedNST.GeotechnicalanalysisandthesimulationofconsolidationbehaviourofspikedNSTisthesubjectofthestudy,SpikedNSTDepositionMonitoring(COSIAProjectNumberTJ0099).



orJobTitle

DegreeStartDate

(ForStudentsOnly)


(ForStudentsOnly)

RezaSalehiCanadianNaturalResourcesLimited

ProcessEngineer-ProjectLead

JohnClark Paterson&CookeCanadaInc. ProcessEngineer

FerdinandWidjojoCanadianNaturalResourcesLimited

ProcessEngineeringStudent


ThickenedTailingsRe-flocculationandMixingTestsCOSIAProjectNumber:TJ0013andTJ0075

ResearchProvider:CoandaResearch&DevelopmentCorporation

IndustryChampion:Imperial

IndustryCollaborators:CanadianNaturalResourcesLimited(CanadianNatural)

Status:Complete

PROJECTSUMMARY

Imperial’sKearlFineTailingsTreatment(KFTT)currenttailingsmanagementstrategyinvolvessecondarychemicaltreatmentofthickenedtailings(TT)fromthethickenerunderflow.Thickenedtailings(TT)fromtwothickenersaretransportedtothedepositionareaviaapipelineapproximately6kminlength.TheTTmustbere-flocculatedtobuild floc structure after pipeline and pump shear. Secondarymixer and polymer injection takes place 1.5 kmfromthedepositionarea.Themixer,locateddownstreamofthelastpump,shouldprovideturbulentflowinthemixerthroatwhilstminimizingpipelineshearpostflocculation. PreviousstudiesbyCOSIAonlyevaluatedin-linemixingof fluid fine tailings (FFT). Thecurrentstudy focusedon in-line flocculationofTT. Theobjectivesof thestudyincluded:

• evaluatinginlinemixingofpolymerforTT,flocbreakageduetoshearpriortodeposition;and

• determiningrequiredmixingenergiesfordifferentTTcompositionswiththeoverallgoalofvalidatingtheadequacyoftheinlinemixingrig.

Thestudywasdividedintotwophases:

PhaseI:Batchmixingstudy

Phase I consistedofa seriesofbatch flocculation tests ina315mmmixing tankusingTTmaterialwithvaryingproperties. Theresultsof thebatchtestsprovidedanunderstandingof theeffectof feedvariability (i.e., slurrydensity, clay content, and rheology) of the initial TT on the mixing parameters that define successful TT re-flocculationperformance.TheresultswereusedtodefinetheoperationwindowforTTinlineflocculation.

PhaseII:In-linemixingstudy

ThefocusforPhaseIIwasaseriesofselectedin-lineTTflocculationteststovalidatetheperformanceoftheKearlinjectordesignforTTre-flocculationatareducedscale(1/10thof field),andforaselectedrangeofrelevantTTmaterial properties, based on the results from Phase I. The in-line rig was well instrumented to allowmeasurement of velocity and floc structure. These laboratory scale in-line flocculation testswere expected toprovidealinkbetweentheTTre-flocculationprocessandtheMFTflocculationprocess,forwhichextensivein-lineinjector laboratoryand field scaledataandperformancecorrelationsexist. Thiswouldenablebuilding linkages


betweenlaboratorytankmixingandinlinemixing.Toassesstheeffectofpipelineshearonflocbreakage,sampleswere collected at the end of pipe andwere exerted to additional shear in a Couette cell. Results led to betterunderstandthepotentialimpactofpipelinelengthpostflocculation.


Theprojectwascompleted in2016and resultswere instrumental indesigningan integrated tailingspilot studyconductedatCanadianNatural’sAppliedProcessInnovationCentre(APIC)researchfacility.LessonsderivedfrombothstudyphaseswereintegratedtoinformcommissioningoftheintegratedKFTTsystem.

NoshowstopperswereidentifiedforflocculatingTTinline.Thestudyshowedlengthtodiameterratio(L/D)intheinjectorthroatisimportantforensuringsufficientpolymermixingforgoodflocculationperformance.However,iftheflowisturbulentpostinjector,theeffectivelengthisextended.TheCouetteresultshighlightedthatshearcanpotentiallyinhibitinitialdewatering.MovingtheinjectionlocationclosertothetailingsdisposalareacouldreducetheimpactofpipelineshearbutneedstobeconfirmedafterKFTTstartup.

LESSONSLEARNED

The study showed the importance of maintaining adequate throat L/D for the injector to ensure optimumflocculation. For injector design, longer injector throat and increasing the injection ports from three to fouryielded better flocculation. Optimizing shear is critical both during and post flocculation to ensure gooddewatering.Itwasalsoobservedthatflocbreakageundershearwasdependentonthequalityoftheflocsandthefocused beam reflectance measurement (FBRM) was a useful tool for monitoring flocculation performance byenablinggenerationoftherelationshipbetweenshearrateandflocsize.



SakuhuniG,RenW,MattsonK,Gallow,K,HickmanS,Rennard,D.2016.SecondaryChemicalInjectordesignandmixingstudies.TailingsEnvironmentalPriorityArea(TEPA).

Hickman, S, Sakuhuni G, Rennard, D, Gallow, K. 2017. Small scale experiments to determine performance offlocculation inKearlFineTailingsTreatmentsecondarymixersandpipelines.ProcessDevelopmentandscaleupenterprisessymposium,TheWoodlands,TX.

Rennard et al. 2016. Thickening andRe-flocculationpilot plant. Proceedings of the Fifth InternationalOil SandsTailingsConference,pp.270-279.



Institution:CoandaResearch&DevelopmentCorporation

PrincipalInvestigators:ClaraGomez


orJobTitle

DegreeStartDate

(ForStudentsOnly)


(ForStudentsOnly)

ClaraGomezCoandaResearch&DevelopmentCorporation PrincipalInvestigator

NevilleDubashCoandaResearch&DevelopmentCorporation Researcher

KonstantinPougatchCoandaResearch&DevelopmentCorporation Researcher

GivemoreSakuhuni Imperial Researcher WeiRen Imperial Researcher DavidRennard Imperial Researcher

GavinFreemanCanadianNaturalResourcesLimited Researcher


AcceleratedFluidFineTailingsConsolidationwithElectrokineticsCOSIAProjectNumber:TJ0016

ResearchProvider:ElectroKineticSolutionsInc.(EKS)

IndustryCollaborators:AlbertaInnovates,SustainableDevelopmentTechnologyCanada,CanadianNaturalResourcesLimited(CanadianNatural),SuncorEnergyInc.

Status:Lab-scalePilot-Complete,FieldDemonstration-Ongoing

PROJECTSUMMARY

ElectroKinetic Solutions, Inc. (EKS) (http://electrokineticsolutions.com/) has developed a technology for in situdewateringofoilsandsfluidfinetailings(FFT)usingelectrokinetics(i.e.,theElectroKineticSolutions–DewateringTechnology (EKS-DT)process). Starting in2011,bench scale tests confirmed thepotential forelectrokinetics todewater oil sands tailings. In 2015, EKS conducted two larger-scale tests (i.e., 130m3 and 25m3) at theC-FERTechnologies facility inEdmonton. CanadianNatural (previouslyShellCanada)andSuncorEnergy Inc.providedfinancialsupportfortheselab-scalepilottests.

The C-FER tests assessed the scalability of the technology and produced significant results in the ongoingdevelopment of this technology. The results demonstrated that EKS-DT can be scaled up and that processefficienciescanresultfromscalingup.Subsequently,EKSimprovedthedesignofthetechnologyandconductedfurther research programs to optimize the design and operation of the technology. This research resulted ininnovationsthatimproveddewateringperformanceandthemaximumachievablefinalsolidscontent.

Buildingonthedevelopmentto-dateplanningforafielddemonstrationstartinginthespringorearlysummerof2019iscurrentlyunderway.Abuilt-for-purposetestcellwillbeconstructedinearlyspring2019attheInnoTechAlbertaVegrevilleresearchfacility(Figure1.).Thetestcellwillbea20mx25mand6mdeepandfilledwitha4.5mlayerofFFT,whichwillbeoverlainbya1.5mwatercap.

This field testwill demonstrate the capability of the technology to operate year-round and to achieve a stablegeotechnicalstatesuitablefor finalreclamation. Thefieldtest isexpectedtorunfor18months. Followingthedewateringprocess,comprehensivegeotechnicalandchemicalsamplingwillbeundertaken.

The field tests resultswill be used to answer the following issues that are critical for commercialization of thetechnology.

1. Thecapitalcostsoftheinstallation(e.g.,electrodearrays,powersupplysystem,controlsystem,instrumentation);

2. Theefficiency,timeandcostsassociatedwiththedeploymentoftheelectrodesarrays;3. Themaximumpowerrequirementsoverthecourseofthedewateringprocess;


4. Theenergycostsassociatedwithdifferentstagesofthedewateringprocess;5. Thedewateringrateforeachstageofthedewateringprocess;6. Theverticalmovementoftheelectrodesduringthedewateringprocess;7. TheverticalandhorizontaldensitygradientswithinthedewateredFFT;8. Theformationofcracksduringthedewateringprocess;and9. Theamountandpatternofanodecorrosionattheendofthedewateringprocess.

CanadianNatural isprovidingtheFFTforthefieldtestfromtheJackpinemine. Theinitialsolidscontentwillbeapproximately30%byweightandthesand-to-finesratio(SFR)willbelessthan0.2.

Figure1:SchematicoftheEKS-DTFieldTest


Thedetailedengineeringforthepowersupplysystem,theelectrodearraysandthecontrolsystemisunderway.The engineering design is undergoing external expert review. Procurement of the installation componentswillbegininFebruary2019.DeliveryofthecomponentstothetestcellsiteisscheduledforearlyMay2019.

To support this field test, the design for an instrumentation system has been prepared. The data from thisnetworkof instrumentswill be fedback to the control system toguide theoperationof the installationand toprovideacomprehensiveresearchdatabasefordevelopingthetechnologyfurther.Thefieldtestwillalsoprovideabasistoassessthefunctionalityoftheseinstrumentsforcommercial-scalesystems.

Concurrently, a comprehensive research program comprising small-scale and larger-scale lab experiments isunderwayincollaborationwiththeUniversitiesofAlbertaandGuelph.

LESSONSLEARNED

Amajorchallengewiththetechnologyhasbeenforecastinghowthetechnologywillscaleup.EKShasdevelopeda detailed forecasting system for scaling up the technology. This analytical system allows the following designparameterstobeforecastatdifferentscales:

• powerrequirements;• energyconsumption;• capitalcosts;


• dewateringtime;• finalsolidscontent(i.e.geotechnicalstrength);and• anodecorrosion.

Thisforecastingsystemissupportedbyempiricalresultsfromthesupportingresearchprogramsandtheextensiveliteratureavailableonelectrokinetics. Theresultsof the fieldtestwillprovidethedatarequiredtoconfirmthecalibration of the forecasting system for the design and operation of the commercial-scale applications of thetechnology.


AseriesofMicrosoftPowerPointpresentations,researchreportsandquestionandanswerdocumentshavebeenprepared.Aswell,acomparativelifecycleanalysishasbeenpreparedthatanalysestheeconomic,environmentaland social responsibility dimensions of the EKS-DT process relative to current tailings management practices.ThesedocumentsareavailablefromEKSonrequest.


Researcher:ElectroKineticSolutionsInc.


orJobTitle

DegreeStartDate

(ForStudentsOnly)


(ForStudentsOnly)

Dr.TinuAbraham EKS Researcher EdwardHanna EKS Researcher DougKimzey EKS Researcher SteveSpencer EKS Researcher JohnVandersleen EKS Researcher Prof.BassimAbassi UniversityofGuelph ExpertAdvisor Prof.TedRoberts UniversityofCalgary ExpertAdvisor

Prof.JulieShangTheUniversityofWesternOntario ExpertAdvisor

Prof.ThomasThundat UniversityofAlberta ExpertAdvisor Prof.JapanTrivedi UniversityofAlberta ExpertAdvisor

ResearchCollaborators(2011–present):AlbertaInnovates;ShellCanada(upuntilJune2017);CanadianNatural;InnoTechAlberta;SuncorEnergyInc.;SustainableDevelopmentTechnologyCanada


ClayRemovalfromFluidFineTailingsCOSIAProjectNumber:TJ0031

ResearchProvider:SyncrudeCanadaLtd.


Status:Year4of6

PROJECTSUMMARY

Fluidfinetailings(FFT)releasewateratanextremelyslowrateduetoitslowhydraulicconductivity.Itisknownthatthenegatively-chargedclays inFFTarethebadactorsduetotheirhighaffinity forwater (i.e.,hydrophilic),smallparticlesizesandlargespecificsurfaceareas.ThesepropertiesleadtoFFTdewateringandconsolidatingatanextremelyslowrate.ToaccelerateFFTdewateringandthepaceofreclamation,SyncrudeR&DconceivedtheFFTclaytreatmentprojectbytargetingthebadactorclaysinFFT.Thetheoryofthisstep-outtechnologyistousea polymeric flocculant to enlarge the effective size of clays and a collector to change the clay surfaces fromhydrophilictohydrophobic(torepelwater).Aflocculant-collectorrecipewasdevelopedforFFTclaytreatment.

TheprocessofFFTclaytreatmentcantaketwopaths.ProcessA,simplycalledclayflotation,removesclaysfromFFTbyflotationfollowedbynaturaldesiccationoftheclayfroth.Astheclayfrothrepelswater(i.e.,hydrophobic),the clay froth dewaters and desiccates rapidly. Process B, simply called clay treatment, treats the entire FFTstreamfirstwitha flocculantandthenwithacollector. ThetreatedFFT issubjectedto liquid-solidsseparation,e.g., centrifugation, filtration and/or sedimentation in a deposition cell. Syncrude Canada Ltd. has successfullyconductedlabproof-of-concepttests,smallpilottestsforclayflotation,andfieldpilottestforFFTclaytreatment.

The main objective of the project is to develop alternative technologies for deployment that would augmentcommercial technologies in the current suite of tailings treatment activities such as composite tailings, FFTcentrifugationandwatercappedFFT.


Inthelaboratoryproof-of-concepttestsofProcessA,FFTwasdilutedandconditionedwithaflocculantfirstandthenwithacollector.WhenthetreatedFFTwasaeratedtheclayfrothwasgeneratedfromtheflotationcell.Thehydrophobicclayfrothdewateredanddesiccatedrapidly,resultingin>95%solidsinthreedaysinthelab.

Thepilotclayflotationtestswereconductedinacontinuousmodeusingthesamechemicalrecipeasthatinthelabclayflotation.Alargeflumemeasuring7.32mlongx0.61mhighx0.30mwidewasfilledwithathicknessof0.61 m clay froth generated and pumped from the froth launder of the flotation machines. The clay frothsegregated after 5 hours,with the hydrophobic froth on top and the clear releasewater at the bottomof theflume. After decanting the clearwater from the flumeover the following threedays, the frothwas left in theflume formonitoring the natural desiccation. The entire clay froth deposit in the flume desiccated to 95-98%solidsinthreemonthsattheroomtemperatureof21oC.


For Process B; i.e., clay treatment for the entire FFT stream followed by physical separation (e.g., filtration,centrifugationand/orsedimentationinadepositioncell,etc.),thelabfiltrationtestshowedthatevenunderaverylowpressureof138kPa(20psi),theflocculant-collectorreciperesultedinsignificantlyfasterfiltrationratethantheflocculantalone.Buildingonthisidea,afieldtestcellof100mx100mx10mdeep(witha0.5mlayerofsandfilterunder-drainsystem)wasdesignedandconstructedforthe2017fieldtests.ThefeedFFTwasslightlydilutedto about 28% solids andmixedwith a flocculant in an inlinedynamicmixer and thenmixedwith a collector inanotherinlinedynamicmixerinsequence.ThetreatedFFTstreamwaspipelinedtofillthe100mx100mx10mdeposition cell. The clear water was released and simultaneously pumped out of the deposition cell.Consolidationofthedepositinthetestcellwillbemonitoredforseveralyears.TheinitialdepositsamplingdatashowedthatthetreatedFFTwiththeflocculant-collectorrecipehaddewateredfromtheinitial28%solidscontentto~50%solidscontentjustonemonthafterthefieldpilottestwascompleted.

LESSONSLEARNED

The labproof-of-concept testsdemonstrated that the initialdewatering rateofFFTwasacceleratedafterbeingtreatedwiththeflocculant-collectorrecipe,whichrenderedtheFFTclayshydrophobic.ThiswasindicatedbythesignificantincreaseinclayfrothdesiccationrateandfiltrationrateofthetreatedFFT.

Long-term consolidation of FFT treated with the flocculant-collector recipe in the field test deposit will bemonitoredovermanyyears;preliminaryresultsare,however,promisingasnotedabove.


Institution:SyncrudeCanadaLtd.

PrincipalInvestigator:SimonYuan


DegreeorJobTitle

DegreeStartDate

(ForStudentsOnly)


(ForStudentsOnly)

SimonYuan SyncrudeCanadaLtd. SeniorAssociate–Chemical JimLorentz SyncrudeCanadaLtd. TeamLeader BarryBara SyncrudeCanadaLtd. SeniorAssociate–Mechanical RonSiman SyncrudeCanadaLtd. SeniorTechnologist AllanChristianson SyncrudeCanadaLtd. SeniorTechnologist


EngineeredTailingsResearchCOSIAProjectNumber:TJ0033



Status:Year4of7

PROJECTSUMMARY

EngineeredTailingsResearch is seekingnewtechnologyoptions for tailings treatmentaimedat reducingcapitalandoperationalcostsandspeedupdepositconsolidationandreclamation.Beyondtheexistingtailingstreatmenttechnologies such as composite tailings (CT), paste and thickened tailings (P&TT), centrifugation of fluid finetailings(FFT),andwatercapping,etc.,thescopeofEngineeredTailingsResearchistoexploreothernewconceptsandleading-edgetechnologiesfortailingstreatment.ThescopeofEngineeredTailingsResearchvariesfromyeartoyearbasedonthepriorityofresearchactivities.Inthepastcoupleofyears,thefollowingtwoactivitieswerethescopeofEngineeredTailingsResearch:

1) Geotechnical property measurements of the low sand-to-fines ratio (SFR) products resulting from co-disposaloftailingsdirectlyfromtheextractionprocessandFFTusingmodernpasteandthickenedtailingstechnology.

2) Evaluationofnewpolymersandchemicalsforengineeredtailingsthatprovidethestate-of-artpolymericflocculantinformationforfinetailingstreatment.

Followingthesuccessfullabandsmallpilottestsofco-disposaloffreshtailingsfrombitumenextractionandlegacyFFT (asperD085)usingmodernpasteandthickenedtailings technology, thegeotechnicalpropertiesof the lowSFRco-disposalproductsweremeasuredtoevaluatetheAtterberglimits(liquidandplasticlimits),compressibilityandhydraulicconductivityofthepolymer-treatedsampleswithSFRvaryingfrom0to3.Large-strainconsolidationtestingofthesampleswascompletedforthispurpose. Thehypothesisofco-disposaloffreshtailingsandFFTisthatthedewateringratecouldbeacceleratedwiththeincreaseinSFRinthepolymertreatedco-disposaldeposit.Theobjectiveofthisactivityistoprovethehypothesisandprovidethetechnicalfoundationtofurtherdeveloptheco-disposaltechnologyinafieldscaleandeventuallyimplementthistechnologyatacommercialscale.

For the polymer evaluation, lab FFT flocculation tests were performed for 21 polymers supplied by differentpolymervendors.Theflocculantperformanceswereevaluatedaccordingtothefourestablishedsuccesscriteriaof CST (capillary suction time), yield stress, centrifuge index, and visual observationof the floc structures. Theobjectiveofthisactivityistoseekmoreeffectiveandlowercostalternativepolymersforfinetailingstreatment.



Thegeotechnicalpropertymeasurementsof the lowSFRco-disposalproductsdemonstrated that theAtterberglimits; i.e., liquid limit, plastic limit and plasticity index, decrease with the increase in SFR in the co-disposalproducts.ThehydraulicconductivitiesincreasesignificantlywiththeincreaseinSFRintheco-disposalproductsatthe same void ratio. The compressibility of the co-disposal products under the same effective stress is alsoenhancedwhen theSFR in theco-disposalproducts is increased. These resultsverified thehypothesis that thedewateringratecouldbeacceleratedwiththeincreaseinSFRinthepolymertreatedco-disposaldeposit.

The polymer evaluation tests demonstrated that three of the 21 polymers tested gave the best flocculationperformance,whichwasequivalenttotheflocculationperformanceofthepolymercurrentlyusedincommercialfine tailings treatment. This increases the flexibility and options available for chemical treatment of FFT toproducedepositsthatcanbeprogressivelyreclaimed.

LESSONSLEARNED

ThegeotechnicalpropertymeasurementsshowedthatthehydraulicconductivitiessignificantlyincreasedwiththeincreaseinSFRintheco-disposalproductsatthesamevoidratio.Thesedataprovedthehypothesisandprovidedthe technical foundation to further develop the co-disposal technology in a field scale and implement thistechnology at a commercial scale. The potential benefit of co-disposal of fresh tailings and FFT is that thistechnologynotonlytreatsthelegacyFFTbutalsocapturesthenewfinesfromthefreshtailingsgeneratedfromextraction.

The polymer evaluation results provide the polymer end users with the diversity of polymer supplies andpotentiallytheflexibilityofFFTtreatmentoperations. Itshouldberecognizedthattheassessmentsofpolymerswereforinitialdewateringonly.Furtherconsolidationandhydraulicanalysismayberequiredtogaintheinsightrequiredforlong-termdewateringratesbeforeconsideringtheseotherpolymersforcommercialoperations.



PrincipalInvestigator:SimonYuan

Name InstitutionorCompany DegreeorJobTitle

DegreeStartDate

(ForStudentsOnly)


(ForStudentsOnly)

SimonYuan SyncrudeCanadaLtd. SeniorAssociate–Chemical RonSiman SyncrudeCanadaLtd. SeniorTechnologist XinghuaMo InnoTechAlberta Researcher HaihongLi InnoTechAlberta Researcher JoeZhou InnoTechAlberta Researcher


AlternativePolymersforMatureFineTailings(MFT)DryingCOSIAProjectNumber:TJ0056

ResearchProvider:CoandaResearchandDevelopmentCorporation


Status:Ongoing

PROJECTSUMMARY

Thepurposeofthisprojectistoscreenchemicals(polymers)forsuitabilityinSuncorEnergyInc.’s(Suncor)currentTailings ReductionOperation (TRO™)mature fine tailings (MFT) drying systems,with a focus on cost reductionand/orimprovedsystemperformanceasmeasuredbyincreasedMFTdewateringratesandamountsinthefield.A field trial was conducted in 2016 at the TRO™ process to assess two different polymers, “Polymer A” and“Polymer B”, in comparison with the incumbent chemicals, “Polymer C” and “Polymer D”, respectively. Theevaluationinvolvedbenchscalecomparisonofthepolymerchemistriesinadditiontoafieldtrial.TheresultsofboththebenchtestingandfieldtrialwerecomparedagainstthemodifiedPolymerTestingProtocolandSuccessCriteria(Table1).Overallsuccessofthetrialhasbeendefinedassuperiortechnicalperformanceofthepolymeratanadvantageouscostprofileincomparisonwiththeincumbentpolymerchemistries.In2017“PolymerE”wastestedagainst“PolymerB”butwasunabletomatchorbetteritsdewateringcapabilityatasimilarorlowerdose.Testingof“PolymerE”wasdiscontinuedpriortoafieldtrial.


Comparative testing of Polymer A and Polymer B with the incumbent polymers, Polymer D and Polymer C,betweenaninitialclay-to-waterratio(CWR)rangeof0.25to0.35areshowninTable1.

Table1:PolymerTestingProtocolandSuccessCriteria(ComparativeEvaluationofResultsforanInitialCWRRangeof0.25to0.35)

PolymerDose(%Reduction)

24HourCWR(%Increase)

PolymerB:PolymerA 18 24

PolymerB:PolymerC 22 21

PolymerB:PolymerD 21 25

PolymerA:PolymerC 5 6

PolymerA:PolymerD 4 10


Twooptionswereconsideredfollowingthecomparativeevaluation:useacombinationofPolymerAandPolymerB(Option1);orusePolymerBinallplants(Option2).

Option1:UseacombinationofPolymerAandPolymerB–ThisoptionisnotthetechnicaloptimumsolutionforSuncor; however, it has commercial benefits as it encourages competitive pricing between polymer vendors.Additionally,thisoptioncapturesbusinessbenefitasitisbridgesSuncor’sOperations/TechnicalwithothertailingsresearchinitiativessuchasAcceleratedDewatering(ADW)andPermanentAquaticStorageStructure(PASS).

Option 2: Use Polymer B in all of Suncor’s plants – This option is the most technologically advantageous forSuncor;however,vendorpricingandmanufacturingcapabilityforPolymerBhasyettobeconfirmed.

ThisprojectsupportsSuncorpatentCA2820324“EnhancedTechniquesforDewateringThickFineTailings.”

LESSONSLEARNED

Lessonslearnedfromthefieldandbenchscaletrialsinclude:

• PolymerAandPolymerBoutperformedtheincumbentpolymersintermsofpolymerdosage(lesspolymerwasrequired)andthe24-hourCWR;

• Theperformanceforeachpolymerwasidenticalatdifferentscalestestedbutthelargerscaledemonstrateda30%increaseintheCWR;

• Changingmixingparametersresultsinauniqueresponsefromeachpolymer;• Nosignificantdeviationswereobservedinlaboratorydryingperformanceorstrengthgainfor

PolymerB;and• PolymerAexhibitedahigherfinalstrengthataCWR=1thanitsreferencePolymerDduringabench

scalecomparison.


Institution:SuncorEnergyInc.

PrincipalInvestigator:AdrianRevington


orJobTitle

DegreeStartDate

(ForStudentsOnly)


(ForStudentsOnly)

AdrianRevington SuncorEnergyInc. TeamLead

BennyMoylsCoandaResearchandDevelopmentCorporation ProcessEngineer


ThickenerOperationOptimizationCOSIAProjectNumber:TJ0071

ResearchProvider:CoandaResearch&DevelopmentCorporation,PocockIndustrial


Status:Year5of5

PROJECTSUMMARY

ThefocusofCOSIA’sTailingsEnvironmentalPriorityArea(EPA)isimprovingthemanagementofoilsandstailings.Improvedmanagementincludesawiderangeofactivities,includingovercomingoperationalchallengesduringthetailings treatment process. Operational challenges for oil sands tailings treatment include clay and bitumencontent as well as feed variability. At the Kearl Oil Sands mine (Kearl), Imperial selected thickeners andflocculationas theprincipal treatment technologies for its fluid fine tailings (FFT). Toassistwith theKearl finestailings treatment (KFTT) process, Imperial’s technical team performed a series of laboratory studies andprocessingtrials,including:

• thickenerfeedvariabilitytestingandthickenertestswithawiderangeofsand-to-finesratio(SFR)toextendtheoperatingenvelopeofthethickenerfrom0.5-1.2to0.5-3SFR;

• thickeningandflocculationperformancewithhighbitumenfluidtailingsfeed;• highfinesoreandtailingsfinesdistributionstudy;• semi-continuousoperatingstrategydevelopmentandimplementation;and• developinganoperatingstrategywithvaryingoilsandsorefeed.

Thepurposeofathickeneristorecoverwaterandproduceconcentratedslurry.Thus,theoverflowwaterclarityand underflow density and solids content are key process indicators of success for the fluid tailings thickeningprocess.Otherprocessvariablesmonitoredinclude:

• thickenerfeedcomposition–includingvolumetricflow,solidsrate,particlesizedistribution,claycontent,andbitumencontent;

• underflowcomposition–includingvolumetricflow,solidsrate,particlesizedistribution,claycontent,bitumencontentandyieldstress,asrequired;

• bedlevel,pressureanddensitygradient;• raketorquereading;and• flocculantdosageandconcentration.

During the KFTT process, flocculant is injected into the tailings stream upstream and downstream of thethickeners.Thebenefitsofthesecondflocculantinjectionareto:

• rebuildtheflocstructureandenhancethethickenedtailingspermeability;• reducethefootprintandvolumeforthickenedtailingsstoragethroughaccelerateddewatering;and


• increasetheyieldstressslowlyatdischargeandallowthethickenedtailingstoflowinthedepositareaandgainstrengthafterfurtherdewatering.

Optimal flocculantdosageandmixingenergy isneeded forboth the initial flocculationandre-flocculation. Theoptimal flocculant dosage is determined by the thickened tailings composition (i.e., fines or clay content) andwater chemistry. The mixing energy required depends on solids rate, thickened tailings volumetric flow anddensity, pipeline shear and injector design. With a given flocculant injector, the mixing energy required isinfluencedmorebythethickenedtailingsdensitythanthevolumetricflow.Thismeansthatthedensityshouldbecontrolledwithinadesiredrangetominimizetheimpactsofmixing.


Following the laboratory and processing trials, Imperial’s KFTT started-up successfully and the technology wasprovenata commercial scale. Duringnormaloperations, toavoid theproductionofoff-spec thickened tailingswhen the solids loading rate is consistently low, a semi-continuous operating mode was developed andimplemented. During the optimization of the thickener operation critical factors were identified that impactthickenerperformance,including:

• stablefeedandfeedvariabilitymanagement;• reliableandoperablefacilities;• instrumentationandcontrolsystems.

As the floc sizeandstructurearecritical for re-flocculationperformance,capillary suction time (CST)providesagoodmeasurementofdewateringforflocculatedmaterial.Thekeyprocessindicatorsare:

• capillarysuctiontime(CST);• initialyieldstressandyieldstressgainafter24hoursand7daysdeposition;and• solidscontentgainin24hoursand7daysfollowingdeposition.

Additionally, the thickened tailings density, flow and flocculant dosage should be monitored to ensure thegeneratedtailingsarewithinspecifications.

LESSONSLEARNED

Oilsandstailingstreatmenthasengineeringchallenges.Selectedtailingstreatmenttechnologiesshouldbeabletotreat fines tailings at an acceptable rate while maintaining short term and long term dewatering capabilities.ReductionofclayorFFT/MFTintreatedtailingsdepositscanimproveshortandlongtermdewateringcapability.FFT/MFTratio reduction in tailings feed,however,willalso reduce fines treatmentefficiency. OptimalmixesoffreshtailingsandFFT/MFTcanenhancedewateringwhilemaintainingefficientfinesstoragevolume.

Ingeneral,tailingsmixturesofmediumSFR(preferred~1),withapproximately30-40%MFTwasidentifiedastheoptimumcompositionforshort-termdewateringandlong-termconsolidation.Identificationofthecorrectrecipeshould consider both efficient fines treatment and creating reclaimable deposit in a relatively short time. Anapplicationofselectedtreatmentenvelope,with thickeningandre-flocculationprocess,canproduce favourable


depositpropertiesfortimelyreclamationandwasdiscussedindetailwithkeyprocessperformanceindicatorsandsuccessfulcommercialscaledepositperformance. Most importantly, re-flocculatedthickenedtailings illustratedthatthetreatedtailingsdepositcanbesuccessfulinbothshort-andlong-termtimeperiodswithavariablefeedrange.

LITERATURECITED

Boswell,J.R.andDavachiM.2012.Oilsandstailingstechnologydeploymentroadmap,ProjectReport,volume5.

Omotoso,O.&Melanson,A.2014. Influenceofclaymineralsonthestorageandtreatmentofoilsandstailings.Paste2014,Proceedingsofthe17thInternationalSeminaronPasteandThickenedTailings,Page269–280.

Laros, T., Slottee, S. and Baczek F. 2002. Testing, sizing, and specifying sedimentation equipment. MineralProcessingPlantDesign,Practice,andControl:Proceedings,Volume1,Page1295-1312.

Ren,W. 2018. 2018.ExpandedOperational Envelopeof ThickeningandReflocculation Through Semi-continuousOperation.Presentedat2018OilSandsInnovationSummit,Calgary,Alberta,Canada,June7-8,2018.



Ren, W. 2018. Expanded Operational Envelope of Thickening and Reflocculation Through Semi-continuousOperation.Presentedatthe2018OilSandsInnovationSummit,Calgary,Alberta,Canada,June7-8,2018.

Ren, W., Sury, K. and Clingman, S. 2014. Enhanced thickened tailings performance via additional chemicaltreatments.Paste2014,Proceedingsofthe17thInternationalSeminaronPasteandThickenedTailings,Page245–255.

Ren,W.andWeerakone,S.2018.AcceleratedOilSandsTailingsDewateringwithThickeningandReflocculation.Presentedat IOSTC2018. InternationalOil SandsTailingsConference2018,Edmonton,Canada,December9-12,2018.




orJobTitle

DegreeStartDate

(ForStudentsOnly)


(ForStudentsOnly)

WeiRen ImperialSeniorAdvisor,MineralProcessing

TineSchaffer Imperial FacilityLead

SidanthaWeerakone ImperialGeotechnicalEngineer

NevilleDubashCoandaResearch&DevelopmentCorporation Researcher

ClaraGomezCoandaResearch&DevelopmentCorporation PrincipalInvestigator



PermanentAquaticStorageStructureforFluidFineTailingsCOSIAProjectNumber:TJ0082

ResearchProvider:SuncorEnergyInc.,CoandaResearchandDevelopmentCorporation,SRKConsulting(Canada)Inc.,UniversityofAlberta,UniversityofSaskatchewan,UniversityofWaterloo


IndustryCollaborators:TeckResourcesLimited

Status:Year3of5

PROJECTSUMMARY

ThePermanentAquaticStorageStructure(PASS)projectisfocusedonthetreatmentoffluidfinetailings(FFT)tocreateasubstratethatcouldbereclaimedintoafreshwaterlakeshortlyaftertheendofdepositioninaminedoutpit. The PASS project is a multi-year, multi-stage project from concept development to concept validation atbench,pilotandfieldscales.

ThekeyresearchobjectivesofthePASSprojectinclude: identifyingthematerialsofpotentialconcern(principalparameters) thatmight impede thegeochemicalandgeotechnical stabilityofa freshwater lake;anddevelopingFFT treatment solutions to bring the parameters to levels that meet federal and provincial guidelines forfreshwaterlakes.

TheFFT treatmentprocess is a two-stepprocess. The first treatment iswithanacidic coagulant to immobilizecertain parameters, which might be of concern in a freshwater lake, such as some metals, organic acids andhydrocarbons. This is followedby theadditionofa flocculant thataids rapid releaseofwater fromthe treatedFFT.ThetreatedFFTissubsequentlyconditionedandconveyedoverseveralkilometresofpipelinetoadepositionareathatactsasasettlingbasin.

Aftertheendofdeposition,thetreatedFFTisanalogoustolakesedimentsettlingoverlongperiodsoftime.AssettlementofthetreatedFFToccurs,porewater (watersurroundingthe individualsolidparticlesofthetreatedFFT)iscontinuouslyexpressedorreleasedfromthetreatedFFTtotheoverlyingwatercap,whichisconnectedtothesurroundingwatershed. Theimmobilizationprocessensuresgeochemicalstabilityofthelakelandformsuchthatseepagethroughthepitwallsorexpressedwatertothelakewatermeetfederalandprovincialguidelinesfortheprotectionofaquaticlife.



AtreatmentprocessforFFTthatminimizesthemobilityofthekeyparametersofconcernintheenvironmentwasdeveloped. The treatment process has been validated at bench, pilot and commercial scales. Several 5 mgeocolumns are beingmonitored over a five-year period to develop predictivemodels of the geochemical andsettlementtrajectoriesofthelakelandform.

Thetreatmentprocessusesanacidiccoagulanttochemicallyimmobilize,throughprecipitationorchemisorption,dissolvedparametersofconcernsuchasorganicacidsandsomemetals,aswellastocoagulatebitumenandultrafines.ThisensuresthattheparametersofconcernarepermanentlysequesteredwithinthemineralmatrixoftheFFT. This is followed by flocculant addition to rapidly dewater FFT to enablewater recycling to the extractionplantsduringminingoperations.

A bench scale geotechnical centrifuge for simulation of treated-FFT settlement in a deep deposit was alsodeveloped.

LESSONSLEARNED

To-datetheprojecthasdemonstratedthattheFFTtreatmentprocess iscapableofacceleratingthereclamationtimelinesforaquaticlandformsfollowingin-pitdepositionofFFT.

ThebenchtopcentrifugedevelopedaspartofthePASSprojectcouldbeusedasaprocessmonitoringtoolduringdepositiontoensurethatsettlementtargetsareachievedforthemajorityoftreatedFFTplacedin-pit.



Omotoso, O. 2018. PASS: A technology solution for tailings management. Presented at the 2018 Oil SandsInnovationSummit,Calgary,Alberta,Canada,June7-8,2018(submittedtoCOSIA).



Institution:Multipleinstitutions

PrincipalInvestigator:Multipleresearchers


orJobTitle

DegreeStartDate

(ForStudentsOnly)


(ForStudentsOnly)

OladipoOmotoso SuncorEnergyInc. StrategicTechnology JonMartin UniversityofAlberta GonzaloZambrano UniversityofAlberta MattLindsay UniversityofSaskatchewan AndreaFarwell UniversityofWaterloo


MatureFineTailingsPolymerInjectorRedesignCOSIAProjectNumber:TJ0084



Status:Ongoing

PROJECTSUMMARY

The successofboth theTailingsReductionOperations (TRO™)andPermanentAquatic StorageStructure (PASS)technologies partly relies on successful flocculation of the tailings material to facilitate its dewatering. Theflocculation is achieved by the addition of polymer to mature fine tailings (MFT) flow in the in-line injector.Therefore, the effectiveness of the polymer injector (AR5) plays an important role in the process. ExistinglaboratoryandfielddataforTRO™suggestthatdewateringandpolymerdosagerequirementsareinfluencedbythemixing/dispersionofpolymerintoMFTandtheturbulencegeneratedattheinjector;wherebothcanresultinchangestothemicroandmesomixingconditionsattheinjector.Thisobservedinfluencecreatesanopportunityto improvemixing and turbulence generation through injector designmodifications to reduce polymer dosageand/or improvedewateringperformanceat a givendose. The reducedpolymerdemandwill notonly result insignificantcostsavingsbutalsoinincreasedMFTprocessingcapabilities,whichwillacceleratereclamation.


SuncorEnergy Inc. (Suncor) carriedout two field testingcampaigns to investigate theeffectofmicroandmesomixing scales onMFT flocculation and dewatering in the 2015 and 2016 seasons, respectively. Based on thefindingsofthefieldtests,acomprehensiveresearchprogramthatcomprisedbothlaboratory-basedexperimentalandcomputationalmodellingcomponentsaimedatdevelopinganimprovedinjectordesignforMFTflocculationwas initiated in2017. Theexperimentalpart focussedontheutilizationof theavailable flocculationfacilitiesatthe Coanda Research & Development Corporation (Coanda) Edmonton location to carry out flocculationexperiments for a variety of injector modifications for scaled-down versions. The modelling part includedapplicationof the toolsalreadydevelopedsuchas single-phase turbulent flowsimulations,anddevelopmentofthe sophisticated multi-phase population balance model (PBM) that would incorporate floc formation andbreakage mechanisms, flow regime transition, fractal growth of flocs and other important phenomena. Theobjective of the flocculation modelling was to gain insights about the process and provide a bridge betweenlaboratoryandfieldoperatingconditions.

Thekeyachievementsoftheinjectorredesignprogramare:

• Designandexaminationofmultipleinjectordesigns• Identificationofsuperiorinjectordesignwhichcangeneratehigherqualityflocsatalowerpolymer

dosage


• Thenewinjectordesignalsohasawiderrangeofoperationcomparedtotheincumbent(SuncororiginalAR5)

LESSONSLEARNED

Lessonslearnedinclude:

• Flocculationperformanceisastrongfunctionofinjectordesign.• Optimizationofinjectordesigncanresultinlowerchemicaldosageandimprovementinprocesskey

performanceindicatorssuchasflocsize.



PrincipalInvestigator:ArdalanSadighian


orJobTitle

DegreeStartDate

(ForStudentsOnly)


(ForStudentsOnly)

AdrianRevington SuncorEnergyInc. TeamLead ArdalanSadighian SuncorEnergyInc. ProjectLead

BennyMoylsCoandaResearch&DevelopmentCorporation

KonstantinPougatchCoandaResearch&DevelopmentCorporation


OutotecPSI500i®InstrumentFieldTestCOSIAProjectNumber:TJ0094andTJ0115

ResearchProvider:TeckResourcesLimitedCESLtestfacility/TeckResourcesLimited(TJ0094)andExxonMobilResearch/Imperial(TJ0094)

IndustryChampion:TeckResourcesLimited(TJ0094),CanadianNaturalResourcesLimited(TJ0115)

IndustryCollaborators:Imperial,SuncorEnergyInc.,OutotecOyj

Status:Year3of4

PROJECTSUMMARY

Theoilsandstailingsprocessgeneratestailingsslurrythatmustbesettledforfinaldeposition.Thetailingscontainfinematerialwithpoorwaterreleasecharacteristicsthatmakeswaterrecoverychallenging.Polymerflocculantsareaddedtoassistinsettlinganddewateringthefinetailings.Theamountofpolymeradditionisdependentonthefinefractionofthetailings.Iftheparticlesizedistribution(PSD)ofthetailingsisunknown,anexcessamountof polymer needs to be added in the dewatering stage to flocculate the fines. Over flocculation also has adetrimentaleffectonthewaterreleasecharacteristics. Measuringtheparticlesizedistributionusinganon-lineanalyzercouldhavemajorbenefitsovercommonlaboratorymethodsas itprovideson-lineandfast insight intotheprocess. This enables theoperators to implement required changes tominimize the reagent consumption,whileachievingoptimalflocculation.TheOutotecPSI500i®hasbeensuccessfullyusedinotherminingindustriestoprovidereal-timeparticlesizedistributionofslurriesbylaserdiffraction.

COSIAProjectTJ0094–AseriesoftestsusingOutotecPSI500®particlesizeanalyzeronoilsandstailingssamplesfromdifferentoperationswereconducted.Testswereperformedbyrecirculatingtheslurryinaclosedcircuittosimulaterealplantconditions.Twooftheseanalyzershavebeeninstalledatoilsandssitesbuthaveneverbeenusedcommercially.Threephasesofworkwereproposedforthisscopeofwork.

Phase 1: The existing Outotec PSI500® oil sands units were removed from site and transported to the TeckResourcesLimited(Teck)CESLtestfacilityinRichmond,BC.Oneoftheunitswascommissionedandrunthroughaseriesofteststoassesstherobustness,accuracyandoperatingrangeoftheunit.

Phase2: FoulingManagement LabProgram–Basedon theoutcomesof the firstphaseof lab testingatCESL,additional testingwas performed at the ExxonMobil Research lab to test various surfactants/solvents ability toclean fouled bitumenwindows, determine ability of surfactants to prevent fouling and effective dosage range.Sapphirewindowsweresubmersedinrelativelydiluteslurrypailswithhighbitumencontent(eitherfrommaturefine tailings (MFT)or rawoil sandsore) alongwithdifferent surfactants and solvents (sodiumdodecyl sulphate(SDS),polyethyleneglycoloctylphenyletherandadegreasercontainingamorphoussilicainwater)toseeiftheywouldreducefouling.Pailswerelightlystirredforasetperiodoftimeandthenthewindowswerequalitativelyassessedforcleanliness.


Phase3:BasedontheoutcomesofthePhase2testing,improvements/modificationsweremadetotheOutotecProbe at CESL to minimize bitumen fouling of the window. The coated window testing was done in theinstrument’sdilutiontank.

COSIAProjectTJ0115 –With thepromising results from theprevious Joint IndustryProject (JIP), a longer termtestinginthefieldisneededtofurthervalidatewhethertheOutotecinstrumentcanbeusefulforoilsandtailingstreatmentoperations.TheobjectiveofthecurrentJIPistotesttheOutotecPSI500i®on-lineparticlesizeanalyzerin the field with a few improvements and determine if this instrument is fit for the in-line tailings treatmentprocesscontrol.ThisworkwillincludeassessingPSDmeasurementperformance,foulingmitigationsolutions,andthe frequency and scope of operator intervention required tomaintain operability. The hypothesis is that theinstrumentcangiveaccuratePSDanalysiswithoutanymanualcleaningwithinaweek.

ThisscopeofworkistoinstalltheOutotecPSI500i®ontheflotationtailingslineandcontinuouslytestforatleast30days.

Theinstrumentkeyperformancewillbeevaluatedon-linethrough:

• Accuracy–theaccuracywillbemonitoredbycomparingthelaserdiffractionsignaltosamplestakenandanalyzedbyconventionalLaserDiffractionmethods

• Operatingrange–howdoestheinstrumentperformwithvariousSFRandsolidscontentrangeofflotationtailings

• Maintenancerequirement(with/withoutautomaticwiper)–howoftentheinstrumentmaintenanceandmanualcleaningisneededtoobtainusefulPSDsignal,andwhatsteps,timerequirementsandotherchallengesandopportunitiesareassociatedwiththesemaintenanceactivities

Theinformationgeneratedfromthisworkwillbeusedfortheinstrumentcommercialdesign.


COSIAProjectTJ0094

AseriesoftestworkusingOutotecPSI500®particlesizeanalyzeronoilsandssamplesfromdifferentoperationshave been conducted. Testswere performed by recirculating the slurry in closed circuit to simulate real plantconditions.ThisJIP,ledbyTeckResourcesLimited,foundthattheOutotecPSI500i®canbedesignedtoperformuseful on-line tailings particle size characterization. Fouling was the major challenge, and the method formitigatingbitumenfoulingwasinvestigated.Itwasfoundthatwithcolddilutionwater,theanalyzerranfor42hwithoutmanualcleaning.

COSIAProjectTJ0115

Forthe2018program,theinstrumentwasupgradedwithfoulingmitigationoptions(windowwipersandchemicalwash). Thesoftwarewasupgradedtoenablesettingofwiperandchemicalwassequenceandduration.Anew200mmlaserheadwasleasedandinstalled.Theupgradedsystemwasinstalled.

Itwas found that the200mm laser headperformsbetter than the300mmversion,whichwasused inCOSIAProjectTJ0094.Thelaserheadalignmentisstableandthereisnodisablingofdetectorsrequiredwhichgiveswide


measurementrangeupto1200μm.Chemicalwashandwipersystemworkswellbuttheparametersneedtobefurtheroptimized.

Theinstrumentrequiresslurryfeedrateof50-100L/minute.Itischallengingtocontrolthefeedflowratebecauseanythrottlingcausespluggingduetotheexistenceofthepetrifiedwoodintheanalyzerfeed.

LESSONSLEARNED

COSIAProjectTJ0094–Thelessonslearnedfromtheinitiallabandpilottestingincluded:

On-streamanalyzerperformedwellatdetectingdifferentsizefractionsaccurately.Goodagreementbetweenlabandanalyzerforfinefractions<44µm,andclay<10µmand<2µm.Morefocusneedstobeputondistinguishingcoarseparticlesfromairbubblestoensurethereadingsarecorrectandcorrelatewelltolabdata.

Theinstrumenthadissueswithhighbitumencontentsamples.Opticsfoulingstrategies(chemicalandmechanicalcleaning)willcontinuetobe investigatedbutthebeststrategyso far is tokeepthetemperatureof thedilutionwaterbelow20°C.

COSIAProjectTJ0115–Thelessonslearnedfromthepreliminaryfieldtestareoutlinedbelow:

Theinstrumentinstallationandconfigurationmustbeadaptedforthelocationandapplication.Thisinstrumentisverypromisingsofaranditshouldeventuallybeincorporatedinoilsandstailingstreatmentcontrolsystemswiththe proper configurations and fouling mitigation strategies. Although the analyzer itself shows promise,continuous testing has been hampered by upstream sample line plugging. In this field trial, the feed to theanalyzer is simply tapped off the mainline through a small diameter valve and pipe. The plugging issue thatoccurred in the current field trial configurationmaybeable tobe solvedby aproper commercial solution thatwouldinvolveapurpose-designedmainlinesamplesplitterthatwouldrejecttrampmaterial.



Komishke.B.2018.AdvancesinOn-linePSDMeasurementforTailings.COSIA2018InnovationSummit,June7-8,2018.Calgary,Alberta.

Schwartz,D.,Komishke,B.,Heffel,R.,Koresaar,L.,Sharifi,E.2018.EvaluationofOn-lineParticleSizeDistributionMeasurementforOilSandsTailingsTreatment.50thAnnualCanadianMineralProcessorsConference,Ottawa,ON,January24,2018.




orJobTitle

DegreeStartDate

(ForStudentsOnly)


(ForStudentsOnly)

DarrenSchwartz TeckResourcesLimited BradleyKomishke TeckResourcesLimited RoryHeffel TeckResourcesLimited JiangyingWu CanadianNaturalResourcesLimited AsharMirza CanadianNaturalResourcesLimited MichaelMarr Imperial/SuncorEnergyInc. BrentMoisan SuncorEnergyInc. DavidRennard ExxonMobil YijunLiu ExxonMobil LauriKoresaar Outotec(Finland)OY ErfanSharifi Outotec(Canada)Ltd.


PilotScaleTestProgramofNon-SegregatingTailingsEnhancementCOSIAProjectNumber:TJ0097

ResearchProvider:CanadianNaturalResourcesLimited(CanadianNatural),ThurberEngineeringLtd.


Status:Complete

PROJECTSUMMARY

CanadianNatural’sHorizonmineproducesNon-SegregatingTailings(NST)aspartofitstailingsmanagementplan.NSTtechnologyisthemaintailingstreatmentmethodadoptedbyCanadianNaturalatHorizon.NSTaretailingsthat have been treated (dewatered) to form a homogeneous, semi-cohesive mass when deposited. The NSTprocess creates a pumpable mixture of coarse sand and fines that settles rapidly, densifies, and becomestrafficableupon consolidation. The currentmethod for producingbase caseNST is touse thickenerunderflowcombinedwithasandstreamfromacycloneunderflow,whichisthentreatedwithcarbondioxide.

ToimprovetheconsolidationperformanceandreliabilityoftheNSTprocessandtoincreasefinescaptureinthetailingsdeposit,CanadianNaturalhasevaluatedvarioustechnologyoptionsthatcanbedeployedintheeventofprocessupsetsandoff-specNSTproduction.Improvingfinescapturealongwithacceleratingdepositdewateringwill result in less mature fines tailings (MFT) being generated, improve reclamation timelines—all of whichtranslatetosignificantcostsavingsoverthelifeofthemine.

Promising chemical treatment options have been tested on the off-spec NST mixture. The selected chemicaltreatmentprocessisknownasenhancedNST.TheenhancedNST(eNST)treatmentprocessisanin-lineinjectionof a selected chemical to NST upstream of the point of discharge into the deposit. Subsequent to the eNSTtreatmentprocess,andtoimprovethefinescapturecapacity,CanadianNaturaltestedinjectingMFTintotheNSTstreamtoproducealowersand-to-finesratio(SFR44)NST.ThisadditionaltreatmentisknownasenhancedspikedNST(esNST).

TheintentofthefieldpilotscaletestprogramwastocomparethegeotechnicalperformanceofNSTwithdifferentNSTenhancementmethods. Lessons learned fromtheprogramcanbe implementedat theHorizonandAlbianoperations, as well as other current or future oil sands operations interested in active tailings streamsmanagement.


KeyPerformanceMeasuresandCriteria

TheprogramobjectivesweretocomparetheperformanceofNST(asthecontrolsample),off-specNST,eNST,andesNSTmaterialsinapilotscaletestbymonitoringormeasuringthefollowingkeyperformancemeasures.

1. Thesegregationandfinescaptureperformance(solidscontent(SC)andfinescontent(FC44)).2. Theconsolidation(settlementandexcessporepressuredissipation)performance.3. Thestrength(vanestrengthandconepenetration(CPT))overthelengthanddepthofthedeposit.4. Thequalitativeperformanceduringdepositionthroughvisualobservationsandtime-lapseimages.

DesignandMethodologyoftheResearch

TheNSTpilot scale test programconsistedof separate cells for the abovenotedmaterial types. Each cellwasmonitored for deposition performance, geotechnical performance (settlement, consolidation and strength) andfinescaptureevaluationofNST,eNST,off-specNST,andesNST.NSTsubsamplesweretakenfromtheextractionplantfeedsource(i.e.,NSTLines)whichwasthentransportedviacementtruckstokeepthematerialmixedandthenoffloadedintoapumpertruckwhichthenpumpedNSTtothetestcells.Toensureallinputswereclosetooperationalconditions,plantprocesswaterwastruckedandstoredinatankatthepilotprogramsitefordilutionandtomakeupthepolymersolution.Waterandpolymersolutionwereinjectedupstreamofthedischargepointatvariousratesanddosagesinordertoreachthetargetrecipeforeachcell.


Four test cells were filled with different NST treatments. Post-deposition geotechnical performancemeasurements of the NST treatments included monitoring pore pressure dissipation, in situ strengthmeasurementsand laboratorymeasurementsfromdepositsamples. Thepiezometerdataprovided informationon the stateof consolidationof thedeposits throughdissipationofexcessporepressures. The in situ strengthmeasurementsbyfieldvaneandconepenetrometerprovidedstrengthprofilesatfourlocationsineachcell.Post-deposition sampling provided specimens to determine SC and FC44 and evaluate segregation index. Resultsincluded:

• DepositSlope:Cell#1(esNST)andCell#2(eNST)formedaslopeddepositsurface,whichwasthickeratthedischargepointandthinneratthetoeofthedeposit.Cell#4(NST)deposithadafairlyuniformthickness.

• SolidsContent(SC):Cell#1(esNST)exhibitedafairlyuniformSCoverthelengthanddepthcomparedtotheothercells.

• FC44:Cell#2(eNST)hadtheoverallhighestfinescapture,althoughFC44wasnotuniformoverthelengthofthedeposit.

• FC44:Cell#1(esNST)exhibitedafairlyuniformFC44overthelengthanddepthofthecell.Finescontentvalueswerecloseinvaluetothefeedfinescontent.

• FC44:Cell#3(off-specNST)fieldvalueswereallbelowthefieldvalueimplyingthatfineswerelostfromthecell.

• FC44:Cell#4(NST)fieldvaluesaveragedaroundthefeed,FC44isfairlyuniformacrossthelengthanddepthofthedeposit.


Followingthecompletionofthepilotscaletestprogramin2016aonedimensionalconsolidationsimulationwasconducted using available self-weight consolidation geocolumns, and large strain consolidation cells (LSC) datafrompreviousstudiestobetterunderstandandpredictthelong-termbehaviourofthedepositforeachtreatment.

Resultsfromtheconsolidationsimulationcanbesummarizedas:

• Theleastpost-depositionsettlementwasforeNST.• ThehighestporepressuredissipationratewasforeNST(itessentiallycompletesdissipationduringfilling)

althoughwithslightlylowerfinalsolidscontentduetolowercompressibility(highervoidratioathighstressrangescomparedtoNSTandenhancedspikedNST).

• Overall,thebestperformanceresultswerefromtheeNSTsimulation.

LESSONSLEARNED

Based on these findings, the eNST commercial demonstration programwas run from June 27 to September 7,2017 at the Horizon site. A total of 5.5Mt of solidswas deposited fromwhich 3.5Mtwas treated by in-lineinjection. Subsequent analyses of the annual tailings pond survey results suggest potential improvement inconsolidationandoverallfinescaptureattheHorizonsite.

TheeNSTtechnologywillbecommerciallydeployedattheHorizonsitebeginninginMarch2019.EnhancedspikedNSTwillbecommerciallypilotedfromJunetoOctober2019.



orJobTitle

DegreeStartDate

(ForStudentsOnly)

ExpectedDegreeCompletionDateorYear

Completed(ForStudentsOnly)

RezaSalehiCanadianNaturalResourcesLimited


FluidFineTailingsIn-lineFlocculationandCo-depositionCOSIAProjectNumber:TJ0108

ResearchProvider:Imperial,Paterson&CookeCanadaInc.,ThurberEngineeringLtd.,BarrEngineering&EnvironmentalScienceCanadaLtd.,Deltares


Status:Year2of4

PROJECTSUMMARY

Imperial’s research team studied the feasibility of co-depositing flocculated fluid fine tailings (FFT) into thecurrentlyoperationalthickenedtailings(TT)panels(depositareas)atKearl,Imperial’soilsandsminingoperation.Currently, Imperial’s tailings treatment plan at Kearl consists of thickening fluid fine tailings (FFT) and flotationtailings(FLT)withtheadditionofaflocculantasthetailingsentersthethickeners,followedbysecondarychemical(flocculant) treatment downstream of the thickeners and finally, deposition of the thickened (re-flocculated)tailingsinamulti-layer,deepdeposit.DewateringofthetailingsoccursduringthethickeningprocessandintheTTdepositarea.AstheTTsettlesinthedepositarea,waterisreleasedduringdepositionandsedimentationandis reused in the bitumen extraction process. The current plan includes a flocculant, thickeners, and a secondflocculant(chemical).

Co-deposition is a concept whereby FFT is flocculated in-line and then deposited in the TT deposit area. Co-deposition provides the opportunity to decouple FFT treatment from the thickener operation, and to takeadvantageofthickenerdowntimetotreatmoreFFT,asco-depositionisnotacontinuousprocess.ThefocusoftheFFT in-line flocculation and co-deposition research study is to understand and determine the limits of co-deposition without compromising; for example, by running off or displacing, any of the deposited TT or FFT-flocculatedlayers.Totesttheconcept,andpriortoundertakinganylabwork,modellingwithcomputationalfluiddynamics(CFD),movingboundarymodel(MMB)andDelft3Dwasdone.

Thekeyresearchobjectivesoftheprogramwereto:

• understandthesuccessrateofco-depositionbycomputermodelling;• modeltheconsolidationperformanceoftheTTdepositwithinterlayeredflocculatedFFT;• conductalaboratorystudytodeterminetheefficacyofthesingleflocculanttreatmentoftheFFTstream

usingthesecondflocculant(chemical)injectionpoint(downstreamofthethickeners);and• testthesettlingandconsolidationrateoftheTTdepositwiththeco-deposited(interlayered)flocculated

FFT.

The future plan for this project is to run a staged pilot in 2019/2020. For the first stage, the Alberta EnergyRegulator(AER)hasapprovedplacingflocculatedFFTeastofcurrentTTdepositareatomonitoritsperformance.

ThekeyperformanceindicatorsfortheflocculatedFFTareanincreaseinsolidscontent,consolidationbehaviour,andwaterchemistryofthereleasedwater.


For themodellingwork, Imperial contracted Paterson& Cooke Canada Inc., Thurber Engineering Ltd. and BarrEngineeringandEnvironmentalScienceCanadaLtd.,andDeltarestorunthemodels.Theresultsofthemodellingshowedthat thereare fewscenarios thatdepositing flocculatedFFTonTTorviceversawill run-off theexistinglayer or will be displaced by the subsequent layer. The stability of the system depends on the rheology anddewateringpropertiesofeachlayer.TheconsolidationbehaviouroftheinterlayereddepositwasthenmodelledusingSOILVISIONandFSConsolsoftware.TheconsolidationmodelshowedthatthereisnosignificantdifferencebetweenthemixedTT-flocculatedFFTandtheinterlayeredTT-flocculatedFFT.

Afterobtainingthemodellingresults,theexperimentalworkwasdesigned.Thefirstroundoflaboratorytestswasdesigned to understand the flocculation performance of FFT using a single stage flocculation (at the secondchemical injection at point). FFT with a range of solids content from the fluid tailings deposit area, the westexternaltailingsarea(WETA),wastestedandthemixingandflocculantdosagewasoptimized.

Afterthisstage,thelaboratoryco-depositiontestmatrixwasdesigned.Themainscenariostestedwere:

• depositingon-specandoff-specflocculatedFFTontoTTtounderstandtherun-offbehaviour;and• depositingTTontoflocculatedFFTtounderstandthedisplacementofFFTbyTTovertime(between30

minutesto24hours)andvaryingsolidscontentandyieldstress.

Allthetestswereconductedinflumesofthesamesize(20mby100m).

After the laboratory testing, interlayered TT samples with flocculated FFT and mixed TT-flocculated FFT wereprepared for consolidation behaviour tests using the beam centrifuge at the University of Alberta (U of A) toconfirmtheconsolidationmodellingresultswithactualtailingssamples.

TheimportanceofthisprojectforKearl istotreatFFTevenwhenthethickenerisnotrunninganddecouplethesecondflocculant(chemical)injectionpointfromupstreamoperation.Basedontheconsolidationmodelling,andsomelimitedlabstudiesusingbeamcentrifuges,theperformanceoftheTTmaterialwithinterlayeredflocculatedFFT compare to TT deposit was not significantly different. With the field trial, there would be betterunderstanding of the behaviour of TTwith interlayer flocculated FFT performance to evaluate the reclamationactivities.

Theplanforthefieldtrialincludes:

• Phase1–depositionofflocculatedFFTtotheeastoftheTTpanelsinthecurrentTTdepositarea;and• Phase2–depositionofflocculatedFFTwithintheTTpanels.

ThecurrentregulatorypilotauthorizationisforthedepositionofalimitedvolumeofflocculatedFFTtotheeastofTT panels until the end of 2019. Future phases are being planned and will be subject to additional pilotauthorizationsforthesephasesfromtheAER.

Indesigningthisproject,previousworkatotheroilsandsfacilitiesusingin-lineflocculationofmaturefinetailings(MFT),aswellasoptimizingthemixinganddosageofthepolymerwiththeMFT,wasexamined. Theupcomingfieldtrialwillcontributetothegrowingbodyofknowledgeforimprovingoilsandstailingsmanagement.



Results from the co-deposition and consolidationmodelling studywerepromising—supporting the feasibility ofco-depositing flocculated FFT and thickened tailings. Modelling showed that flocculation of FFT using a singleflocculantwassuccessfulatahigherflocculantdosage.Modellingalsoindicatedthatasolidscontentof20%(wt)(i.e.,differentthantheinitialsolidscontentoftheFFT)resultedinimproveddewateringandconsolidation.

The beam centrifuge results demonstrated that interlayering flocculated FFT and TT does not change theperformance of the TT consolidation in a one-dimensional (1D) cell, confirming the modelling results fromSOILVISIONandFSconsol.

Co-deposition of flocculated FFT and thickened tailings in the laboratory scale flume showed that for on-specflocculatedFFT,thematerialwillstayinplaceandwillnotrunontopofthedepositedTT.ThelaboratorytestalsodemonstratedthesuccessofdepositingTTonflocculatedFFT.Forexample,theFFTlayerwasnotdisplacedafteracertain lengthoftimefollowingdeposition, indicatingthattheFFThadgainedenoughstrengthandreachedacertainsolidscontent.

The efforts to date support the concept that co-deposition of TT and flocculated FFT is feasible under certainoperationalanddepositconditions.Thenextstepwilltesttheconceptatacommercialfieldscale.

LESSONSLEARNED

The study proved the feasibility of additional FFT treatment using in-line flocculation and co-deposition undercertainconditionswithTTwithoutimpactingthelong-termperformanceofTT. TheconceptwillbestudiedatalargerscaleduringthetrialatKearl.



Zambrano,G.,Wang,Y.,Chalaturnyk,R.,Zahabi,A.,Rennard,D.2018.AssessmentofSelf-weightConsolidationofCo-deposition Deposits in the Geotechnical Beam Centrifuge. Presented at IOSTC 2018. Sixth International OilSandsTailingsConference2018.Edmonton,Alberta.December9-12,2018.




DegreeorJobTitle

DegreeStartDate

(ForStudentsOnly)


(ForStudentsOnly)

AtoosaZahabi Imperial ResearchScientist YijunLiu Imperial ResearchScientist GivemoreSakuhuni ExxonMobil ResearchScientist DaveRennard ExxonMobil ResearchScientist PaulCavanagh Imperial SeniorTechnicalAdvisor

ResearchCollaborators:GeotechnicalCentrifugeExperimentalResearchFacility(GeoCERF),UniversityofAlberta


AcceleratedDewatering/RimDitchingCOSIAProjectNumber:TJ0109



Status:Ongoing

PROJECTSUMMARY

Accelerateddewatering(ADW)orrimditchingisatailingstreatmentprocessthatinvolvesthemixingofachemicalamendmentwith fluid fine tailings (FFT) followed by careful control of the deposit surfacewater. The surfacewateriscontrolledbycreatingperimeterandlateralditchesaroundtheedgesandonthesurfaceofthedeposit,respectively.Thelateralditchesdirectsurfacewatertowardsadecantstructurefromwherethewaterisremoved.Todate,threesetsofpilotdepositshavebeencreated,eachusingdifferentchemicalamendments.Thefirstwasapolymertreatmentonly. Itwasdepositedin2009andhasbeenmonitoredsince.Mixingwasnotoptimizedforthis firstpilotdepositand it isestimated thatonlyabout80%of thedepositwas ideallymixed. A secondpilotdepositin2017employedstateoftheartmixingtechnologyaswellasagypsumpre-treatmentoftheFFTpriortopolymeraddition. Monitoringof the flocculatedFFTduringthecell fill suggestedthat100%of thisdepositwasideally mixed. A third pilot deposit was filled with ideally mixed and hydrophobic flocculated FFT. This thirddepositwascreatedfromaprocessthatproducestheideally-flocculatedFFT,andthentreatstheresultingflocstomakethemhydrophobic. Thishydrophobic flocculatedFFTcouldpotentiallyhavean improveddewatering ratebecauseof thegreaterhydraulicconductivity.Eachof thesepilotdepositswasapproximately10mdeepwithavolume of 60,000-70,000 m3. Long-term dewatering and consolidation trajectories for the pilot deposits aretrackedthroughinsitumonitoring,testingandsampling.


Several years ofmonitoring data are available for the initial ADWdeposit created in 2009, and themonitoringprogramhasonly justbegun for themore recent2017deposits. For the2017pilotdeposits, thecell floorwasslopedandthedecantstructurewasplacedatthelowestelevationinordertomakerimditchingandcontrolofsurfacewatermoreefficientcompared to the2009pilotdeposit. Experiencewasgained inunderstanding themixing operating window as feed FFT fines content changed during the deposition, as well as the relationshipbetweenmixingefficiencyandsolidscontent.Densitycontrolwasusedduringthefill,sotheonlymixingvariablewas the fines content in the FFT. At approximately 30% FFT feed solids, the operation required minimalmonitoringtoensureconsistently“ideal”mixing.Controlofthedepositreleasewaterwaseasierthaninthe2009testprogrambecausetheidealmixingin2017createdamoresignificantdepositsloperesultinginadeeperandeasiertopumpwatercapatthefarendofthedeposit. Monitoringandrimditchingtominimizeandeliminatesurfacewaterwillcontinueandcomparisontothe2009depositperformancewillcontinueforseveralyears.


LESSONSLEARNED

The dynamic in-linemixers used in the 2017 pilot programwere reliable,with little operating downtime. Thisobviated the need for extraordinary process monitoring and control. The flocculated FFT maintained itsdewateringpotentialoversignificantpipeliningdistancesfromthemixingpoint (inexcessof700m),supportingprevious work that suggested floc integrity could bemaintained under laminar flow conditions. The physicalconfigurationofthefieldpilotdidnotallowfortestingpipelinedistanceswhereflocdegradationmightoccur.Thedynamicin-linemixersdesignedbySyncrudeCanadaLtd.wereeffectiveatflowratesinexcessof600m3/h,buthydrauliclimitationspreventedconfirmationofhigherrates.Itisnotablethat600m3/honlyrequired50to60%of the maximum mixer speed; indicating significantly higher throughputs should be possible. Controlling thechemicalsandmixingregimestoallowforhydrophobictreatmentof theflocculatedFFTwaschallengingduetothemultiplecomponentsandelevatedtemperaturesrequiredforthetreatmentreagents.Protocolsandeffectiveprocess control strategieswere developed to achieve flocculation and hydrophobic treatment on a continuousbasis.TheexpertiseisnowavailableatSyncrudeCanadaLtd.tocreatetheselargedeposits,onaroutinebasis,ifrequired.



PrincipalInvestigator:BarryBara


DegreeorJobTitle

DegreeStartDate

(ForStudentsOnly)


(ForStudentsOnly)

JimLorentz SyncrudeCanadaLtd. TeamLeader EricLeneve SyncrudeCanadaLtd. SeniorAssociate BarryBara SyncrudeCanadaLtd. SeniorAssociate-Mechanical SimonYuan SyncrudeCanadaLtd. SeniorAssociate-Chemical RonSiman SyncrudeCanadaLtd. SeniorTechnologist ChrisSchroeter SyncrudeCanadaLtd. SeniorTechnologist RandyMikula KaliumResearch Consultant


MixingCoarseTailingsintoInsituFineTailings:LiteratureandOperationalCaseStudyReviewCOSIAProjectNumber:TJ0111

ResearchProvider:BarrEngineeringandEnvironmentalScienceCanadaLtd.



Status:Completed

PROJECTSUMMARY

Mixingonetypeoftailingssuchasfinetailingswithadifferenttypesuchascoarsersandtailingsmight improvethestrengthandconsolidationratewithinthetailingsdeposit. Themechanismsorphysicalprocessesbywhichfinetailingsarecapturedoradmixedwith insitu tailingspreviouslydeposited inthetailingsbasinare,however,notwellunderstood.

Theoverarchingpurposeof the studywas to assesswhether fines (fine tailings) capturemightbe the result ofsubaqueous(belowthewatersurface)gravityflowsoftailings—turbiditycurrents,debris flows,orgrainflows—transportingsandfinestothedeepersectionsofbasinsandgeneratingadmixturesofsandandfines.

Thestudyreviewed literaturefromnaturalsystems(erosionofsediments intomarineenvironmentsandrivers),reservoirscreatedfromdammingrivers,andminetailingsbasins,includingoilsandsmines.

Apathforwardandrecommendedtechnologydevelopmentstepsareoutlinedinthestudy.


Progressandachievementsarehighlightedinthesection,LessonsLearned.

LESSONSLEARNED

Allof thecasestudiesreviewed indicatethatmixingsand intopre-existing finetailingsto improvethedeposit’sreclamation characteristics is possible. Questions remain, however, about the viability of sand mixing at anoperational-scale at oil sands operations. Several of the non-oil sands mine examples show how operatorsmanipulate tailings streamcharacteristics tooptimize turbidity currentbehaviour. Similar approaches couldbeused in oil sands operations to promote turbidity current formation, and delivery of sand from the beach todeeperportionsof thebasins. However, enough insight from theoil sands studiesdidnotdeterminewhetherturbiditycurrentsandmixingcouldleadtoreclamation-readydeposits.


Tominimizetheriskassociatedwithfuturefieldorcommercialstudies, theviabilityof thesandmixingmustbedetermined.Recommendedtechnologydevelopmentsteps;i.e.,additionalstudiesarerecommendedfor:

1. thedevelopmentofsandmixingtheoryandnumericalmodelling;2. re-analysisofexistingandongoingoilsandslaboratoryandfielddatasets;and3. laboratory-scaleexperimentstovalidatetheoriesdevelopedwhileconductingstudiesforitems1and

2.


Institution:Imperial

PrincipalInvestigator:AtoosaZahabi


orJobTitle

DegreeStartDate

(ForStudentsOnly)


(ForStudentsOnly)

AtoosaZahabi Imperial

BenSheetsBarrEngineeringandEnvironmentalScienceCanadaLtd.


GeobagsPilotStudyCOSIAProjectNumber:TJ0112

ResearchProvider:CanadianNaturalResourcesLimited



Status:Completedin2018

PROJECTSUMMARY

Intheoilsandsindustry,thereareopportunitiestoincorporateFFTintoadry,terrestriallandform.Geobagsareatechnologyfortreatingfluidfinetailings(FFT),whereadrylandscapeisrequired.Geobagsaresimplylargebags(upwardsof100mlongand40mcircumference)madeofapermeablegeotextile.FFTistreatedwithachemicalamendmentsuchasapolymeroralum,andthenpumpedintothebag.Waterisreleasedthroughtheporesofthebag, leavingadenser,strongermaterialcontainedwithinthebag. The intent istostackthebagsontopofoneanother;creatingalandscapecompatiblewithmineclosureplans.TheultimateheighttowhichthebagscanbestackeddependsonthestrengthachievedbytheFFT.

Thegoalofthepilotwastocollectallofthenecessaryinformationtocreateacommercialdesignforevaluationandcomparisonagainstothertechnologies.FFTwasdrawnfromanexistingtransferlinefromtheMuskegRivermine(MRM)externaltailingsfacility(ETF)andstoredinaholdingpondwith10,000m3ofstorage. TheFFTwaspumped fromthepond througha systemwhere itwasamendedwithchemicalamendmentsandexposed toavarietyofshearregimespriortoflowingintothebags. Fourdifferentchemicalamendmentsweretested.Asitewaspreparedthatenableddrainagewhilemaximizingtheuseofthebagvolume.Bagsofdifferentsizeswereusedto test the effects of scaling. Bags were stacked one on top of the other. Run-off water from the bags wascollectedforanalysis.Muchattentionwaspaidtooperationalissuesaswell.Safetyandefficiencywereprincipaloperational considerations for the pilot study. Lessons learned from the pilot studywill be valuable for futurecommercialevaluationofthetechnology.

As a result of the pilot study, treating FFT at a commercial scale, through the use of geobags and chemicalamendments,isconsideredviable.GeobagstechnologyprovidesanothertoolavailablefortheoilsandsindustrywhenincorporatingFFTintheterrestrialclosurelandscape.


Thetestprogramranthroughoutthesummerandfallof2018.Thefollowingkeyobjectivesweremet:

• 11geobagswerefilled.Fourwere“recipe”geobagstestingdifferentchemicalamendments;fourwere“stacking”geobags,oneontopoftheother;threewere“scaling”geobags.Thethreescalinggeobagswereofvaryingsize,rangingfromonefullscalecommercialgeobag(100mlengthby40m


circumference),onemediumscalegeobag(30mlengthby27mcircumference),andonesmallscalegeobag(30mlengthby18mcircumference);

• recipestested includedcommerciallyavailablepolymers (flocculants)andalum. Thepolymers includedDowXUR,SNF3338,andBASF1047.TherecipesincludedDowXUR,SNF3338polymerandalum(threedosagesweretested),andBASF1047andalum.Mixing/shearwasvariedaswell;and

• operationallessonslearnedwillinformthedesignforaviablecommercialoperation.

The bags will continue to dewater over time. The impact of freeze-thawwill be of particular interest. Solidscontentandstrengthwillbemonitoredthroughuntilthesummerof2019.Finalconclusionsontheperformanceofthepilotstudywillbesummarizedinafinalreport.

Itisanticipatedthatextrapolationofthepilotstudy’sresultswillenablepredictionofsolidscontentandstrengthforacommercialoperation. It isalsoexpectedthatthenumberofbagsrequiredforagivenamountofFFTandtheultimateheighttowhichthebagsmaybestackedcanbedetermined. Furtheroptimizationofthechemicalamendment at an operating scale may be possible. From there, a plan to incorporate geobags into a finallandformcanbeformulated.

LESSONSLEARNED

As a result of the pilot study, treating FFT at a commercial scale, through the use of geobags and chemicalamendments, is viable. Geobags are another tool in the tailings treatment toolkit for incorporating FFT in theterrestrialclosurelandscape.


Institution:CanadianNatural,Chevron

PrincipalInvestigator:JasonHill

ResearchCollaborators:TeckResourcesLimited


PressureFiltrationforFluidFineTailingsTreatmentCOSIAProjectNumber:TJ0113




Status:Labscalepilotcomplete;commercialpilotongoing

PROJECTSUMMARY

The filterpress isawell-knowntechnology that improveswater recoverybymechanicallypressingwateroutoffineclaymaterialstoformadenseclay-likecakesuitablefortransporttoareclamationarea.Eventualcloggingoffilter materials by fines (solid particles less than 44 microns) and residual bitumen has, however, preventedadoption of the technology for treating fluid fine tailings (FFT). The added step of chemically treating the FFTbeforemechanicalfiltrationresultedinpromisingresultsatalaboratoryscale.Thisprojectisacommercialscaledemonstrationstudythatbuildsonthesuccessofthepreviouslaboratoryscaleresults.Thegoal istodeliver inexcessof70%solidsbyweightinthepressedproduct(cake).Thepurposeofthecurrentprojectistodeliveralloftheinformationrequiredtodesignacommercialplantandtoevaluatethetechnologywithalternativetreatmenttechnologies.

Laboratory scale presses and a pilot scale press operated by Ledcor Nalcowere used during the first phase oftesting to identify importantparameterssuchasoperatingpressureandwhichchemicalamendmentsaremoreeffective. Thecommercialscaledemonstrationplantwillbedeployed inthefield,with live feedcomingfromaFFT harvesting operation. This demonstration plant will consist of a feed conditioning system and two filterpressesof differentdesign. Engineering for the commercial scaledemonstrationplantwas completed in2018.Construction commenced in 2018 andwill continue through the spring of 2019. The demonstration plantwilloperatethroughthesummerof2019withresultsavailablelatein2019.

It is expected that the commercial scaledemonstrationplantwill deliver the following information for a futurecommercialoperationsdesign:

• requiredoperatingpressure;• cycletime;• needforbladdersqueeze;• needforlowshearpumps;• requirementfordecantersonthefeed;• economicalchemicalamendmentstrategy;and• filterpressproductanddischargemanagementsystem.



The laboratoryscaleprograms, includingtheLedcorNalcopilot,haveprovidedresults that informthe followingdecisionsondesignparametersforthecommercialdemonstrationtobetaken:

• operatingpressurerange,700kPato2100kPa;• incorporationofbothabasicpressandonewithanadditionalbladdersqueezeoption;• twostageamendmenttreatment,coagulantandflocculant;• differentfeedpumpoptionswithdifferentshearprofiles(shearingofthetreatedFFTwasidentifiedasa

keyoperatingparameter).

Based on the results achieved during the laboratory-scale study, filter presses appear to be a competitivetechnology for producing a sufficiently dense product fromFFT that is suitable for rapid terrestrial reclamation(andcreatingadrylandform).

LESSONSLEARNED

Solids contentofmore than70%byweightwasachievedat reasonable cycle timesduring the laboratory scalepilotstudy. Ifsimilarresultsareachievedwiththecommercialscaledemonstrationandplantreliability isgood,thechemicaltreatmentsofFFTfollowedbymechanicalfiltrationprovidesanothercompetitivetoolinthesuiteofFFTtreatmenttechnologies.



PrincipalInvestigators:GavinFreeman,CynthiaCote

ResearchCollaborators:TeckResourcesLimited,LedcorNalcoServices(laboratoryscalepilot)


ManagingTailingsfromtheCreatingValuefromWasteProcessCOSIAProjectNumber:TJ0114

ResearchProvider:CanadianNaturalResourcesLimited(CanadianNatural)


IndustryCollaborators:TitaniumCorporationInc.,ThurberEngineeringLtd.,SNFMining

Status:Year1of2

PROJECTSUMMARY

Titanium Corporation Inc. has developed a process called Creating Value from Waste (CVWTM) that recovershydrocarbonsandvaluablemineralsfromfrothtreatmenttailingsandisbeingconsideredforimplementationatCanadian Natural’s Horizon site. The process creates a tailings stream with characteristics different fromtraditionalfrothtreatmenttailings,openingopportunitiesastohowtomanagethesetailingsoncethebulkofthehydrocarbon is removed. For example, they are easier to densify and the methanogenesis (the formation ofmethanebymicrobesunderanaerobicconditions)potentialisgreatlyreduced.

TheCVWTMtailingsstreamhasnotbeenhandledpreviouslyonacommercialscale.Thefocusofthisprojectistocollecttheengineeringdatarequiredtooptimizetheprocessinganddepositionofthisnewtailingsstream.

Modeltailingsstreamswerecreatedthatspannedtherangefromcurrentnaphtharecoveryunit(NRU)tailingstoclean(allhydrocarbonsremoved)tailings.Thetailingswerethickenedinalaboratoryscaledynamicthickenerandthenecessary data collected to size anddesign a commercial scale thickener, associatedpumps, andpipelines.Samplesof the tailingsarecurrentlyundergoing testing in largestrainconsolidation (LSC)cells. Thesetestswillprovidetheinformationrequiredtodevelopadepositionandreclamationstrategy.

Assuming a positive result from this work and an engineering study on the CVWTM process, this work will beincorporatedintofuturetailingsmanagementplans.


Threetypesofmodeltailingswereprepared,spanningtherangethatcouldpotentiallybeseenfromtheCVWTMprocess. Thickeningtestswerecompleted in2018. Theresults fromthetestingwereusedtosizeanddesignahighratethickenerandestablishflocculanttypeanddosagerequiredtoachieveproperthickening.Itwasfoundthatthematerialcouldbethickenedupto>55%solidsbyweight. Rheologytestswerealsocompletedonthethickened tailings. These tests revealed that the shear stress increases dramatically beyond ~50 % solids byweight,makingsuchadensestreamimpracticaltopumpwithacentrifugalpump.


Theaboveinformationwassufficientforsizingathickenerandpumpingsystem,aspartofthelargerengineeringstudyoftheCVWTMprocess.

AtotaloffiveLSCtests,includingsedimentationandindextesting,wereinitiatedin2018.TheLSCtestresultswillbeavailablein2019andwillbeincorporatedintothetailingsmanagementplanforCVWTMtailings.

LESSONSLEARNED

Once the program is complete, enough data will have been collected to design a system for handling CVWTMtailings. The outcomes will also help inform the deposition strategy for this stream. The economics of themanagementstrategyforthisspecifictailingsstreamaresitespecificandmustbeconsideredwithintheoverallcontextoftheoperator’stailingsmanagementplan.



PrincipalInvestigator:DanutaSztukowski


orJobTitle

DegreeStartDate

(ForStudentsOnly)


(ForStudentsOnly)

DanutaSztukowskiCanadianNaturalResourcesLimited

ProcessEngineer,ProcessInnovation

PeterStapletonCanadianNaturalResourcesLimited

LeadEngineer,ProcessInnovation

KevinMoran TitaniumCorporationInc.VicePresident,Technology

NielErasmus TitaniumCorporationInc.VicePresident,MineralSands

SaidulAlam ThurberEngineeringLtd. TailingsEngineer SilawatJeeravipoolvam ThurberEngineeringLtd. GeotechnicalEngineer

MarkNiederhauser SNFMiningDirector,MiningApplications


FROTHTREATMENTTAILINGS


FrothTreatmentTailingsEvaluationCOSIAProjectNumber:TE0050andTJ0110

ResearchProvider:GolderAssociatesLtd.,InnotechAlberta

IndustryChampion:Imperial,SuncorEnergyInc.

IndustryCollaborators:CanadianNaturalResourcesLimited,SyncrudeCanadaLtd.,TeckResourcesLimited

Status:Year2of4

PROJECTSUMMARY

Froth Treatment Tailings (FTT) is the smaller of two tailings streams that form during bitumen extraction frommineable oil sands. In the froth treatment process step, bitumen froth from the primary extraction process iscontacted with a light hydrocarbon mixture (naphthenic or paraffinic in nature, depending on the oil sandsoperation)tofacilitateseparationofsolidsandwaterfromthebitumenphase. Thewaterandsolids,combinedwithsomeunrecoveredbitumenandtracelighthydrocarbonreporttotailingscontainmentareasforstorageandwaterrecovery.

The FTT composition is unique due to its elevated concentrations in oleophilic (oil-liking) minerals thatpreferentiallyassociatewiththebitumenfrothinprimaryextraction.Someofthesemineralsareknownacidrockdrainage(ARD)precursors(e.g.,pyrite),andcancontainnaturallyoccurringradioactiveminerals(NORM).Further,thetracelighthydrocarbonsfromthefrothtreatmentcircuitareknowntosupportmicrobialactivityinthetailingscontainmentareas.Inordertomanageshort-termoperationalrequirementsaswellaslong-termclosureneeds,amoredetailedunderstandingofthebio-geochemicalbehaviourofthisstreamwasdesired.

TheFrothTreatmentTailingsEvaluationprojectwas initiated in2017tocloseknowledgegapsaroundthe long-termenvironmentalbehaviourofFTTdeposits.Theprojectkickedoffwithanindustry-widesamplingcampaignin2017.Theprogramwasaimedatcomparingandcontrastingthedepositcompositionofmaterialsofdifferentage,depositionenvironmentandlighthydrocarbontype.Specifically,gas,aqueous,hydrocarbonandsolidschemistrywere analysed, and the microbiology present in the deposits was characterized. The initial intent was todetermine insitubio-degradationratesofresidual lighthydrocarbons. Theprogramhassinceexpandedtohelpassess ARD/NORM related effects as well. Deeper fundamental insight of the deposit behaviour can informclosureplansfortheindividualoperatorsinfuture,andserveasastartingpointfordedicatedmitigationoptionsifrequired. A follow-upcampaignwasexecuted in2018 for severaloperators inanattempt todetermine in situkineticinformation.Analysisofthegenerateddatasetsiscurrentlyunderway.


ResultsfromthefirstsamplingcampaignhaverevealedanumberofnewinsightsinthedynamicsofFTTdeposits,initialresultsofwhichwerepresentedatthe2018OilSandsInnovationSummit(OSIS).Highlightsincluded:


• Evidence of entrapped gas in some deposits. This suggests that bio-gas generation rates are notnecessarilyequaltobio-gasreleaserates.

• Higher than expected variability within the deposits (both laterally and vertically), as well as betweenoperations. This emphasizes that FTT management will likely have a site-specific component, andoperationalhistoryofthedepositsmayplayasignificantroleintheobservedbehaviourofthedeposits.

• Significantly enhanced insights in diversity and abundance of microbial activity within the variousdeposits. A core micro-biome is present within all tailings facilities, capable of light hydrocarbondegradationamongstotherfunctions.

Workisongoingtofurtherinterpretthedata.Thefocusiscurrentlyonextractinginsitukineticrelationsfromtheinformation, to enable predictions of long-term deposit behaviour. In addition, attempts aremade to identifyrate-limiting (micro-)nutrients in the deposits. This could provide a means to steer microbial activity towardsdesiredendstates.

LESSONSLEARNED

Thisprogramisinitsearlystagesthereforeresultsaretoopreliminarytobepresentedaslessonslearned.



InnovationSummit2018,June7-8,2018,HyattRegency,Calgary,Alberta:

• S.Fawcett,“Region-WideFrothTreatmentTailingsDepositSampling”

• K.BudwillandJ.Birks,“RegionalAssessmentofDiluentDegradationinTailings:PreliminaryInsightsfromMicrobiologyandHydrocarbonAnalyses”

• S.Fawcett“DevelopmentofanAnalyticalProgramandData InterpretationApproachforAssessingAcidRockDrainageRisksinOilSandsTailings”

• S.Fawcett“FirstLookatInsituGasConcentrationsMeasuredinFrothTreatmentTailingsPonds”




DegreeorJobTitle

DegreeStartDate

(ForStudentsOnly)


(ForStudentsOnly)

SkyaFawcett GolderAssociatesLtdAssociate,SeniorGeochemist

JeanBirks InnoTechAlbertaPrincipalResearcher,WaterResearch

KarenBudwill InnoTechAlbertaSeniorResearcher,ProcessingTechnologies


MinimizationofGreenhouseGasEmissionsinFrothTreatmentTailingsbyManipulationofElectronAcceptorsCOSIAProjectNumber:TE0055,RWG(IOSI18)

ResearchProvider:Queen’sUniversity


IndustryCollaborators:CanadianNaturalResourcesLimited,Imperial,SyncrudeCanadaLtd.,TeckResourcesLimited

Status:Year1of3

PROJECTSUMMARY

The main sources of carbon dioxide (CO2) and methane (CH4) emissions in tailings ponds are from thebiodegradationofdiluent(naphthenicorparaffinicsolvents)usedinfrothtreatment,andtoalesserextent,fromresidualbitumen. However,differenttypesoftailingscanbemixedinthesametailingpondsandcaninfluencethe composition of the microbial community involved in degradation. Differences in diluent composition anddepositionpracticesmake itdifficult toextrapolatetherelationshipbetweenmicrobialactivityandCO2andCH4emissions fromone tailingspond toanother. CH4hasaglobalwarmingpotential (GWP)of28-36 times thatofCO2, therefore reducingor eliminatingCH4 emissions canbeof significant environmental andeconomicbenefitunderAlberta’sClimateChangeStrategyandmustbeaddressed.Intheponds,CH4productionisduetothebio-oxidationofhydrocarbonscoupledtothereductionofterminalelectronacceptors(TEA)suchasaceticacidorCO2atlowredoxconditions(~-250mV)whenotherTEAareabsent.WhenotherTEAarepresent,theredoxpotentialincreasesandmethanogenesisisinhibited.

Thekeyresearchobjectives/milestonesofthisprogramareto:

1. EvaluatetheimpactoftheconcentrationofdifferentTEA(suchassulphateandnitrate),ofdiluent(e.g.,naphtha) andof nutrients such as phosphate and ammoniumonbiogenic gas production from tailingsobtainedfromdifferenttypesoftailingponds(impactedbyfrothtreatmenttailings)atdifferentdepthsand lateral locations on the rates of biogenic gas production, consumption of TEA, and hydrocarbondegradationinlaboratorymicrocosmstudies.

2. Evaluate the effect of bitumen aggregates on biodegradation rates in static microcosm studies andwhether residual solvent trapped inside bitumen aggregates offer amass transfer resistance thatmaylimitbiodegradationrates.


3. Developafirstgenerationmodelcouplingmasstransferandreactionratestoprovidebasicinformationon CO2 and CH4 emissions based on pond chemistry, and to use the model to potentially identifydominantmechanismswhichmayaidindevelopingstrategiesforminimizingCH4emissionsinsituorformanipulatingthebiodegradationrateofthediluent(naphtha).


Objective1–EffectofTEA,phosphate,ammoniumetc.onGreenhouseGasproduction:

Since the start of the project, we have put many protocols in place for our experimental setup and for theanalytical techniques to monitor greenhouse gas (GHG) production and naphtha degradation. In June, wereviewedwithSuncorEnergyInc.(Suncor)thewaterchemistryofrelevanttailingpondsand,basedonthesedata,itwasdecidedthatmaturefinetailings(MFT)samplesshouldbetakenfromtwoseparateSuncortailingsponds.ThesesamplesarrivedatourlabinAugust2018andwehavebegunsettingupstaticmicrocosmexperimentstoaddressObjective1.ForeachTEA,aninitialseriesoffactorialdesignexperimentsbasedonthreefactors(theTEA,naphthaand theN:P [ammoniumphosphate] ratio)at twoor threeconcentrationsofeachof the three factorsweresetuptohelpidentifythemostimportantfactorsaffectingGHGproductionandnaphthadegradationrates.Theseresultswillalsobeusefulinrefiningtheconcentrationrangesthatshouldbestudied.

Resultsfrompreliminaryexperiments,withaMFTsampleprovidedbySuncorsuggestthatphosphate(PO43-)was

one of the key nutrients limiting degradation rates. This is consistent with high performance liquidchromatographyHPLC/ Ionchromatographyanalysisof theporewaterof the twotailingsponds,bothofwhichwerebelowdetectablelevels(PO4

3-<1.0mg/L).

Objective2–Effectofbitumenonnaphthabiodegradation:

In developing an appropriate protocol to meet this objective, initial sacrificial experiments in triplicate arecurrentlybeingsetupunderabioticconditionsinwhichaknownamountofbitumencontainingaknownamountof naphtha is added to a series of vials containing simulated porewater. Over time, vialswill be sacrificed tomeasurenaphthacomponentsintheaqueousandbitumenphase.Oncethismethodologyisestablished,similarbioticexperimentswillbeperformedinwhichanaphtha-degradingcultureenrichedfromMFTwillbeadded.

Objective3–Firstgenerationmodel:

Development has begun on a numerical model to address Objective 3. An existing model that accounts fordiffusion within an oil mixture and mass transfer at the oil-water interface has been modified to includedegradationinthewaterphase.Preliminarysimulationshavebeenconductedtoinvestigatethesensitivityoflighthydrocarbon(benzene,xylene,ethylbenzene)releasefromamixedoildroptodropsize,oilmixtureviscosity,anddegradationrateinthewaterphase.

LESSONSLEARNED

Thisprogramisinitsearlystagesthereforeresultsaretoopreliminarytobepresentedaslessonslearned.



Institution:Queen’sUniversity

PrincipalInvestigator:JulianaRamsay


orJobTitle

DegreeStartDate

(ForStudentsOnly)


(ForStudentsOnly)

KevinMumford Queen’sUniversityCo-PrincipalInvestigator

BruceRamsay Queen’sUniversityCo-PrincipalInvestigator

DebajyotiGhosal Queen’sUniversity PostdoctoralFellow

SaeidShafieiyoun Queen’sUniversityPostdoctoralFellow(part-time)

SreemoyeeGhoshRay Queen’sUniversityPostdoctoralFellow(part-time)

MickelTawadrous Queen’sUniversity MScCandidate September2017 August2019AveryLing Queen’sUniversity BScstudent AlisonHolman Queen’sUniversity BScstudent


CONSOLIDATIONMODELLING


NSERC/COSIAIndustrialChairinOilSandsTailingsGeotechniqueCOSIAProjectNumber:TE0010

ResearchProvider:UniversityofAlberta



Status:Year4of5

PROJECTSUMMARY

In 2013, the COSIA Tailings Environmental Priority Area (EPA) and the University of Alberta joined forces toestablish the NSERC/COSIA Industrial Research Chair in Oil Sands Tailings Geotechnique (IRC) to address thechallenges ofmanagingoil sands tailings and remediating tailings pond sites. Upon consultationwith industry,fourmajorareasofinnovativeresearchweredeterminedfortheIRCprogramasfollows:

1) investigatingtheunsaturatedsoilmechanicalpropertiesofoilsandstailings;2) investigating consolidation processes for various forms of fluid fine tailings (FFT), mature fine tailings

(MFT)andamendedMFT;3) assessingandimprovingtailingsdeposition;and4) understanding the long-term geotechnical behaviour of fine tailings through laboratory testing and

simulations.

ThroughtheIRCprogram,18highlyqualifiedpersonnel(HQP)havebeentrainedtoconductresearchunderthesefourIRCthemeswithindividualprojectobjectivesprimarilyaimedatassistingtheindustrytoachievethemandateof Alberta Energy Regulator (AER) Directive 0741. While the industry made progress under Directive 074,experience demonstrated that further advanceswere needed. A newDirective issuedby theAER in 2016 andupdatedin2017,Directive085,specifiesthatnewFFTdepositsmustbereadytoreclaimtenyearsaftertheendofmine life, and that all legacy2 tailingsmust be ready to reclaim by the end ofmine life. Thus, adjustments toindividualprojectswithinthefourIRCthemesweremadetoaccommodatetheshiftinresearchpriorities.

Thecollaborativeresearchisresultinginthedevelopmentofnewfieldinvestigationtechniques,tailingssimulationmodels and unsaturated soil mechanical models, which have been transferred to Canada’s oil sands tailingsindustry.Severalofthefieldinvestigationsarebeingcarriedoutincollaborationwiththeindustrysponsors.Thus,the results are directly being developedwith and transferred directly to the sector users. Also, theHQP have

1Directive074:TailingsPerformanceCriteriaandRequirementsforOilSandsMiningSchemeswasrescindedin2016andreplacedbyDirective085:FluidTailingsManagementforOilSandsMiningProjects2legacytailingsaredefinedinDirective085asfluidtailingsinstoragebeforeJanuary1,2015.


presented their findings at conferences, such as the International Oil Sands Tailings Conference or COSIAInnovationSummit,disseminatingtheirworktothewideroilsandscommunity.Additionally,in-personmeetingswith the Industrial Research Chair Research Advisory Committee provide industry with opportunities to learnaboutthe IRCresearchprogress,toprovidefeedbacktotheresearchteamtoensurethe industrialrelevancyoftheworkandtoengageinfurtherdiscussionsbetweentheirorganizationsandtheHQPtoadvancetheresearchprojects. The collaborationbetween theCOSIATailingsEPAand theUniversityofAlbertaenables fundamentaldiscoveries for the behaviour and improved management of fluid fine tailings, benefitting the engineeringdiscipline,miningreclamationandoilsandstailingsgeotechnique.


The current IRC program is providing COSIAmemberswith novel technologies tomeasure the effectiveness ofcurrent tailings remediation efforts, new and innovative processes for reducing the amount of post-productiontailings, understanding the long-term geotechnical behaviour of fluid fine tailings, aswell as tailings simulationmodels to assist industry with tailings planning and management. These novel approaches to the industrialresearchchallengeshaveincreasedtheresearchcapacitiesofboththeUniversityofAlbertaandindustrypartners.

Forexample,waterseparationandremoval fromsaturatedtailings (e.g.,mature fine tailings) is the first step indensifyingandconsolidatingtailings.OneofthecompletedprojectsfromtheIRCdevelopedempiricalcorrelationsbetweentotalsuctionandhyperspectralimageryforthinsectiondryingtestsforarangeoffluidfinetailings.ThePhD student (who graduated in 2016 and is currently working in industry to operationalize the technologydevelopedduringhisPhDprogram for tailings characterization) investigated the remoteestimationofmoisturecontent,evaporationrateandtotalsuctiontohelpoilsandsoperatorsassessthedryingprocess,determinewhenthedeposithasstoppeddryinganddecidewhenthenext liftshouldbedeposited. Ourworkprovided low-risk,cost-effectivequicksurveystothetailingsoperatorstomanagetheirlargevolumeoftailings,andthus,facilitatedtheaccelerationoftheconversionprocessoftailingstoreclaimablelandscapes.

Inanotherexample,apostdoctoralfellowworkedoncouplingfreeze-thawanddesiccationdewateringcodesintoonecommonmodellingplatformusingMATLAB.Thisprojectiscompleteanddevelopedacomputerprogramtosimulate the dewatering of thickened tailings using natural processes, including freeze-thaw, consolidation anddesiccation,whicharerelevanttotheoilsandsindustryintheFortMcMurrayregion.Thecodedevelopedbythepostdoctoral fellow under the IRC program, Freeze-Thaw-Consolidation-Desiccation (FTCD), is currently beingtrialedinindustry.In2014,thepostdoctoralfellowwashiredbyindustryasaresultofthisnumericalmodellingworkintheIRCprogram.

The blending and mixing of FFT with the overburden Clearwater Shale to form ready-to-reclaim deposits isconsideredahighlysignificantcontributionofthecurrentIRCtotheindustrialpartner. OneofCOSIA’smembercompanieshastakenthisnewtechnologythroughpilotscaletestingandontocommercialscaleimplementationwithgreatsuccess.FurtherresearchisproposedfortheIRCrenewalprogramthatwillextendthetechnologytootherCOSIAmembercompaniesforusewithawiderrangeoftailingsandoverburdenmaterialproperties,andfortheconstructionofdrystacktailingsdepositsthatdonotneedcontainment.

Finally, the current IRC program proposed using unmanned systems to reduce the risk and cost of deployingstandardgeotechnicaltoolsinchallengingterrains(i.e.,oilsandstailingsdeposits).Oilsandstailingsdepositsare


generally soft and not readily accessible to humans and manned vehicles. Robots with low ground pressurerequirements can conduct surveys using automated geotechnical tools and deploy other payloads. During thecurrent IRC, our robots have collected samples from oil sands tailings deposits and deployed terramechanicsinstrumentsforestimatingsoilpropertiesintailingsdepositswithnobearingcapacity.Thisnovelapproachaimstoautomatethestandardgeotechnicaltoolsthathavebeentraditionallyusedtomeasuretheshearstrengthofthe deposits and track changes over time to estimate the time it will take to reach terrestrial reclamation.Additionally,wehaveproposednewtoolstoestimatesoilparametersfromrobot-terraininteractionstocalculatetheshearstrengthoftheterrain. Strengthpropertiescanbeusedtocalculate load-bearing limitsoftheterrainthatarenecessarytotracktheconsolidationperformanceofthedepositandplanforreclamationofthearea.

TheIRCprogramhasconductedhigh-impactresearchandhasextendedmultidisciplinarycollaborationsbetweentheFacultyofEngineeringandFacultyofSciencebyengagingworld-classresearchersintheDepartmentsofCivil&EnvironmentalEngineering,MechanicalEngineeringandEarth&AtmosphericSciences.Forexample,oneprojecthas focused on the novel design of high-resolution field-deployable vane shear test tools to assess theconsolidationandshearstrengthpropertiesofsaturated/unsaturatedoilsandstailings,combiningtheeffortsofaGeotechnical Engineering PhD student and a Mechanical PhD student. Earth & Atmospheric Science andGeotechnical Engineering HQP have collaborated to obtain field measurements to predict the dewateringperformance of current tailings ponds. These are exceptional opportunities for HQP and their supervisors tounderstand the industrial challenges of Alberta’s oil sands frommultiple viewpoints and to enrich the trainingexperienceoftheHQP.

The IRCprogramhastrainedandmentoredsevenPhD,eightMScstudentsandthreepostdoctoral fellows,whohavedemonstrated theirpotential for tremendous impact through their current IRC research. FourofourHQPwon awards from local and national professional engineering societies based on their IRC research papers andpresentations;nineHQPheld24institutionalornational(i.e.,NSERC)scholarships.AnotherHQPhashadmediacoverageofherIRCresearchbyCBC,amongothermediaoutlets,andhasbeeninvitedbyindustrytopresentherIRCresearchseventimes.Ofparticularsignificance,theCanadianDamAssociation(CDA)hasrecognizedourIRCHQPs’significantcontributionstoengineeringpracticeandpotentialforresearchimpactthroughtheawardoftheNational CDA Gary Salmon Memorial Scholarship three years in a row (2016, 2017 and 2018), which isunprecedentedinthehistoryoftheAssociation.

LESSONSLEARNED

Theme1:UnsaturatedSoilMechanicsforOilSandsTailingsDeposition

1.1MethodstoMeasureandPredictDewateringPerformanceofFluidFineTailingsDeposits

i. DevelopempiricalcorrelationbetweentotalsuctionandHyperspectralimageryforthinsectiondryingtestsforarangeofFFT

Atmospheric fines drying with thin lift deposition is used to de-water FFT. Hyperspectral imagery has beenemployedtoquantifytotalsuctionatthesurfaceoftheFFT,which inturncontrolsevaporationanddewateringrates for thedevelopmentof shear strength. In addition, flocculationof the tailings candramatically influencefield performance. This project focused on investigating the potential of hyperspectral imagery tomonitor theflocculationperformanceoftailings.


Inthisstudy,theflocculationperformanceoftailingswasexaminedthroughspectralmeasurementsandensuingimage analysis for flocculated tailings samples generated in the laboratory. The results showed that a ratio ofbandsat1678and1930nm isaneffective spectralmetric toassess the textureof the flocculatedsamplesandrevealdifferencesamongstsamples.Thevariationinthesurfacemicro-topographyofthesamplesappearedtobethemainfactorderivingthevariationinthetexturecapturedbythe1678and1930nmbandratio.Moretexturewasobservedwhenlargerflocswereformedasaresultofabetterflocculationprocess.Thisstudyhasshownthatalthough it is feasible todetectunder-dosedand/orover-sheared samplesusinghyperspectral imagery, furtherflocculation tests are required to calibrate the method, validate the results, and ultimately develop onlineinstrumentationforreal-timeassessmentofflocculationperformance.

BenefitstoCanada:Waterremovalfromsaturatedtailingsisthefirststepindensifyingandconsolidatingtailings.The separationofwater frommature fine tailings (MFT) is thus anoperational andenvironmental challengeoftailingsmanagement. Remote estimation ofmoisture content, evaporation rate, and total suctionwould helpoperatorstoassessthedryingprocess,determinewhenthedeposithasstoppeddrying,anddecidewhenthenextlift should be deposited. Therefore, our work provides low-risk, cost-effective quick surveys to the tailingsoperators to manage their large volume of tailings and thus accelerates the process of converting tailings toreclaimablelandscapes.

ii. UsingECVtoMeasureandPredictDewateringPerformance

In this project, actual evaporation ratesweremeasured using amicrometeorological technique knownas eddycovariance (ECV). TheECVwas installedon a scaffolding system that accessed the centerof thepond. Actualevaporation rateswere found to be low,which suggested that current dryingmodelsmight overestimate howmuchdewateringoccursduetoevaporation.Tocalculatelatentheatflux,requiredfordeterminingevaporationrates,dryairmolarvolumeandthewatermixingratiohadtobemeasured.ThecorevariablesmeasureddirectlybytheECVsystemareambienttemperature,ambientairpressure,mixingratiosofgases,windspeed,andwinddirection.TheECVsystemtakesmeasurementsatafrequencyof10Hz,andthenthemeasurementsarecompiledinto30-minuteintervalsandmeansandstandarddeviationsarecalculated. ThedatawereanalyzedinEddyPro,andinordertocalculatewaterflux,thedryairmolarvolumehadtobedetermined.

BenefitstoCanada: Byhavingaccurateandactualevaporationrates,oilsandsoperatorswouldknowwhenthetailings surfacehas reached its driest state andnew tailings canbeplacedon the surface. Asdifferent tailingsvolumes(liftthicknesses)dryatdifferentrates,theoptimumpointwherethemosttailingsisplacedtodryfortheleast amount of time could be determined. This would ensure that the tailings pond is consolidated to itsmaximumpotential,whichwouldaidinthereclamationofthesetailingsponds.

iii. TailingsCharacterizationUsinganUnmannedGroundRobot

In this project, novel technologies for characterizing soft ground terrains, such as tailings deposits, weredeveloped, including automated vane shear tools that are typically used for laboratory and field campaigns toestimate the deposit’s peak, residual, and remolded shear strength. Additionally, we developed new tools toestimatesoilparametersfromrobot-terrain interactionstocalculatetheshearstrengthofthetailings. Strengthproperties can be used to calculate load-bearing limits of the tailings, which are necessary to track theconsolidationperformanceofthedepositandplanforreclamationofthearea.Finally,wedevelopednoveltoolsfor unmanned robotic systems to reduce the risk and cost of deploying payloads and tools in challenging soft


tailings. Robots have been used to collect samples from previously inaccessible materials and to deployterramechanicsinstrumentsforestimatingsoilpropertiesintailingsdepositswithnobearingcapacity.

BenefitstoCanada:Thedevelopmentofautonomoussystemsforenvironmentalstudiesisgenerallyapplicabletotailingsoperatorsandwill support theefforts for reclamationof tailings impoundments. These systemscanbeusedtoobtaininsitutailingspropertiesfromtreatedfluidfinetailingsdepositsthatarenottrafficable.Thenewtechnologies will enable characterization of deposits that are not available using conventional geotechnicaltooling. This new information will aid in the understanding of how tailings change over time, which is veryimportanttotheoilsandsoperatorsaswellasthedecision-makingonprocesscontrolandpost-depositionwork;andareofdirecteconomicbenefittotheoilsandsindustryandCanada’seconomy.

1.2DeterminationofSaturated/UnsaturatedPropertiesforHighVolumeChangeMaterials

Thisprojectfocusedonthedevelopmentandverificationofarevisedmethodologytoestimatethecoefficientofpermeabilityfunctionandthewaterstoragefunctionforhighvolumechangematerials.Bothdegreeofsaturationandvoidratioweretakenintoaccountwhendevelopingtherevisedtechniquefortheestimationofthecoefficientofpermeability forsoils thatundergovolumechangeassoil suction is increased (e.g.,Reginaclayandoil sandstailings).Thescopeofthisprogramwaslimitedtoatheoreticalstudyandaresearchprograminvestigatingseveralsoilsthatchangevolumeassoilsuctionisincreasedfortheverificationoftheproposedtheory.

Benefits toCanada: Thecoefficientofpermeability functionandthewaterstorage functionare two importanthydraulic properties required in thenumericalmodelingof geotechnical problems such as transient seepageorcontaminant transport that occurs during mine waste or tailings disposal. The inaccurate estimation of thehydraulic propertieswill cause erroneous numericalmodeling results,whichwill then cause engineers tomakeinappropriatedecisionsconcerningaproject.Existingestimationtechniques,suchasthevanGenuchten-Burdine(1980) equation, the van Genuchten-Mualem (1980) equation and the Fredlund, Xing and Huang (1994)permeability function, produce reasonable resultswhen estimating the coefficient of permeability function andthewater storage function forunsaturatedsoilswith lowcompressibility suchas sandsor silts,but theanalysisprotocolsrequirechangeswhenpredictingthecoefficientofpermeabilityandthewaterstorageformaterialsthatundergovolumechangeassoilsuctionchanges(e.g.oilsandstailingsslurry).Therevisedtheorycouldbeappliedinnumericalmodelling to facilitatean improveddesignof tailingsdisposal, reducingpotentialengineeringcoststhatcouldhavebeencausedbydecisionsbasedonmisinformation.

1.3AssessmentofShearStrengthofSaturated/UnsaturatedOilSandsTailings

Thisprojectinvestigatedwhetherfluidfinetailings(FFT),whensubjectedtoanumberoftechnologiestofacilitatethedewateringof FFTdeposits, adhere to theprinciplesof soilmechanicsandgenerate stress-strain curves, aswellasotherengineeringpropertiessuchascompressibilitycurvesandconductivitycurves.Numeroustestswereconductedtocharacterizetheconsolidationbehavioursofoilsandtailings. Largestrainconsolidationtestswereutilized to produce properties, which were used to compute the consolidation behaviour of deposits. Theseproperties were employed in versatile numerical models that can analyze and predict the saturated andunsaturated properties of FFT deposits. The laboratory tests conducted under this programprovide a basis toestablishconstitutiverelationsofdepositedFFTinrelationtothestress–strainstateusingindependentvariables.

BenefitstoCanada:Theresearchfocusedoninvestigatingfundamentalsoilmechanicsprinciplessuchasstress–strain relationships and the engineering properties of FFT under saturated/unsaturated conditions. These


fundamental principleswill be used to predict the behaviours of FFT as accurately as possible by incorporatingthemintoavailablenumericalmodelingsoftware. Subsequently,thesoftwarewillbeusedasatoolforanalysisduringengineeringdesigningat various stages suchasbearing capacityearth fill structures thatwill beusedascontainment.Theresearchprogramwillprovidealaboratorydatasetandanalysisthatleadstowardsnarrowingtheexistingknowledgegapandcontributestowardsresolvingchallengesfacingmineoperators.

1.4ModellingofPoreFluidintheComputationofActualEvaporation

The objective of this research is to evaluate the effects of cyclic freeze-thaw on the suction behaviour ofcentrifuged tailings through a laboratory experimental study. The research seeks to establish the relationshipbetweenthemultiplecyclefreeze-thawprocesses,thesoilsuctionandtheelectricalconductivity. Whetherthiscyclicphenomenoniseffectiveinformingasurfacecrusttoincreaseosmoticsuctionwillalsobeinvestigated.

Testing to obtain geotechnical index properties, solids mineralogy and pore water chemistry was completed.Currently,anexperimentalsetupforrepeatedfreeze-thawcyclesisunderway.Alaboratoryfilterpapertestwillbe conducted to determine the total and matric suctions. The osmotic suction will then be obtained bysubtractingthematricsuctionsfromthetotalsuction. Fiveconsecutivefreezethawcycleswillbeperformedattwodifferenttemperatures.

BenefitstoCanada: Thefindingsofthisresearchworkareexpectedtoestablishandenhanceunderstandingoftheinfluenceoftheeffectsoffreeze-thawcyclesonthesuctionbehaviourofcentrifugedtailings. Knowledgeofthedevelopmentofosmoticsuctionandelectricalconductivitythroughfreeze-thawcyclesisrequiredtoevaluatepotential capping and reclamation schemes in the design and construction of cover systems on centrifugedtailings.

Theme2:ConsolidationProcessesforMatureFineTailings

2.1ObservationsandAnalysisfora30-YearLarge-ScaleConsolidationExperimentandOilSandsMatureFineTailings/2.2TheoryandComputerModellingofSedimentation,ConsolidationandCreepofMFT

Theseresearchprojectsfocusedonsedimentationandconsolidationprocessesgoverningthetransitionofmaturefinetailingstoasoilstate,aswellasfundamentalprocessesforconsolidationandcreepinMFT.Thegoalwastounderstandanddescribe,bothqualitativelyandquantitatively,theprocessesatworkinMFTconsolidationfortheadvancement of our understanding of soft soil behaviour. The data collected during the experiment clearlydemonstratedthatthemajorityofvolumetricdeformationobservedinthetailingsisassociatedwithcreepratherthanwithconsolidation. AmoderntheoryofcreepdeformationbyVermeeretal.(2014)appearstoprovideanadequate fit for thedata,withan important implicationbeing that creep is amajordeformationmechanism inunder-consolidatedsoilssuchasthehighvoidratiooilsandstailings.Thereviewconcludedthatacompressibilityfunction is required to performmodelling using the creep theory by Vermeer et al. Ideally, an odometer testshouldbeconducted,butthistestisnotsuitableforhighvoidratiosoftsoilssuchasMFT.Therefore,alternativetestsmustbeconsidered.Thechiefobjectiveofanyconsolidationtestwouldbetominimizetheamountofcreepthatoccursoverthedurationofasteploading.ThereviewalsoconcludedthatahydraulicconductivityfunctionisrequiredforsuccessfullymodellingthesettlementcolumnbehaviourusingthecreeptheorybyVermeeretal.Thisfunctionisnecessarytoaccountfortheconsolidationprocessesoccurringinparallelwithcreepdeformation.


2.3ModellingMFTConsolidationwithaGeotechnicalCentrifuge

The objective of this research project is tomodify the current geotechnical centrifuge testing procedure of oilsands tailings samples to better represent the field conditions of oil sands tailings ponds. Current testingprocedures do not allow for the continuous addition of tailingsmaterial during the centrifuge testing. This isequivalent to the instantaneous fillingofa tailingspond in the field; therefore, centrifuge test resultsusing thiscurrentmethodmayprovideerroneousresults.Bymodifyingthecentrifugetesttoacceptcontinuousadditionoftailingsmaterialduringtestingandcomparingtheseresults to thoseobtainedbytheoriginal testingprocedure,wecanbetterrepresentthefieldconditionsofanactualoilsandstailingspond.

The experimental procedure for this research project was to modify the current testing procedure in thegeotechnical centrifuge to accommodate the layered addition of test material during the centrifuge cycle.Laboratorycharacterizationofthechosentestmaterialsandtworoundsofcentrifugetestshavebeencompleted.Results from the different test procedures included settlement curves, void ratio profiles, compressibilityparametersandsegregation(foroilsandstailingstestmaterials).

Benefits to Canada: This research provides the opportunity to improve understanding of the consolidationbehaviourofoil sands tailings through testing inageotechnical centrifuge. Resultsobtained fromthis researchproject will also guide future experimental design for the testing of oil sands tailings using the geotechnicalcentrifuge. Understandingtheconsolidationbehaviourandcorrect interpretationoftestresults iscrucialtotheprediction and modelling of the long-term behaviour of the tailings deposits as required for reclamation andclosureactivities.

Theme3:AssessingandImprovingDepositionofTailings

3.1DeepFines-Dominated(Cohesive)Deposits

This research evaluates the effect of natural conditions (repeated freeze-thaw cycles, summer drying andprecipitation)onthestrengthofexistingtreatedcentrifugedtailingsdepositspriortoreclamation.Thisresearchaimstoseewhetherthemultiplecyclicfreezeandthawprocessiseffectiveinformingasurfacecrustcapableofgainingsufficientstrength.Theresearchhastwocomponents:acomprehensivelaboratorytestingandnumericalsimulation.Inthefirstphase,cyclicfreezethawtestswerefollowedbyatmosphericdryingandre-wettingteststodepict summer drying and rainfall events, respectively. Conversely, the second phase depicted the combinedeffectofdrying-wettingbetweeneachfreezethawcyclethatrepresentsseasonalweathering.Finally,theresultsofthelabtestsarebeingimplementedinnumericalmodellingtodevelopthethermalpropertiesoftailings.Thenumericalsimulationwillpredicthowdeepacertaindepositwillfreezeandthawanddevelopshearstrengthinaparticularseason.Basedonthenumericalanalysis,thetimerequiredfordevelopingacrustcanbeestimatedandthus,anapproximatetimeofexposingthetailingspondtotheatmospherepriorcappingcanbepredictedthatcansaveasignificantreclamationcost.

TheHQPiscompletinglabworkandnumericalmodellingthatcanillustratehowdeepacertaindepositwillfreezeand thaw in a particular season. Field deposit data has been provided by two mine operators and will becomparedwiththefindingsofthelabandnumericalmodelingresults. Cyclicfreeze-thawtestsshowedthattheundrainedshearstrengthcanbeincreasedjustbyexposingthetailingstotheatmosphere.Furtherseparationofwaterfromthickenedtailingsisachallengingtaskoftailingsmanagement.Therefore,thecorrectinterpretationofthe effect of seasonal weathering can potentially help the operators to decide when the next lift should bedepositedorwhenreclamationcoversystemscanbeplaced.


BenefitstoCanada:Theresearchisexpectedtoestablishanenhancedunderstandingofthevolumechangeandengineering behaviour of deep tailings deposits exposed to surficial seasonal weathering. Understanding thedevelopmentofasurficialcrustisrequiredtoevaluatepotentialcappingandreclamationscenariosandultimatelyguidethedesignandconstructionofreclamationcoversystemsondeeptailingsdeposits.Thisworkwillprovidedesigncriteriaanddatathatwillaidinthedesignofclosurelandformsfortailingsdeposits.

3.2Co-depositionandBlendingofFluidFineTailingswithOverburden

This project is focused on applying the “co-deposition” technique to oil sandsmining;mixing fluid tailingswithClearwatershaleoverburden.AseriesofconsolidationtestswerecompletedatUniversityofQueenslandin2017,incollaborationwithDr.DavidWilliams. Aspecialisedslurryconsolidometercellwasusedtosimulatetherapidplacementofco-disposalstacksandthenusedtomeasurethegenerationanddissipationofexcessporepressure.Testswerecarriedoutonarangeofshalelithologies,mixratiosandinitialsampleheights.Theresultsshowthepotentialforlargegenerationofporepressuresexists;however,itisdependentuponthemixratio.Dissipationofexcess pore pressure is governed by both consolidation and transfer ofmoisture from theMFT into the shalelumps. Themoisture transferprocessoccursquickly andallows for rapid constructionof stable stacks, suchasthosethathavealreadybeendemonstratedinthefieldtrials.Consolidationalonewouldtakemanyyears.

Followingthesuccessoftheinitialcomputedtomography(CT)scanningtrialatAlbertaInnovates,asecond,morecomprehensive test was run. CT scanners measure x-ray attenuation; this can be calibrated to density (ormoisturecontent).Laboratorytestingwascarriedouttodeterminethein-situdensityoftheshalelumps.Basedon this a sample was prepared such that the volumetric mix ratio at initial conditions was precisely known,enablingthex-rayattenuationthresholdsforshalelumpsandtailingstobedetermined.Thisenabledcalibrationofthescanner.

Analysis of the testing is still underway. Possible next steps include comparing the measured results to atheoreticalmodel based upon unsaturated soilmechanics principles, and running further tests at differentmixratios. Field trials consistingof test piles of blendedKc and tailingsmaterials at a rangeof solids contents arecurrently in progress at an oil sands operator’s mine site. Core samples have been obtained for testing. Thistogetherwith cone penetration testing data from themine sitewill be very useful for verifying and calibratingmodelsthatarebaseduponlaboratorydata.

Benefits to Canada: Dewatering of MFT remains a significant, largely unresolved challenge, and complicatesreclamation and closure. Whilst most approaches currently in use or development aim to increase the solidscontentoftheFFTbyremovingwater,thecurrentprojectaimsatincreasingthesolidscontentbyaddingsolids.Thishasgreatpotentialbecauseofthehighwaterabsorptioncapacityoftheoverburdenmaterial.TheClearwaterformationoftenhasnaturalwatercontentsbelowtheplasticlimit.Uponmixing,waterisrapidlytransferredfromtheMFTtotheshale.Earlyindicationshaveshownthatthiscancreateastablematerialwithshearstrengthsinexcessof5kPa,eliminatingtheneedforcontainmentandhavingthepotentialtocreatepost-closureterrestriallandscapes.

Theme4:TailingsSimulationModellingandLong-termBehaviourofFineTailings

4.1AssessmentandSimulationofTailingsDewateringMethods

i. CouplingFreeze-thawandDesiccationDewateringCodesintoOneCommonModellingPlatformUsingMATLAB


Thisprojectaimedtodevelopacomputerprogramtosimulatethedewateringofthickenedtailingsusingnaturalprocesses,includingfreeze-thaw,consolidationanddesiccation,whicharerelevanttotheoilsandsindustryintheFortMcMurrayregion.Thecodedevelopedunderthisprogram,FTCD(Freeze-Thaw-Consolidation-Desiccation),iscurrentlybeingtrialedinindustry.

ii. ValidatingtheFreeze-thawandDesiccationDewateringModelswithLaboratoryandFieldDataforFlocculatedFluid Fine Tailings. Using TMSim and FTCD, Investigate Operating Strategies and Design Alternatives toImproveThinLiftDewateringProcesses

Tailingsplanningisaniterativeandcomplexprocessthatinvolvesamultitudeofphysicalandchemicalprocessesover time with both deterministic and stochastic components. The numerical model in this project adopts aSystemDynamics approach that is frequently used in business, ecology and public health, but rarely in tailingsmanagement.TheSystemDynamics(SD)techniqueiswellsuitedforhigh-levelmodellingofinter-relatedsystemsacross disciplinary boundaries. In a SD-based model, both quantitative and qualitative or even tentativeknowledgeareincorporated.Theeasewithwhichcausalloopdiagramming(CLD)methodcanbetaughtallowsforparticipatorymodelling from non-technical stakeholders. The quantitative processes use GoldSim as themainsimulationenginewithspreadsheetasuserinputsupport.

Severalmodifications and extensions to the TailingsManagement Simulation (TMSim)modelling software havebeen made, including construction of concept maps using System Dynamics and Causal Loop diagrammingmethods and the stochastic simulation of tailings consolidation process using nestedMonte Carlo techniques.Currently, thestudentresearcher iscreatingan integratedmodel linkingtailingsconsolidationwithcaporcoverperformance, calibrating and validating the integrated model, and evaluating the impact of initial tailingspropertiesonthecappingperformanceduringclosure.

BenefitstoCanada:Theintegratedmodelprovidesaquickmethodtotesthypothesesandgaininsightsintotheinteractionbetweencappingmaterialandtailingssubstrateoverthelongterm.Itcanbeusedbyregulatorsandproducers as a high-level analytical tool for due diligence and regulatory audits; builds a common qualitativelanguage for interdisciplinarycollaboration;and fosters thecultureofparticipatorymodellingacrossdisciplinaryboundaries and among non-technical stakeholders. This model also brings transparency and flexibility to themodellingprocess(asopposedtotheblack-boxcommercialmodels).

4.2InfluenceofChemicalAmendmentsandDewateringProcessesontheGeotechnicalBehaviourofOilSandsTailingsFines

i. Short-termEffectsonGeotechnicalBehaviour

Large volumes of fluid fine tailings (FFT) fromoil sandsmining operations pose difficult engineering challengesbecausetheydonotreadilydewaterand,duetotheirfluidstate,requirecontainment. AcommonapproachtoreduceFFTvolumebywaterremovalistotreattheclaysuspensionwithacoagulantandflocculanttoformhighlyporousaggregatescalledflocs.Thisworkinvestigatedtheeffectofincreasedflocsizeongeotechnicalpropertiesof FFT. A method utilizing a flocculation system and images of flocs was developed to determine floc sizedistributionofatreatedFFTsample.Flocsizewasmeasuredwithimageanalysissoftwareusingimagesobtaineddirectly after flocculation. Treatment recipes, combining an optimal dose of coagulant and polymer, weredesignedtogiveclearreleasewaterandhighlyvisibleflocssuitableformeasurement.Flocsizedistributionswerethendetermined foreachof theoptimal treatments. Twoof these treatmentswere furtheranalyzed toassess


compressibility, hydraulic conductivity, and vane shear strength. Both compressibility and vane shear strengthwere foundtobesensitive tochanges in flocsizedistributionwhilehydraulicconductivitydidnotappear tobelargelyimpactedbyflocsize.

Benefits toCanada: This researchbuilds towardtechnologiesandprocesses that removewater fromsaturatedtailingstoassistindensifyingandconsolidatingthetailings.Theultimategoalisforoilsandsoperatorstomanagethe dewatering of tailings prior to deposition in tailings dams, which require more intensive reclamationtechnologies. This research contributes to industry’s goals of accelerating the process of converting tailings toreclaimablelandscapes.

ii. Long-termEffectsonGeotechnicalBehaviour

Theobjectiveofthisresearchistodeterminetheinfluenceofchemicalamendmentdegradationonthelong-termgeotechnicalbehaviourofoilsandstailings.TheimpactofagingontheshearstrengthofpolymeramendedFFTisbeinginvestigatedcurrently.In2017,auniqueopportunityexistedtodeconstructandcharacterizeanoldflumetestcontainingflocculated/dewateredtailings.Thiswillhelpassesswhethertheagingofthetailings(>3years)hasanimpactonthegeotechnicalparameters.Inthelaboratorytestingprogram,sampleswerecuredtodegradetheflocculanttoprovideaconservativerepresentationoftailingsthathaveundergonesomelevelofdegradationofthe flocculants. The tailings sampleswere fully characterizedbeforeandafter thecuringprocess toassessanychangesinthegeotechnicalbehaviour.Themicrostructureofthetailingsbeforeandaftercuringtreatmentwasalsoassessed. Geotechnical indexpropertieswerealso investigatedtodeterminethegeotechnicalbehaviourofas-receivedtailings.Tailingswithvoidratiosrangingfrom2to1willbeusedtosimulatetheadditionalimpactofconsolidationontheshearstrengthofpolymeramendedtailings.

Benefits to Canada: This research provides the opportunity to further understand the long-term strengthbehaviour of amended tailings deposits. Currently available correlations of strength tomaterial characteristicssuch as clay to water ratio or void ratio may not account for changes in strength with time (thixotropy) orsensitivity. Agoodunderstandingof the transientnatureof thestrengthof tailingsdeposits is required for thedesignof the capping and reclamation. This informationwill ultimately guide thedesign and constructionof acoversystemonflocculated/dewateredtailingsdepositsintheoilsands.

4.3FreezingCharacteristicsofFluidFineTailingsandtheirRelationtoUnsaturatedSoilProperties

The objective of this research is to assess the validity of using a soil freezing characteristic curves (SFCC) toestimatethesoilwatercharacteristiccurve(SWCC)forfinegrainedtailingslikeoilsandsFFT.Alaboratorytestingprogramwas developed to determine the SFCC. To determine the validity of the SFCC to estimate the SWCC,conventional SWCC measurements were conducted on samples of different types of tailings. SFCC and SWCCtesting was completed on Devon silt, gold tailings, copper tailings, and an oil sands centrifuge cake. Thesematerialswere selected for testing to assess the validity of using SFCCs to estimate the SWCC for fine grainedtailingssuchasoilsandsFFTandthendefiningtherangeofslurrytailingsforwhichthismethodmaybeapplicable.

ThemeasuredSFCCswereusedtoestimatetheSWCC.TheestimatedSWCCswerecomparedtoSWCCsmeasuredusingtraditionalmethods. Basedontheresultsofthetesting,anumberofkeyconclusionscanbemade. First,themethodappearstobeapplicabletometaltailingsthathavelargequantitiesofsandsizedparticleswithsomedegreeoffines.Second,thisestimationtechniquerequiresthatthesoilbeclassifiedascolloidalornon-colloidalforselectionofasoildependentconstant.However,itcanbedifficulttoclassifycertainsoilsaspurelycolloidalor


non-colloidal,aswiththecoppertailingsinthisresearch.Thislimitstheapplicabilityofthismethod.Regardless,thismethodisusefulasascreeningtoolasitcanbeusedtorapidlytestalargenumberoftailingstodecidewhichmaterialsshouldhavedetailedtraditionalSWCCsconducted. Third, itdoesnotappearthat thismethodcanbeusedtoestimatetheSWCCfromtheSFCCforoil sandstailings. This isattributedtothehighclaycontent (andassociated adsorbedwater) andwater content of the tailings. Based on the results of the testing, it does notappearthatthesalinityofthecentrifugecakeisresponsibleforthemismatchbetweentheSWCCestimatedfromthe SFCC and the SWCCmeasured using traditionalmethods. Finally, estimating the SWCC from the SFCC formetal tailings ismuchmoreaccurate thanestimating it fromthegrainsizedistribution. TheSFCC isperformeddirectly on the soil. This is a significant advantage over estimating the SWCC from the grain size distribution,especiallysincethismethodgenerallyisnotrecommendedforman-madematerials.

BenefitstoCanada: Asdiscussed,theSWCCistime-consumingandchallengingtodetermine. Asingletestcantakeanywherefromweekstomonthstocomplete.TheSFCCtesttakesapproximatelytwodaystoperform.ThisisagreatadvantageovertheSWCC. Ultimately,thismethodwouldprovideanalternativetoatime-consumingtestwhichisadvantageous,astheSWCCisneededtopredicttherateofdewateringandmagnitudeofstrengthgainduringdesiccationdewatering. Overall,theexperimentalmethodproducedrepeatableandreliableresults.TheresultsshowedthattheSWCCcouldbeestimatedfromtheSFCCfortailingsfrommetalmines(goldtailingsandcoppertailings)withahighportionofsandandasmallamountofclay.TheSFCCwasnotabletoestimatetheSWCCforoilsandstailings.Regardless,thismethodishighlypromisingasascreeningtooltorapidlytestawidevarietyoftailingstodeterminewhichshouldhaveadditionaltraditionalSWCCtesting.

4.4LandscapeArchitectureandEngineeringDesignforMinedEarthStructuresandReclamation

There are over 20 above-ground tailings dams currently built or proposed in northern Alberta, which willeventually need to be decommissioned (“closed”) and re-integrated into the post-mining landscape. Whiledesigningforstabilityandoptimalfunctionalitythroughouttheoperationallifeisimperative,ashiftintherelativeimportanceofforcesactingandcorrespondingfailuremechanismsoccurspost-closure.Forexample,porewaterpressureriseduetopondfillingmaybeariskduringoperation;thisisnolongerafailuremechanismoncefillingceases. Forces that rouse little concern through the active dam stage eventually dictate the stability andfunctionalityofthesestructuresoncetheytransitionfromadamintoa landform. Thesedominantpost-closureforcesareactingonthe landforms/dams inperpetuityasopposedtoasettimeperiod,makingthemequallyasimportant as those acting throughout operation; as such, they too require considerationwhen these dams arebeinginitiallydesigned.

As global best practices in tailings dam design for closuremove towards a design-life in excess of 1000-years,geomorphicchangesneedtobeconsideredas theymaythreatenstabilityandfinescontainmentover this timeframe. Thisresearchproposesasecondarystage indamdesign, followingtraditionalassessmentmethods,thatuseslandscapeevolutionmodelstoidentifyerosionproneareas,excessiveflowvelocities,highdepositionzones,etc.suchthatthedamdesigncanbemodifiedforoptimalclosureperformanceoverlongtimeframes.

TheimmediatebenefitofLandscapeEvolutionModellingwithregardtoringdykesisthatanentirelandformcanbemodelledas it isexposed toprecipitationover long time frames (10 -1000years). Areasofconcerncanbehighlighted early and dam designs altered such that post-closure work, maintenance, and downstreamenvironmentaldegradationarereduced.Thisresearchisanticipatedtoassistindeterminingwhetherdamdesignsare likely to meet closure criteria (withstand Probable Maximum Precipitation-PMP events, flow velocity


thresholds, sediment loads, etc.), in turn providing less liability and more stable structures moving forward.Progress has continued on the landform evolution modelling component of this research, and a quantitativeinventoryandclassificationoferosional featuresonanoilsandstailingsfacilitywascompleted. Climatechangewill be integrated into the 100-year model to learn how recent climate scenarios are likely to alter landformperformance. Additionally, erosion mitigation techniques will be modelled in order to evaluate relativeeffectiveness.

BenefitstoCanada:Erosionofoilsandtailingsdamshasbeenaknownconcernsincethe1970s,buthasnotbeenstudiedindetailorevaluatedtodeterminecause,characteristics,orquantitysuchthattheriskisfullyunderstood.This erosionquantificationworkprovides evidenceof the geomorphic processes actively takingplaceon abovegroundtailingsdamsintheoilsandssuchthatindustrymaybebetterpreparedtoreclaimandidentifyproblemspost-closure.Giventhesizeoftheoilsandsminingregion,post-closuremonitoringisexpectedtobeagrandioseundertakingintermsofeffortandcost.Theremotemethodstestedinthisprojectprovideacost-effectivetooltoaidregulatorsandoilsandcompaniesinevaluatinglandscapeperformanceduringactiveandpassivereclamationstages.


PublishedTheses

Schafer,H.2018.FreezingCharacteristicsofMineWasteTailingsandtheirRelationtoUnsaturatedSoilProperties.MScThesis,DepartmentofCivil&EnvironmentalEngineering,UniversityofAlberta,Edmonton,Alberta.

Ogloza, J. 2017. Measuring Actual Evaporation Rates from a Tailings Pond. MSc Thesis, Department of Civil &EnvironmentalEngineering,UniversityofAlberta,Edmonton,Alberta.

Entezari,I.2016.ApplicationsofremotehyperspectralsensinginthecharacterizationofAlberta'soilsandstailings.PhDThesis,DepartmentofEarthandAtmosphericSciences,UniversityofAlberta.

Zabolotnii,E.2016.RoadmaptoFinalizingthe30-YearSettlementColumnExperiment.MEngReport,DepartmentofEarthandAtmosphericSciences,UniversityofAlberta.

Zhang,F.2016.UnsaturatedSoilPropertyFunctionsforHighVolumeChangeMaterials.PhDThesis,DepartmentofCivil&EnvironmentalEngineering,UniversityofAlberta.

JournalPublications

Entezari,I.,Rivard,B.,Vajihinejad,V.,Wilson,G.W.,Soares,J.,Fisseha,B.,andBeier,N.2018.MonitoringTailingsFlocculationPerformanceUsingHyperspectralImagery.CanadianJournalofChemicalEngineering.Submitted.

Entezari,I.,Rivard,B.,Lipsett,M.G.Predictingtheabundanceofclaysandquartzinoilsandsusinghyperspectralmeasurements.Accepted.InternationalJournalofAppliedEarthObservation&Geoinformation.

Schafer, H., and Beier, N.A. Estimating the SWCC from the SFCC for mine waste tailings using TDR. Accepted.CanadianGeotechnicalJournal.


Slingerland, N., Beier, N.A. andWilson, G.W. Oil sands tailings dam design considerations for ease of closure.Submitted.CanadianInstituteofMining,MetallurgyandPetroleumJournal.

Slingerland,N.,Sommerville,A.,O’Leary,D.,Beier,N.A.Identificationandmeasurementoferosiononanoilsandstailingsdam.Submitted.Geomorphology.

Kabwe,L.K.,Scott,J.D.,BeierN.A.andWilson,G.W.2018.EnvironmentalImplicationsofEndPitLakesatOilSandsMines.EnvironmentalGeotechnics,ICEJournal.Accepted.

Kabwe, L.K.,Wilson, G.W., Beier N.A. and Scott, J.D. 2018. Effects of Atmospheric Drying and Consolidation ofFlocculatedThickenedTailingsandCentrifugedCakeonNear-SurfaceShearStrength.SpecialarticleofTheSecondPan-AmConferenceonUnsaturatedSoils,Dallas,2017,PublishedintheJournalofASCEJune20,2018.

Slingerland,N.,BeierN.A. andWilson,G.W.2018.Enhancedgeomorphicdesign for reclamationof ruralwaste-scapes.DetritusJournal,Vol1(2).

Zhang, F.,Wilson, G.W. and Fredlund, D.G. 2018. Estimation of permeability functions for Bulyanhulu Tailings.GeotechnicalTestingJournal.doi:10.1520/GTJ20170303.

Jeeravipoolvarn, S., Miller, W., Scott, J.D., Kabwe, L.K. and Wilson, G.W. 2017. Modeling Effect of BitumenExtractionProcessesonOilSandsTailingsPonds".JournalofCivilEngineering&Architecture,11:48-59.

Kabwe, L.K.,Wilson, G.W., Beier N.A. and Scott, J.D. 2017. Effect of various treatments on consolidation of oilsandsfluidfinetailings.CanadianGeotechnicalJournal.

Zhang,F.,Wilson,G.W.andFredlund,D.G.2017.Permeability function foroil sands tailingsundergoingvolumechangeduringdrying.CanadianGeotechnicalJournal,55(2):191-207.

Beier, N.A., Kabwe, L.K., Scott, J.D., Pham, N.H. and Wilson, G.W. 2016. Modeling the effect of flocculation,thickening and desiccation on oil sands tailings. Geotechnical Special Publication No. 270: Geotechnics forSustainable Energy – Selected Papers from Sessions of Geo-Chicago 2016. Eds. A. Farid, A. De, K.R. Reddy, N.YesillerandD.Zekkos.

Entezari, I., Rivard, B., Lipsett, M.G. and Wilson, G.W. 2016. Prediction of Water Content and NormalizedEvaporationfromOilSandsSoftTailingsSurfaceUsingHyperspectralObservations.CanadianGeotechnicalJournal,53(10):1742-1750.

Olmedo, N.A. and Lipsett, M.G. 2016. Design and field experimentation of a robotic system for tailingscharacterization.JournalofUnmannedVehicleSystems,4(3):169-192.

Zhang, F., Fredlund, D.G. and Wilson, G.W. 2016. Water permeability function for soils that undergo volumechangeassuctionchanges.IndianGeotechnicalJournal,46(3):210-227.

Zhang, F. andFredlund,D.G.2015.Examinationof theestimationof relativepermeability forunsaturated soils.CanadianGeotechnicalJournal,52(12):2077-2087.



Burden, R.N. and Wilson, G.W. 2018. Simulating deposition of Clearwater shale – FFT blends using a novelconsolidationtest.PresentationattheCOSIAInnovationSummit,Calgary,AB:June7-8,2018.

Entezari,I.,Rivard,B.,Vajihinejad,V.,Wilson,G.W.,Soares,J.,Fisseha,B.,andBeier,N.2018.AssessmentoftheTailingsFlocculationPerformanceUsingHyperspectral Imagery.Sixth InternationalOilSandsTailingsConference(IOSTC2018).

Hall,T.,Beier,N.andChalaturnyk.R.2018.InfluenceofFillSchemeonOilSandsTailingsConsolidationModellinginaGeotechnicalCentrifuge.SixthInternationalOilSandsTailingsConference(IOSTC2018).

Fisseha,B.T.,Wilson,G.W.,andSimms,P.H.2018.Assessmentofself-weightconsolidationofflocculatedfluidfinetailings under various environmental conditions. Proceedings of the 21st international seminar of paste andthickenedtailings,Perth,WA,April11-13,2018.

Olmedo,N.A., Lipsett,M.G., Zhang,H. andWilson,G.W.2018.Robotic Systems for EnvironmentalMonitoring -Applicationsforterraincharacterizationinoilsandstailings.PosterpresentationattheCOSIAInnovationSummit,Calgary,AB:June7-8,2018.

Olmedo,N.A.,Lipsett,M.G.,Zhang,H.andWilson,G.W.2018.Tailingsmonitoringusinglow-costsciencestations.PosterpresentationattheCOSIAInnovationSummit,Calgary,AB:June7-8,2018.

Rima, U. and Beier, N. 2018. Effects of Surficial Seasonal Weathering on Centrifuged Oil Sands Tailings. SixthInternationalOilSandsTailingsConference(IOSTC2018),December9-12,2018.

Rima, U. and Beier, N. 2018. Evaluation of Temperature and Multiple Freeze-Thaw Effects on the StrengthProperties of Centrifuged Tailings. Poster presentation at the COSIA Innovation Summit, Calgary, AB: June 7-8,2018.

Schafer,H.L.,Beier,N.A.,Slingerland,N.andMacciotta,R.2018.OverviewofCurrentStateofPracticeforClosureofTailingsDams.SixthInternationalOilSandsTailingsConference(IOSTC2018),December9-12,2018.

Slingerland,N.,BeierN.A.andWilson,G.W.2018.Landscapeevolutionmodellingoflargesanddams.InternationalMineClosureConference.Leipzig,Germany.

Slingerland,N.,Isidoro,A.,Fernandez,S.,Beier,N.A.andWilson,G.W.2018.Geomorphicanalysisfortailingsdamdesigninconsiderationofa1000-yearclosuredesignlife.PlanningforClosureconference.Santiago,Chile.

Zheng, T. and Beier, N. 2018. System Dynamics Approach to TailingsManagement. Presentation at the COSIAInnovationSummit,Calgary,Alberta,June7-8,2018.

Zheng, T. and Beier, N. 2018. Stochastic Simulation of Tailings Consolidation Process. Canadian GeotechnicalConference.EdmontonAB.

Zheng,T.andBeier,N.2018.SystemDynamicsApproachtoTailingsManagementSimulation.TailingsandMineWaste.Keystone,Colorado.


Burden,R.N.andWilson,G.W.2017.Co-deposition:BlendingofFFTandoverburdenmaterials.Proceedingsofthe2017Tailings&MineWasteConference,Banff,AB:November5-8,2017.

Elias, J. and Beier, N.A. 2017. Effect of floc size on geotechnical properties of oil sands fluid fine tailings:Experimentalstudy.Proceedingsofthe2017Tailings&MineWasteConference,Banff,AB:November5-8,2017.

Fisseha,B.,Wilson,G.W.andFredlund,D.2017.Large-StrainConsolidationColumnwithAppliedNegativeWaterPressure.ProceedingsofthePan-Am-UNSAT2017:SecondPanAmericanConferenceonUnsaturatedSoils,Dallas,TX:November12-15,2017.

Fisseha, B. and Fredlund, D. 2017. Assessment of Large-strain Consolidation and Shear Strength ofSaturated/Unsaturated Fluid Fine Tailings. Proceedings of GeoOttawa: 70th Canadian Geotechnical Conference,Ottawa,ON:October1-4,2017.

Fredlund, D.G., and Zhang, F. 2017. Effect of initial conditions on the interpretation of soil-water characteristiccurves(SWCCs)ingeotechnicalengineering.ProceedingsoftheSecondPan-AmConferenceonUnsaturatedSoils,Dallas,TX.,Nov.12-15.

Kabwe,L.K.,Wilson,G.W.,Beier,N.A.,Cunningham,K.A.andScott,J.D.2017.Geotechnicalcharacterizationofatwo-yearoldthickcentrifugeproductdepositsubjectedtoonecycleoffreeze&thawtreatmentunderlaboratorycontrolledconditions.Proceedingsofthe2017Tailings&MineWasteConference,Banff,AB:November5-8,2017.

Kabwe, L.K., Wilson, G.W., Beier, N.A. and Scott, J.D. 2017. Evaluation of various drying processes to furtherincreasesolidscontentandshearstrengthoftreatedfluidfinetailings.ProceedingsoftheCanadianGeotechnicalConference,Ottawa,ON.

Kabwe, L.K., Wilson, G.W., Beier N.A. and Scott, J.D. 2017. Oil Sands Tailings Centrifuge Cake Subjected toFreeze/Thaw.ProceedingsoftheTailings&MineWasteConference,Banff,AB:November5-8.

Olmedo, N.A., Lipsett, M.G., Zhang, H. and Wilson, G.W. 2017. Design and field experimentation of a roboticsystemfortailingscharacterization.PosterpresentationattheCOSIAInnovationSummit,Calgary,AB:March21-22,2017.

Schafer,H.,Beier,N.2017.DevelopmentofSoilFreezingCharacteristicCurvesforFluidFineTailingsusingTDR.InProceedingsofthe70thCanadianGeotechnicalConference,Ottawa,Ontario,2-4October2017.

Schafer,H.andBeier,N.2017.FreezingCharacteristicsofFluidFineTailingsandtheirRelationtoUnsaturatedSoilProperties.PosterpresentationattheCOSIAInnovationSummit,Calgary,AB:March21-22,2017.

Slingerland,N.andBeier,N.A.2017.Enhancedgeomorphicdesignforruralwaste-scapes.Proceedingsofthe16thInternationalWasteManagementandLandfillSymposium.Cagliari,Italy.InternationalWasteWorkingGroup.

Zhang, F., Fredlund, D.G., and Wilson, G.W. 2017. Hydraulic properties for Bulyanhulu tailings during drying.ProceedingsoftheSecondPan-AmConferenceonUnsaturatedSoils,Dallas,TX.,November12-15,2017.


Zhang,F.,Wilson,G.W.,andFredlund,D.G.2017.HydraulicpropertiesforDevonsiltconsideringvolumechangeduringdrying.ProceedingsofGeo-Ottawa2017,Ottawa,ON,October1-4.

Beier, N., Kabwe, L., Scott, J.D., Pham, N. and Wilson, G.W. 2016. Modeling the effect of flocculation anddesiccation on oil sands tailings.GEO-CHICAGO2016: Sustainability, Energy, and theGeoenvironment, Chicago,UnitedStates.

Burden, R.N. andWilson, G.W. 2016. Co-deposition: Blending of FFTwith overburden. Proceedings of the FifthInternationalOilSandsTailingsConference,LakeLouise,AB:December4-7,2016.

Entezari,I.,Rivard,B.,Lipsett,M.G.andWilson,G.W.2016.HyperspectralSensinginSupportofOilSandsTailingsOperationandManagement.ProceedingsoftheFifthInternationalOilSandsTailingsConference,LakeLouise,AB:December4-7,2016.

McKenna,G.,Mann,V.,Fisseha,B.,Beier,N.andOlmedo,N.2016.Thegeotechnicalvaneshearstrengthofminetailings compared to soft foods. Fifth InternationalOil Sands Tailings Conference. Lake Louise, Alberta, Canada.December4-7,pp.329-339.

Olmedo,N.,Lipsett,M.G.andWilson,G.W.2016.Advancedroboticpayloadsformeasuringpropertiesoftailingsdeposits. Proceedings of the Fifth International Oil Sands Tailings Conference, Lake Louise, AB: December 4-7,2016.

Schafer,H.andBeier,N.2016.FreezingCharacteristicsofFluidFineTailingsandtheirRelationtoUnsaturatedSoilProperties.Proceedingsofthe5thCanadianYoungGeotechnicalEngineers&GeoscientistsConference,Whistler,BritishColumbia,29September-1October2016.

Slingerland,N.andBeier,N.A.2016.Aregionalviewofsite-scaledecisions.ProceedingsoftheFifthInternationalOilSandsTailingsConference,LakeLouise,AB:December4-7,2016.

Entezari, I., Rivard, B., Lipsett, M.G., and Wilson, G.W. 2015. Application of Hyperspectral Technology for theEstimationofMethyleneBlueIndexinOilSandTailings.ProceedingsoftheCOSIA/PTACOilSandsClayWorkshopandConference,Edmonton,AB:April28-29,2015.

Kabwe,L.K.,Scott,J.D.,BeierN.A.andWilson,G.W.2015.EnvironmentalImplicationsofEndPitLakesatOilSandsMines.ProceedingsoftheGeo-EnvironmentalEngineeringConference,Montreal,PQ,May21-22.

Kabwe, L.K., Wilson, G.W., Scott, J.D., Sorta, A. and Beier, N.A. 2015. Effect of flocculent treatments onconsolidation of oil sand fluid fine tailings. Proceedings of the 68th CanadianGeotechnical Conference and 7thCanadianPermafrostConference,QuebecCity,September20-23,2015.

Leigh, A., Pineau, J., Olmedo, N. and Zhang, H. 2015. Person Tracking and Following with 2D Laser Scanners.Proceedings of the IEEE International Conference on Robotics and Automation 2015, Seattle,WA:May 26-30,2015.

Slingerland,N.andWilson,G.W.2015.Endland-useasaguideforintegratedmineplanningandclosuredesign.InFourie,A.,Tibbett,M.(eds).MineClosure2015.Proceedingsofthe10thInternationalMineClosureConference,Vancouver,BC.AustralianCentreforGeomechanics,WesternAustralia.


Sorta, A., Beier, N.A., Kabwe, L.K., Scott, J.D. and Wilson, G.W. 2015. The case for using fines void ratio.Proceedings of the 68th Canadian Geotechnical Conference and 7th Canadian Permafrost Conference, QuebecCity,September20-23,2015.

Wilson,G.W.2015.InnovationsinOilSandTailingsGeotechniqueforFluidFineTailingsManagement.KeynoteatSymposium2015MinesandtheEnvironment,Rouyn-Noranda,QC.

Wilson,G.W., Kabwe, L.K., Beier,N.A. and Scott, J.D. 2015. Effect of various treatments on consolidation of oilsandsfluidfinetailings.ProceedingsoftheCanadianGeotechnicalConference,Quebec,PQ.

Zhang,F.,Fredlund,D.G.,Fredlund,M.D.andWilson,G.W.2015.Roleofair-entryvalueandchoiceofSWCCinthepredictionof theunsaturatedpermeability.Proceedingsof the68thCanadianGeotechnicalConferenceand7thCanadianPermafrostConference,QuebecCity,September20-23,2015.

Zhang,F.,Fredlund,D.G.andWilson,G.W.2015.Hydraulicpropertiesforsoilsthatundergovolumechangeassoilsuctionisincreased.AP-UNSAT2015,Guilin,China:October23-26,2015.

Anglow,W.,Wilson,G.W.,Sego,D.C.,Kabwe,L.K.andKan,J.2014.Fieldandlaboratorygeotechnicalpropertiesofoilsandstailingsbeachdepositsinflumetests.ProceedingsoftheCanadianGeotechnicalConference,Regina,SK.

Entezari, I., Rivard, B., Lipsett, M., Feng, J. and Wilson, G.W. 2014. Deployment of Hyperspectral ImagingInstruments for RemoteMonitoring of Soft TailingsWater Content. Proceedings of the Fourth InternationalOilSandsTailingsConference,LakeLouise,AB:December7-10,2014.

Entezari, I., Rivard, B., Lipsett, M.G. and Wilson, G.W. 2014. Estimation of Moisture Content and Activity ofOilsandsTailingsUsingHyperspectralTechniques.IEEEInternationalGeoscienceandRemoteSensingSymposium(IGARSS2014),QuebecCity,QC:July13-18,2014.

Kabwe,L.K.,Wilson,G.W.andScott,J.D.2014.InfluenceofanUnderlyingSandBeachonDrainageandDesiccationofFineTailings.FourthInternationalOilSandsTailingsConference,LouiseLake,AB:December7-10.

Kabwe, L.K.,Wilson, G.W., Scott, J.D., Donahue, R. and Lahaie, R. 2014. Field and laboratorymeasurements ofcentrifugecakedepositsforoilsandsreclamation.ProceedingsoftheCanadianGeotechnicalConference,Regina,SK.

Lipsett,M.,Olmedo,N., Rivard,B. andWilson,G.W.2014.Robotic systems formeasuringpropertiesof tailingsdeposits and collecting samples. Proceedings of the Fourth International Oil Sands Tailings Conference, LakeLouise,AB:December7-10,2014.

Olmedo, N. and Lipsett,M. 2014. Soil parameter estimation and sample collection using an unmanned groundvehicle.Proceedingsof theFourth InternationalOil SandsTailingsConference, LakeLouise,AB:December7-10,2014.

Olmedo,N.,Zhang,H.andLipsett,M.2014.Mobilerobotsystemarchitecture forpeopletrackingandfollowingapplications.IEEEInternationalConferenceonRoboticsandBiomimetics,Bali,Indonesia:December5-10,2014.


Pham, N.H. and Sego, D.C. 2014. Modeling Dewatering of Oil Sands Mature Fine Tailings Using Freeze Thaw.ProceedingsoftheFourthInternationalOilSandsTailingsConference,LakeLouise,AB:December7-10,2014.

Scott, J.D., Kabwe, L.K., Wilson, G.W. and Sorta, A. 2014. From Fluid to Solid: Oil Sands Fluid Fine Tailings.Proceedingsofthe7ICEGConference,Melbourne,Australia.

Slingerland,N.,Baida,M.andWilson,G.W.2014.Thegreatdividebetweenmineclosuregoalsandoutcomes,andpotentialsolutions.InFourie,A.,Tibbett,M.,(eds.).MineClosure2014.Proceedingsofthe9thInternationalMineClosureConference,Johannesburg,SouthAfrica:October1-3,2014.

Wilson,G.W,Kabwe,L.K.andScott,J.D.2014.Closureoptionsforoilsandsfluidfinetailingsponds.ProceedingsoftheInternationalMineClosureConference,Johannesburg,SouthAfrica.

Zhang, F., Fredlund, D.G.,Wilson, G.W. and Sedgwick, A. 2014. Determination of the permeability function fordryingoilsandstailingsundergoingvolumechangeanddesaturation.ProceedingsoftheFourthInternationalOilSandsTailingsConference,LakeLouise,AB:December7-10,2014.

Entezari, I., Rivard, B., Lipsett, M.G. and Wilson, G.W. 2013. Application of Hyperspectral Remote Sensing InEstimationofOilsandsTailingsWaterContent.IEEEWHISPERS2013,Gainesville,FL:June25-28,2013.

Entezari, I.,Rivard,B.,Lipsett,M.G.andWilson,G.W.2013.WaterContentEstimationofOilsandsTailingsUsingRemoteHyperspectralSensing.34thCanadianSymposiumonRemoteSensing,Victoria,BC:August27-29,2013.

Fredlund,D.G.andZhang,F.2013.Combinationof shrinkagecurveandsoil-water characteristic curves for soilsthatundergovolumechangeassoilsuctionisincreased.Proceedingsofthe18thInternationalConferenceonSoilMechanicsandGeotechnicalEngineering,Paris.

Kabwe,L.K.,Kone,M.,Sorta,A.,Wilson,G.W.,Scott,J.D.andUlrich,A.C.2013.Measurementsofunsaturatedsoilproperties of old and new mature fine tailings. Proceedings of the International Mine Closure Conference,Cornwall,UK.

Kabwe,L.K.,Scott,J.D.,Sorta,A.,Wilson,G.W.,Jeeravipoolvarn,S.andKone,S.2013.GeotechnicalCharacteristicsoftheMatureFineTailingsinthe30-Year10-mStandpipe.ProceedingsoftheCanadianGeotechnicalConference,Montreal,QC.

Kabwe,L.K.,Wilson,G.W.andDonahue,R.2013.DeterminationofGeotechnicalPropertiesofIn-LineFlocculatedFineFluidTailingsforOilSandsReclamation.ProceedingsoftheTailingsandMineWasteConference,Banff,AB:November3-6.

Olmedo, N. and Lipsett, M. 2013. Active soil parameter estimation using a UGV. Unmanned Systems CanadaConference,Vancouver,BC:November11-15,2013.

Scott, J.D., Kabwe, L.K., Wilson, G.W., Sorta, A. and Jeeravipoolvarn, S. 2013. Properties which affect theconsolidationbehaviourofMatureFineTailings.Proceedingsof theTailingsandMineWasteConference,Banff,AB:November3-6.


Reports&OtherPublications

Slingerland, N. 2018. Invited presentation to Northern Alberta Institute of Technology. Leduc, AB. GeologicalTechnologyProgram.April11.

Slingerland,N.,Schafer,H.,andEaton,T.2018.Long-termPerformanceofTailingsDamsinAlberta.GeotechnicalNews.March,2018.

Wilson,G.W.2018.TheNSERC/COSIAIndustrialResearchChairinOilSandsTailingsGeotechnique.PresentationattheCOSIAInnovationSummit,Calgary,AB:June7-8,2018.

McKenna,G.,Mann,V.,Fisseha,B.,Beier,N.andOlmedo,N.2017.Thistailingshastheconsistencyofchocolatepudding: a formal comparison of the geotechnical vane shear strength of food and soft tailings. GeotechnicalNews,35(1):28-33.

Wilson,G.W.2017.TheNSERC/COSIAIndustrialResearchChairinOilSandsTailingsGeotechnique.PresentationattheCOSIAInnovationSummit,Calgary,AB:March21-22,2017.

Brown,J.24January2016.CBCRadioInterview:The180.Seeingminesasblankcanvases.

Cairney,R.18January2016.PhDstudentwantsminingindustrytotakealong,long,longviewonimpact.UofANews.

Slingerland,N.2016.IntroductiontoMineReclamationforLandscapeArchitects.Invitedpresentation.UniversityofGuelph.LandscapeArchitectureDepartment.24October2016.

Slingerland, N. 2016. Geomorphic landform design for the Athabasca oil sands. Invited presentation. GolderAssociates.Mississauga,ON.26September2016.

Slingerland,N.2016.Landscapearchitecturalapproachtomineclosure. Invitedpresentation.GolderAssociates.Edmonton,AB.26April2016.

Slingerland, N. and Beier, N.A. 2016. An industry self-evaluation on geotechnical mine closure objectives andplanningteams.GeotechnicalNews.June2016.

Beier,N.2015.HowToImproveFluidFineTailingsManagementInOrderToEfficientlyIncreaseSolidsContentAndImproveTrafficabilityOfTheTailingsForReclamation.PresentationattheGlobalTailingsManagementCongress,Denver,CO:March17-18,2015.

Beier,N.2015.ResearchUpdatefortheNSERC/COSIAIndustrialResearchChairinOilSandsTailingsGeotechnique.PresentationtotheCOSIATailingsEPA,Calgary,AB:April20,2015.

Beier,N.A.,Sego,D.C.andMorgenstern,N.R.2015.Tailingsmanagementsimulationandtechnologyevaluation.GeotechnicalNews.33(3).

Slingerland,N.2015.LandscapeArchitectureandEngineeringDesignforMinedEarthStructuresandReclamation.Invitedpresentation.ShellCanada.Calgary,AB.19March2015.


Slingerland, N. 2015. The Architecture of Landforming for Mine Closure. Invited presentation. COSIA LandReclamationGroup.SyncrudeResearchFacility,Edmonton,AB.9January2015.

Slingerland, N., Landman, K. and Kelly, S. (2015, Nov). Post-mining landscapes as habitat conservation hubs?CanadianReclamation,15(2),18-22.

Wilson,G.W.2015.TheNSERC/COSIAIndustrialResearchChairinOilSandsTailingsGeotechnique.PresentationattheCOSIAInnovationSummit,Banff,AB:March31-April2,2015.

Cairney,R.2014.Gradstudents’startupcompanyismakingwaves,UofAEngineer.Fall2014issue.

Howell,D.2December2014.Transformingwaterscapes into landscapes focusofnewUofAresearchprogram.TheEdmontonJournal.

Olmedo, N. 2014. Poster presentation on IRC students’ research presentations at IOSTC 2014 for the ShellEnhancedLearningFundSymposium,Edmonton,AB:November17,2014.

Pratt,S.19November2014.UofA’s‘game-changing’sensorsrevolutionizemethodsofmonitoringclimatesciencedata.TheEdmontonJournal.

Slingerland,N.2014.LandscapeArchitecturalApproachtoMineClosure.Invitedpresentation.GolderAssociates.Burnaby,BC,andCalgary,AB.26-27November2014.

Slingerland,N.2014.WhyClosurePlansFail.Presentationatthe17thMiningIndustryLearningSeminar.SurfaceMiningAssociationResearchandTechnology(SMART).7October2014.

Slingerland,N.,Baida,M. andWilson,G.W.2014.New teams fornew schemes:Diversification inmine closure.CanadianReclamation,14(2):22-28.




PrincipalInvestigator:Dr.G.WardWilson


orJobTitle

DegreeStartDate

(ForStudentsOnly)


(ForStudentsOnly)

Dr.NicholasBeier UniversityofAlberta AssistantProfessor ChristineHereygers UniversityofAlberta ResearchTechnician Dr.LouisKabwe UniversityofAlberta ResearchAssociate Dr.MichaelLipsett UniversityofAlberta Professor Dr.BenoitRivard UniversityofAlberta Professor RalphBurden UniversityofAlberta PhDStudent 2014 2019KelseyCunningham UniversityofAlberta MScStudent 2016 2019JordanElias UniversityofAlberta MScStudent 2013 2018ImanEntezari UniversityofAlberta PhDStudent 2013 2016ImanEntezari UniversityofAlberta PostdoctoralFellow 2016 2017BereketFisseha UniversityofAlberta PhDStudent 2013 2019TaylorHall UniversityofAlberta MScStudent 2016 2019JaneenOgloza UniversityofAlberta MScStudent 2013 2017NicolasOlmedo UniversityofAlberta PhDStudent 2013 2019PrempehOwusu UniversityofAlberta MScStudent 2016 2019NamPham UniversityofAlberta PostdoctoralFellow 2013 2015UmmeRima UniversityofAlberta PhDStudent 2016 2020HaleySchafer UniversityofAlberta MScStudent 2015 2018NeeltjeSlingerland UniversityofAlberta PhDStudent 2014 2018ElenaZabolotnii UniversityofAlberta MEngStudent 2013 2016FeixiaZhang UniversityofAlberta PhDStudent 2013 2016FeixiaZhang UniversityofAlberta PostdoctoralFellow 2017 2019TonyZhang UniversityofAlberta MScStudent 2016 2019


ResearchCollaborators:


orJobTitle

Dr.DavidCarrierIII ArgilaEnterprisesInc. CEODr.RickChalaturnyk UniversityofAlberta ProfessorDr.DelwynFredlund UniversityofSaskatchewan ProfessorEmeritusDr.MurrayFredlund SoilVisionLtd. CEODr.DerekMartin UniversityofAlberta ProfessorDr.NorbertR.Morgenstern UniversityofAlberta DistinguishedUniversityProfessorEmeritusRichardNelson AlbertaInnovates ProgramDirector,OilSandsTailingsDr.LeonidasPerez-Estrada UniversityofAlberta AssistantProfessorDr.ArturoSanchez-Azofeifa UniversityofAlberta ProfessorDr.J.DonScott UniversityofAlberta ProfessorEmeritusDr.DaveSego UniversityofAlberta ProfessorEmeritusDr.PaulSimms CarletonUniversity ProfessorDr.DavidWilliams UniversityofQueensland Professor


ImpactofBitumenonTailingsConsolidationCOSIAProjectNumber:TE0027

ResearchProvider:SyncrudeCanadaLtd,UniversityofAlberta



Status:Ongoing

PROJECTSUMMARY

The impactof residualbitumenonthe long-termconsolidationbehaviourof fluid finetailings (FFT) isunknown.Thisunderstanding iscritical forthedevelopmentofnewFFTtreatmenttechnologies,aswellasoptimizationofcurrenttechnologies.Also,thisunderstandingisimportantformakingtherightdecisionswithrespecttotheneedforanyFFTpre-treatmentprior to treatmentanddeposition inorder toaccelerate thepaceof reclamation. Inaddition,forwater-cappedFFT,thisunderstandingisimportantforpredictingthelong-termsettlementtrajectoryoftheunderlyingFFTandassociated impactonwaterchemistryevolution. ThisprojectaimedatdevelopinganacceptablemethodologyformodifyingthebitumencontentsofaparentFFTandcharacterizingthemodifiedFFTsamplesintermsoflong-termconsolidationperformance.Pasteffortsaimedatmodifyingthebitumencontentsof a parent FFT prior to consolidation testing by using a solvent-wash procedure have been criticized due touncertaintiesrelatedtothelikelyimpactsonsurface/porechemistryandclaymineralogyoftheFFT.Thisprojectavoided the use of chemical amendments by developing a procedure for creating FFT samples with varyingbitumen contents (1.69%, 3.53% and 5.71%) from the same parent FFT. The FFT samples were self-weightconsolidatedusing the geotechnical beamcentrifuge at theUniversity ofAlberta for an approximateprototypetimeof35years.ThebitumenmodificationprocedurewaseffectiveincreatingFFTsampleswithvariablebitumencontentswiththesamekeyindexproperties(percentsolids,particlesizedistribution,etc.)fromaparentFFT.TheFFTsamplesexhibitedsimilarconsolidationperformancedespitetherangeofbitumencontents.Thisimpliesthatfortherangeofbitumencontentsandtheprototypetimesexamined,residualbitumencontentdidnotaffectthesettlement behaviour of FFT. Subsequent tests to further investigate if this trend holds for higher bitumencontent,variableFFTmineralogyandlongerconsolidationtimeframes,isplannedforthefuture.


A procedure for modifying the bitumen contents of the same parent FFT, without the use of chemicalamendments or solvent was successfully developed. The procedure involved adding variable amounts of abitumenfrothandprocesswatertotheparentFFTinordertocreatesampleshavingsimilarcomposition(physical,chemical and rheological),withbitumencontentbeing theonly variable. Characterizing theFFTpre- andpost-bitumenadditionconfirmedthatallkeyindexpropertiesoftheparentFFTremainedthesameafterthebitumen


contentmodification procedure. The long-term (35 years) consolidation performance of all three FFT samplesshowednodifferenceintermsofsettlementandporepressureevolution.

LESSONSLEARNED

Modifying the bitumen content of a parent FFT by using a methodology that does not introduce uncertaintyregarding the chemistry or mineralogy of the modified FFT is important in characterizing the long-termconsolidationbehaviourofFFT.Thiswassuccessfullyaccomplishedinthisstudy.Therewerenodifferencesintheconsolidation trajectoriesof themodifiedFFT samplesover the35years simulated in the current study. If thisobservationholdstrueforothertypesofFFTandforlongerconsolidationtimehorizons(beyond35years),thenabitumenremovalpre-treatmentstepforFFTpriortocommercialtreatmentmaynotbenecessary.Itisnotedthatbitumencontentshigherthan5.7%werenottestedinthecurrentstudy,andtheconclusionsfromthisstudymayormaynotbeextrapolatedtoFFTwithhigherbitumencontent.FuturestudiesassessingthefindingsinthisstudyonFFTsampleswithdifferentmineralogicalcompositionswillbeconducted.


Institution/Company:SyncrudeCanadaLtd.

PrincipalInvestigator:AdedejiDunmola


DegreeorJobTitle

DegreeStartDate

(ForStudentsOnly)


(ForStudentsOnly)

JimLorentz SyncrudeCanadaLtd. TeamLeader AdedejiDunmola SyncrudeCanadaLtd. GeotechnicalAssociate RandyMikula KaliumResearch Consultant GonzaloZambrano UniversityofAlberta ResearchAssociate RonSiman SyncrudeCanadaLtd. SeniorTechnologist MohamedAli SyncrudeCanadaLtd. Technologist RickChalaturnyk UniversityofAlberta Professor


AResearchTrajectoryTowardsImprovingFinesCapturePrediction–Verification,ApplicationandImprovementofDelft3DCOSIAProjectNumber:TE0028

ResearchProvider:Deltares



Status:Complete

PROJECTSUMMARY

Oil sands tailings are a dilutedmixture of sand, fines (solid particleswith a diameter of less than 44microns),residualbitumen(fromthebitumenextractionprocess),andprocesswater.Dependingonthetailingstreatmentprocess, tailings are transported to storage locations such as external (external to the mine pit) tailingscontainmentareas,deepdeposits,in-pit(oncetheoilsandsorehasbeenmined)tailingsareas,etc.Thesetailingscontainment areas or deposits, once reclaimed, will be part of the closure landscape after mining operationscease.Assuch,theabilitytoimprovethepredictioncapabilitiesofthedistributionofsandandfinesinatailingsdeposit—asa functionof tailingsdensities, sand-to-fines ratio (SFR),discharge rate, locationand time—offersacosteffectiveopportunitytooptimizecurrenttailingsmanagementoperationsandplanfortheclosurelandscape.

This project is the first phase of a multi-phase, multi-year research project that seeks to improve theunderstandingoftailingsandslurriesdepositionalflowbehaviourthroughmodellingto:

• optimizedepositionoperations;• minimizesegregationandproductionoffluidfinetailings(FFT)(i.e.,maximizefinescapture);and• supportthedesignofclosurelandscapeorlandreclamationprojects(totalsettlementandsettlement

rates,bearingcapacity).

Phase1oftheprojectincludes:

• areviewofCOSIAoilsandstailingsfinecapturedata;• areview,modificationandembeddingofrheologicalandsandsettlinganalyticalmodelsthatdescribe

depositionalflowandsandsettlingbehaviouroftailingsandsoftsedimentsintoanewDelft3D-Slurry(D3Ds)moduleofDelft3D.Delft3DisanopensourcenumericalmodeldevelopedandmaintainedbyDeltares.Delft3Disusedinhydrodynamic,sedimenttransportandwaterqualitystudiesworldwide;and


• theapplication(testing)ofthenewmoduletopredictoilsandstailingsflowbehaviourandsandsegregationforvariousrheologicalpropertiesandsand-to-finesratiosalongatypicaltailingsbeachcrosssectioninatwo-dimensional(2DV)configuration.

To minimize the production of fluid fine tailings (FFT), decrease water volumes, and accelerate tailingsconsolidationtimes,theoilsandsindustryistreatingFFTtoproducetailingswiththicknon-Newtonianbehaviour(i.e., flowbehaviourchangesas force isapplied). Delft3Dmodelsalluvialdeltaandbeaches inNewtonian flow,hencethedesiretoupgradeDelft3Dtosimulatespecificoilsandstailingscharacteristics.


Phase1activitieswerecompletedasplanned.Themainactivitiesandfindingsfromthisphaseoftheproject(toupgradeDelft3DtoD3Ds)included:

• analysisofdatafromCOSIA;• collectionandmodificationofrheologicalandsandsettlingmodels;• implementationandverificationofthemodelin1DV(one-dimensional)and2DV(two-dimensional);• comparisonofthe2DVmodelresultswithoilsandsdata;and• applicationofthe2DVmodeltoaspecificoilsandstailings.

ThisphaseoftheprojectdeliveredaD#Dsversionthatcanmodeltailingsdepositional flowandsandsettling in2DVmode,inaccordancewiththeoreticalexpectationsandlaboratoryobservations.Atthisstageofthemodel,itcanbeusedforageneralassessmentofdepositionalbehaviourofoilsandstailings.Additionalmodelverificationanddevelopmentisnecessary,however,tobringD3Dstoaquantitativeengineeringpredictivelevel.

Phase1producedtwoMSc.theses(Hanssen,2016andVanEs,2017),threeconferencepublicationsandaD3DsworkshopinCalgaryforCOSIAmembersandresearchers.

LESSONSLEARNED

Preliminaryresults fromtheprojectconfirmtheapplicabilityof thenewD3Dsmoduletooil sandstailings. Thefirstphasehighlightedtheneedforfurtherinvestigationtoaddressthefollowing:

• themodelissensitivetotherheology(flowcharacteristics)ofthetailingsmaterials(sand,finesconcentrationsandSFR);

• erosionorpick-upoftheagedorunderlyingtailingslayerbyfreshincomingflow;• mixingmechanismsbetweenthelayersandtheresultingrheologicalpropertiesifthetwolayersareof

differentinitialrheology;and• theroleofdensitystratificationversusyieldstresswhendeterminingmixingordisplacementofexisting

tailings.



PublishedTheses

Hanssen,J.L.J.2016.Towards improvingpredictionsofnon-NewtoniansettlingslurrieswithDelft3D: theoreticaldevelopmentandvalidationin1DV.Master’sthesis,DelftUniversityofTechnology.

Van Es, H.E. 2017. Development of a numerical model for dynamic depositioning of non-Newtonian slurries.Master’sthesis,DelftUniversityofTechnology.


Talmon,A.,VanRhee,C.,Winterwerp,H.,Hanssen, J.,Sittoni,L.2016. ImplementationofTailingsRheologyandTailingsSegregationinaPredictiveOpen-ChannelBeachingModel.Paste2016.19thInternationalSeminaronPasteandThickenedTailings.Santiago,Chile.July5-8,2016.

Sittoni,L.,Talmon,A.,Hanssen,J.,vanEs,H.,vanKester,J.,Uittenbogaard,R.,Winterwerp,J.,vanRhee,C.,2016.OptimizingTailingsDeposition toMaximizeFinesCapture: LatestAdvance inPredictiveModelling.PresentedatFifthInternationalOilSandsTailingsConference2016.LakeLouise,Canada.December4-7,2016.

Ansah-Sam,M.,Sheets,B.,Langseth,J.,Sittoni,L,Hanssen,J.2017.Delft3DModellingofSandPlacementonanOilSandsTreatedTailingsDeposit.PresentedatTailingsandMineWaste’17.Banff,Canada.November5-8,2017.


Institution:Deltares,DelftUniversityofTechnology

PrincipalInvestigator:Dr.ArnoTalmon


orJobTitle

DegreeStartDate

(ForStudentsOnly)

ExpectedDegreeCompletionDate

orYearCompleted

(ForStudentsOnly)

LucaSittoni Deltares ProjectManager

Dr.ArnoTalmon DeltaresPrincipalTechnicalInvestigator

JillHanssen DelftUniversityofTechnology MSc. 2016HugovanEs DelftUniversityofTechnology MSc. 2017Dr.CeesvanRhee DelftUniversityofTechnology Professor Dr.HanWinterwerp DelftUniversityofTechnology Professor


LimitationstotheGeotechnicalPropertiesofPolymer-TreatedFluidFineTailingsCOSIAProjectNumber:TE0030

ResearchProvider:SRKConsulting(Canada)Inc.



Status:Completed

PROJECTSUMMARY

Thebroadobjectivesofthisprojectweretocontributetotheunderstandingofwhatcanultimatelybeexpectedoftreated fluid fine tailings (FFT) in reclaimed mine landscapes and to provide insights leading to modified FFTmanagementmethods thatwill result in geotechnically-viablematerial. Oil sandsoperators currently treat FFTwithpolymerflocculants,followedbyinitialdewatering,thickening,centrifugationorair-drying.Theseprocessescanresultinsignificantincreasesinsolidscontent.However,thefurtherdevelopmentofpolymer-treatedFFTintogeotechnically-viablematerialremainsachallenge.

The project tested the following hypotheses: (1) there are fundamental limitations to the ability of polymer-treated FFT to consolidate, to drain or transmit water, and to gain strength; (2) these limitations are due tocolloidaland surfacechemistryeffectsassociatedwithFFT; (3) theadditionofpolymeras is currentlypractiseddoes not address surface chemistry effects and may even exacerbate the associated limitations; and (4) theadditionofbothcoagulantandpolymertoFFTcanproducematerialswithbettergeotechnicalproperties.Thefirstandfourthhypotheseswereconfirmed.Thesecondandthirdhypotheseswerefoundtobeprobablebutwerenotconfirmed.

Four FFT samples from two oil sands operators were tested. The initial samples were characterized for bothphysicalpropertiesandwaterchemistry.Subsampleswereamendedbyadditionofvariousamountsofinorganiccoagulant (MgSO4) and then flocculated with a polymer. The coagulant was selected to change the cationcompositionoftheFFTwaterandclaysurfaceswhilehavingaminimaleffectonpH,alkalinityorotherminerals.ThepolymerwasahighmolecularweightpolyacrylamideincommonuseforFFTtreatment.

Thetreatedandcontrolsampleswerethensubjectedtorangeofsettling,surfacepotentialandgeotechnicaltests.Specifically, the relationships between coagulant dosage, solids content, and undrained shear strength werecharacterized by fall cone testing of all treated and control samples. Selected sampleswere also subjected toseepageinducedconsolidationtests.Thetestresultswerethenusedasinputstoaseriesofconsolidationmodelstoexamineeffectsofthecoagulantonratesofdewateringandstrengthgain.


TreatmentofFFTwithacombinationofcoagulantandpolymer isexpectedto increaseporosity,compressibilityandhydraulicconductivity,allofwhichshouldleadtomorerapidconsolidationandstrengthgain.Thefindingsofthisstudywerenotconclusiveabouttheseeffects,largelybecauseofthelimitationsoftheconsolidationtesting.However,assessmentoftheremaininguncertaintiesshowedtheyarealleitherneutralorpositivewithrespecttoconsolidationandstrengthgainfortreatedFFT.


FindingsshowthatFFTtreatedwithbothcoagulantandpolymerstarttogainstrengthata lowersolidscontentcomparedtopolymer-treatedFFT,andcontinuestodisplayhigherstrengthasthesolidscontentfurtherincreases.Inverypracticalterms,improvingFFTstrengthbytreatmentwithbothcoagulantandpolymermeansthatFFTcanbereadyforreclamationintimesthatare10%to30%lessthanthoseneededforFFTtreatedwithpolymeronly.

Thetestingprogramandmodellingwerecompletedin2017andtheprojectreportwasfinalizedin2018.

LESSONSLEARNED

The results of thiswork confirm that treating FFTwith a combination of coagulant and polymer leads tomorerapidstrengthgain,andthereforecouldacceleratefinalreclamationoftreatedFFTdeposits. Thecoagulantanddosages chosen for thisprojectwereasmildaspossible toavoidany confounding chemical reactions; strongercoagulantsmayhavemoresignificanteffectsonFFTstrengthgain.Thelaboratorytestmethodsdevelopedinthisstudyprovidearelativelyrapidmeanstoscreenawiderangeofadditivesanddosages.



D. Hockley & H. Rourke 2018. Limitations to the Geotechnical Properties of Polymer-Amended Tailings,Presentationto2018OilSandsInnovationSummit,Calgary,June2018.


SRK Consulting (Canada) Inc. 2018. Limitations to the Geotechnical Properties of Polymer-Treated FFT, Report1CC047.001prepared forCanada’sOilSands InnovationAlliance (COSIA)TailingsResearchWorkingGroup,April2018.



Institution:SRKConsulting(Canada)Inc.

PrincipalInvestigator:DarylHockley,P.Eng.


orJobTitle

DegreeStartDate

(ForStudentsOnly)


(ForStudentsOnly)

HollyWilliams(Rourke) SRKConsulting(Canada)Inc. JordanElias NRCanDevonResearchCentre CraigMcMullen NRCanDevonResearchCentre


TailingsConsolidationMechanismsCOSIAProjectNumber:TE0031,RWG(IOSI2015-05)

ResearchProvider:UniversityofCalgary


IndustryCollaborators:Imperial,SuncorEnergyInc.,SyncrudeCanadaLtd.TeckResourcesLimited

Status:Completed

PROJECTSUMMARY

Theoilsandsbitumenextractionprocessgenerates largevolumeoftailings,consistingofamatrixofsand,clay,water,andfineparticlesbelow44µm(Bogeretal.2013). Inatailingspond,partialsettlementofcoarsesolidsleadstotheformationofmaturefinetailings(MFT).MFTgenerallyconsistsof30wt%fineclay,60wt%to70wt%water,andmostlywith1wt%-5wt%residualbitumen.Withouttreatment,MFTmaytakeupto150yearstofullydewaterandsettleout.AsofAugust2012,approximately800millionm3offluidtailingswereheldinabove-gradecontainmentdams(OSTCandCOSIA2012). Managing,stewardingandlimitingtheaccumulationoffluidtailingsareconsistentwiththegoalsofprogressivereclamationandclosure(OSTCandCOSIA2012),aswellasdecreasingliabilityandenvironmentalriskresultingfromtheaccumulationoffluidtailingsonthelandscape.

ThisprojectexaminedtailingsconsolidationmechanismsthroughacombinationofX-raycomputedtomography(CT), nuclear magnetic resonance spectroscopy (NMR and one-dimensional [1-D] magnetic resonance imaging[MRI]),anddielectricpropertiesmeasurementsthroughelectromagnetic(EM)sweeps.

Themajorobjectivesincluded:

1) ToscreenthepotentialforCT,NMR,1DMRI,EMtocharacterizesettlingpropertiesoforiginal(unsettledanduntreated)MFT.

2) Tocharacterize raw (untreatedbychemicaladditives suchas flocculantsor coagulants)MFTby severalanalyticaltechniques:Dean-Starkextraction,methyleneblueindex(MBI),particlesizedistribution(PSD,)andwaterchemistry.

3) ToutilizeCT,NMR,1-DMRI,andEMtechnologiestocharacterizerawMFTandtreatedMFTsamples.4) Todevelop testprotocolsand technology that canbeused to characterize the settlingand transitional

stagesoforiginalMFT.5) Todevelopamodellingapproachforthesettlementbehavioursofrawtailingsandtreatedtailings.

Measurements were taken for original untreated, and treated with flocculant and coagulant additives MFTsamples from two sources. UntreatedMFT sampleswere considered as control cases. CT, NMR,MRI and EMtechniqueswereusedintheexperiments.CTmeasurementsarebasedondensityprofiles,whileNMRisbasedonamplitudesandrelaxationtimesoffreewaterandboundwater.WhiletheCTandNMRmeasurementtechniquesare completely independent,bothwereable tomeasurea similar rate (±0.5%)of freewaterphase separation


over time,and thicknessof thewaterphaseover time. This is significantbecause ifonly theNMRsystemwasavailablewhenmonitoringMFTsettlement,thedatawouldbeexpectedtobesimilartousingCT.

Thedataofporosityversusdepthand locationwereused inmodellingtopredictthesettlingrateofanoriginalMFToveralongerperiodoftime,andtopredictthepermeabilityoftheMFTregionovertime.

ThecharacterizationofrawMFTpropertieswascarriedouttodeterminewatercontent,solidscontent,particlesizedistribution,MBI, andpropertiesofMFTprocesswater. It shouldbenoted that theMFTpropertiesare inagreementwithexperimentalresultsfromCT,NMR,andMRI.Forexample,thesoliddensityat2.650g/cm3andwatercontentandsolidscontentareconsistentwiththedensityprofileofMFTfromCTmeasurement.

In the secondphase,experimentalwork replicated thesemeasurements in treatedMFTsamples,and the sameoutput parameters were acquired and compared against the original MFT. During the investigation, it wasobserved that treatmentwith a polymer flocculantwasmore effective compared to the sole use of coagulant.Combinedcoagulantandflocculantadditives (Malikova,etal.2016)areabletobothsignificantlyacceleratethesettlingbehaviouraswellasdecreasewatercontentinthefinalsettledmaterial.

Finally,theresultsoftheexperimentswereanalyzedusingkineticreactionand1-Dspatialparticlemodels. TheratesandultimatedilutionparametersfortheMFTsampleswereestimatedusingstatisticalanalysisofthedata.The estimated parameters can be used for both simulating settlement behaviour and evaluating the additiveefficiency. One-dimensionalspatialparticlesettlingmodelswereusedforestimatingspatialsettlingparametersandsimulatingMFTsettlementbehaviour.

Theresultsofthemeasurementsareverysignificantforindustrialapplications.Firstly,measurementproceduresweredevelopedforevaluatingMFTsettlementusingx-rayCT,NMRandMRI(Kantzas1994,Wright,etal.2004,MottaCabreraetal.2009,MottaCabrera,etal.2010,Manalo,etal.2003,Kantzas,2003,HumandKantzas,2007).It was shown that all three approaches are able to evaluate settling behaviour and provide statistically similarconclusions. Thisobservation is very important fordevelopingefficient field settlementmonitoringequipment.NMRisthebestcandidateforsuchequipmentduetoitsrelativelowcost,fastmeasurementsandthepossibilityofon-linedataprocessing.Ontheotherhand,x-rayCTisamoreappropriatelaboratorymeasurementtechniquethat is capable of providing information about two-dimensional (2-D) density distribution of MFT samples.However,thistechniqueismoreexpensiveanddifficulttoimplementunderfieldconditions.

Secondly,theexperimentsenableddevelopmentofaworkflowforevaluatingandanalyzingtheeffectofdifferentadditives on the settling behaviour of MFT samples. This workflow could be very important for industrialapplicationswhenestimating theoptimumconcentrationsofdifferent additives. Suchestimation is possible inlaboratory conditions using relatively smallMFT samples. The examplewith coagulant and flocculant additivesillustratesthe importanceofsuchanalysis. Inthecaseoftheadditives,thecombinedtreatmentprovidesbettersettlingbehaviourfortwocriteria,includingtherateofsettlementandtheamountofresidualwaterinthesettledsamples.

Finally, themodellingapproachesdevelopedandapplied in thisprojectmake itpossible toestimatesettlementparametersaswellastosimulatesettlement.


Theapplicationoftheresearchresultsintomineandtailingsmanagementplanswouldrequiretwomajorstages;includinglaboratoryestimatesoftheoptimumconcentrationsofadditivesfortailingsamples,andfieldmonitoringofsettlementusingoptimumtreatments.


Theprojectwork iscompleted. Allobjectivesof theprojectareachieved. Summaryofprojectachievements ispresentedintheprevioussection.

LESSONSLEARNED

X-ray CT, NMR, MRI and EM techniques are effective monitoring approaches for evaluating MFT settlementbehaviour.Thesetechniquesprovideconsistentresultsforoptimizingtailingpondtreatmentswithcoagulantandflocculantadditives.EstimatingtheoptimumconcentrationofadditivesisnecessaryforefficientandeconomicalMFT settlement. Both coagulant and flocculant additives are required for optimum settling treatment.Concentrationsoftheseadditivesarefielddependentbutcanbeestimatedinlaboratoryconditionsusingoneofthedevelopedtechniques.FieldmonitoringcanbeconductedusingtheNMRon-linetool.

LITERATURECITED

Boger,D.V.RheologyofSlurriesandEnvironmentalImpactsintheMiningIndustry.AnnualReviewofChemicalandBiomolecularEngineering4,239-257,2013.

Hripko, R., Vajihinejad, V., Motta, F.L., Soares, J.B.P. Global Challenges 2, 1700135, 2018.https://onlinelibrary.wiley.com/doi/pdf/10.1002/gch2.201700135

Malikova,P.,Thomas,J.,Chromikova,J.,Vidlar,J.,Kupka,J.PerspectivesinScience7,171-177,2016.

Kantzas, A., "Computation of Holdups in Fluidized Beds and Trickle Beds by Computer Assisted Tomography",A.I.Ch.E.J.,40(7),1254-1261,1994.

Wright,I.,Lastockin,D.,Allsopp,K.,Evers-Dakers,M.E.andKantzas,A.,“FieldTrialsofaLowFieldNMRWaterCutMeteringDevice”,CIM2002-194(Note),J.Can.Pet.Tech.,43(5),17-21,2004.

MottaCabrera,S.C.,Bryan,J.,Komishke,B.andKantzas,A.,“StudyoftheSettlingCharacteristicsofTailingsUsingNuclearMagnetic Resonance (NMR) Technique”, International Journal ofMining Reclamation and Environment,23(1),33-50,2009.

MottaCabrera, S.C., Bryan, J. andKantzas,A., “EstimationofBitumenand SolidsContent in Fine TailingsUsingLow-FieldNMRTechnique”,CIPC2007-074,SPE138973,J.Can.Pet.Tech.,49(7),8-19,2010.

Manalo, F.P., Lastockin, D., Bryan, J. and Kantzas, A., “Using NMR Spectra to Determine Compositions ofUnconsolidatedSand/Clay/Brine/HeavyOilSamples”,presentedatthe2003InternationalSymposiumoftheSocietyofCoreAnalysts,heldinPau,France,September21-24,2003.


Kantzas, A., "Investigation of Physical Properties of Porous Rocks and Fluid Flow Phenomena in PorousMediaUsingComputerAssistedTomography",InSitu,14(1),77-132,1990.

Hum, F.P. and Kantzas, A., “Clarifying the Contribution of Clay BoundWater and HeavyOil to NMR Spectra ofUnconsolidatedSamples”,CIM2003-100,J.Can.Pet.Tech.,46(7),30-36,2007.

OilSandsTailingsConsortium(OSTC)andCanada’sOilSandsInnovationAlliance(COSIA).2012.TechnicalGuideforFluidFineTailingsManagement.


JournalPublications

Twojournalpublicationsareinpreparation.


Babak, P., Kantzas, A., Li, F., Motta, S. 2018. Laboratory and Field Monitoring of Efficiency of Flocculant andCoagulant Additives on Settling Behaviour in Solid Liquid Suspensions. Suncor Academic Forum onTransformationalTechnologyforEnergySystems.October10-12,2018.

Babak, P., Kryutchkov, S., Bryan, J., Kantzas, A. 2017. Tailings consolidationmechanisms. Institute forOil SandsInnovation(IOSI)May10-11,2017Stewardship.Edmonton,Canada.


Institution:UniversityofCalgary

PrincipalInvestigator:ProfessorApostolosKantzas


orJobTitle

DegreeStartDate

(ForStudentsOnly)


(ForStudentsOnly)

ApostolosKantzasUniversityofCalgary,PERMInc. Ph.D.,Professor

PetroBabak UniversityofCalgaryPh.D.,ResearchAssociate

FengLi PERMInc. Ph.D.Researcher


InSituRealTimeMeasurementsofSolidsContentinSettlingTailingsCOSIAProjectNumber:TE0041

ResearchProvider:UniversityofAlberta,NAIT


IndustryCollaborators:SyncrudeCanadaLtd.,SuncorEnergyInc.,Imperial,TeckResourcesLimited

Status:Year1of3

PROJECTSUMMARY

Theobjectiveofthisprojectistodevelopasubsurfacesolidscontentanalyzerbasedonhybridopticalandsafex-raymethods. Various options will be explored for both techniques, including different wavelength lasers anddetection geometries for the optical technique and different sources and geometries for the low level x-raydetector.Thex-raytechniquewillbeusedasthecalibrationstandardfortheopticalsensors.Thetechnologywillbevalidated in laboratoryscalesystems. Numericalmodelswillbedeveloped forboth thescatteringandx-raymeasurementtechniquestoalloweasyextensiontosystemswithdifferentmaterialconstituents.Thetechnologywillbedevelopedinsuchawaythatitcanbeimplementedatremoteoilsandstailingpondstomeasuresettlingoftailings in real time with lateral and depth spatial resolutions. This technology can be used by the oil sandsindustrytoincorporateintothedesignoftheiroilsandsprojectstodeliveramoreeffectiveprocessandimprovedenvironmentalperformance.

Milestonesinclude:

1. Testingofscatteringtechniqueswithsimpleclaysinsuspensionsuchaskaolinite.2. TestingofscatteringtechniqueswithFFTsamples.3. Developmentofalowactivityx-raysourceanddemonstrationofabilitytomeasuresolidscontent.4. Implementationofalowactivityx-raysourceinageometryanddetectorsystemsuitableforinstallation

intestcolumns.5. Investigation of window fouling and development of strategies to mitigate effects on scattering

measurements.6. Optimization and demonstration of optical measurements of settling using an array of scattered light

detectorsintestcolumnswithfluidfinetailings(FFT)samples.7. Demonstrationoflowlevelx-raymeasurementsintestcolumnswithFFTsamples.8. Demonstrationofcalibrationofopticalscatteringdetectorswithlowlevelx-raydetectorsintestcolumns.9. DevelopamodellingcodeforlightscatteringfromkaoliniteandFFT.10. Developamodellingcodeforx-raytransmissionthroughkaoliniteandFFT.



Thisisthefirstyearofreportingonresults.Theresultstodateinclude:

1. Labbenchmeasurementsofthescatteringoflaserlightatvariousanglesandatvariouswavelengthshavebeencarriedout.

2. Atestcolumnanddetectormountingtubehasbeendeveloped.3. Scatteringmeasurementsofthesettlingoftailingsinatestcolumnhavebeenstartedoverperiodsofup

toonemonth.4. Foulingtestshavebeencarriedoutonvariousplasticandglasswindows.5. TheabilitytomeasureinorganicsolidscontentintestsamplesofkaoliniteandFFThasbeen

demonstratedusingalowlevelx-raysource.6. Thedevelopmentofafirstprinciplesmodellingcodehasbeenstartedusing3DFiniteDifferenceTime

Domain(FDTD)ElectromagneticScatteringcalculationstomodelthescatteredlightfromonetoafewirregularshapedparticles.

7. AfirstprinciplesmodellingcodebasedonGEANT4hasbeendevelopedforthelowlevelx-rayscatteringmeasurementsandcomparedtothemeasurementsobtainedinkaoliniteandFFT.

LESSONSLEARNED

Thelessonslearnedthusfarinclude:

1. Thescattered lightversusangle fromkaolinite samplesbehave toa largeextentasadiffuse scatteringmedium.

2. Preliminary measurements of the dependency of scattered light versus wavelength from FFT samplesindicatebothshortwavelengthandlongwavesourcesareadvantageousfordetectionofsolidscontent.

3. It is possible tomonitor solids settling in a test columnmeasuring backscattered lightwith amultipledetectorarray.

4. Accuratemeasurementofsolidscontentcanbemadewithlowlevelx-raytransmissiondiagnostics.5. Modellingofx-raydiagnosticresponserequiresincorporationofbothabsorptionandscatteringinthex-

raymodel.



PriyeshDhandharia,WeiWang,YuWan,BoYu,AndreaSedgwick,AbuJunaid,R.Fedosejevs,ManishaGupta,andYingY.Tsui.2018.“OpticalScatteringTechniquetoMonitorSolidsContentinFluidFineTailings(FFT)”,presentedat the 6th International Oil Sands Tailings Conference (IOSTC), December 9-12, 2018, Edmonton, Alberta.(PresentationandWrittenConferenceProceedingsReport)

Bo Yu, Wei Wang, Felipe Goncalves, Priyesh Dhandharia, Andrea Sedgwick, Abu Junaid, Manisha Gupta, R.FedosejevsandY.Y.Tsui.2018.“Measuring Solids Content in Fluid Fine Tailings (FFT) Using a Low-Level X-ray


Radiation Source”, presented at the 6th International Oil Sands Tailings Conference (IOSTC), December 9-12,2018,Edmonton,Alberta.(PresentationandWrittenConferenceProceedingsReport)


R. Fedosejevs, Y.Y. Tsui,M. Gupta and A. Sedgwick. 2018. “Technology for In-situ Real TimeMeasurements ofSolidsContentinSettlingTailings“,PresentedattheCOSIATailingsProjectDisseminationReview,November15,2018,Calgary,Alberta.



PrincipalInvestigator:YingY.Tsui


orJobTitle

DegreeStartDate

(ForStudentsOnly)


(ForStudentsOnly)

ManishaGupta UniversityofAlberta Assist.Professor

AndreaSedgwickNorthernAlbertaInstituteofTechnology

AppliedResearchChair

RobertFedosejevs UniversityofAlberta Professor FelipeGoncalves UniversityofAlberta UndergradStudent 2015 2019YuWan UniversityofAlberta MScstudent 2016 2018PriyeshDhandharia UniversityofAlberta PostDoctoralFellow BoYu UniversityofAlberta MScStudent 2017 2019WeiWang UniversityofAlberta MScStudent 2017 2019

ResearchCollaborators:NSERC


ConversionofOilSandsBy-productstoClosureLandformsCOSIAProjectNumber:TE0045

ResearchProvider:McKennaGeotechnicalInc.andBGCEngineeringInc.


IndustryCollaborators:SyncrudeCanadaLtd.,TeckResourcesLimited,Imperial,CanadianNaturalResourcesLimited

Status:Year1of2

PROJECTSUMMARY

Oilsandsoperationsproduceseveraltypesofby-products,someofwhichneedtobeusedtoconstructpermanentlandforms thatmust integrate into the final closure landscape and support a self-sustaining, boreal ecosystem.Typically,thesematerialsareplacedinlocation-specific,designedstoragefacilitiesorrepositoriesthatmayeitherbetemporaryorpermanent.

Theobjectiveofthisprojectistoobtainanddocumentenvironmentalinformationonminingby-productsfortheiruseintheselectionanddesignoflandformsandlandformelementsintheclosurelandscape.Thiswillbedoneforeach operatorwhile highlighting any geotechnical or geo-environmental issues related to handling or long-termstorage.

TheprojectisacollaborativeeffortofCOSIA’sTailingsEnvironmentalPriorityArea(EPA)andLandEPA.PhaseIandPhaseIIwillbeledbytheTailingsEPA.Theprojectincludes:

• asystematicreviewofkeyby-productsfromtheoperations(PhaseI);• examiningtheirpropertiesthroughdevelopedtestingstandards(PhasesIandII);and• analysing their suitability for placement in standard landform structures such as overburden structures,

stockpiles,specializedcontainmentareaswithinoverburdenstructures(i.e.,slopcells)(PhaseIII).

The finaldocument (Phase III)will bea technical guideline identifyingbestpractices formaterial evaluationanddesign analysis, general suitability analysis of major by-products for placement in standard landforms, andrecommendationsandidentificationoffurtheropportunitiestorefinethebestpracticebasis.


ThemajorityofPhaseIworkwascompletedin2018.Alistofby-productsproducedduringsurfaceminingatthevariousoilsandsoperationswascompiled.Thelistincludedmaterialssuchasgypsum,flyash,andfrothtreatmenttailings.Amethodologywasalsodevelopedtosystematicallycharacterizethegeotechnicalandgeo-environmentalproperties of the by-products to inform the assessment of landform conversion; that is, the progression from


standard to closure landforms. Data from the oil sands operators were assessed to determine if sufficientinformationwasavailabletocharacterizetheirby-productsforlandformconversion,orifsamplingandlaboratorytestingarerequiredtoaddressthedatagaps.Thislatterworkwillbecompletedin2019.

Projectparticipantsidentifiedanewconcept,adaptivelandform,asapotentiallynewtypeoflandformthatwillbedefinedandexploredinPhaseII.

LESSONSLEARNED

Thisprojectisinitsearlystagesandtherefore,resultsaretoopreliminarytobeincludedaslessonslearned.Thisworkwillformanimportantreferenceforplannersandengineerstaskedwiththedesignandstorageofoilsandsby-products. Theprimaryusewillbe forCOSIAoperatingmembers. Anypublic releasewill require reviewandapprovalbyCOSIAmembersasaseparateactivity.


PrincipalInvestigators:McKennaEngineeringInc.andBGCEngineeringInc.


PlanningandDesignofDeepCohesiveTailingsDepositGuideCOSIAProjectNumber:TE0046

ResearchProvider:McKennaGeotechnicalInc.


IndustryCollaborators:CanadianNaturalResourcesLimited,SuncorEnergyInc.,SyncrudeCanadaLtd.,TeckResourcesLimited

Status:Year1of2

PROJECTSUMMARY

ThemandateofCOSIA’sDeepDepositandSoftDepositCappingWorkingGroup(DDWG)istoidentifyanddevelopapproachesandtechnologiesfordesigningandimplementingdeepcohesivedepositsintheoilsandsandexploredifferenttypesofcappingstrategiestothedepositsinatimelymannertoaterrestriallandform(withwetlands).Deep cohesive tailings deposits are fines-dominated cohesive materials with associated depositional andconsolidation behaviour that is considered an appropriate tailings management approach for mines wheredisposalareasandstoragevolumesareavailable(typicallyin-pit).Adepositisformedbycontinuousdischargeoftreated/reprocessedfluidfinetailings(FFT)intoin-pitdisposalsitesbetween20and140metres(m)thick.

Aguidedescribingthetechnicalrequirements,activitiesandprocessflowsneededtodevelopandexecuteadeepdeposit from design through to capping, consistent with the requirements of the desired closure landforms isunderdevelopment as part of theDDWGmandate. Theproposed guidewill use existingdata, experience andknowledgetodescribethecurrentstateofpracticefordeepcohesivetailingsdeposits intheoilsandsandtheirexpectedperformanceduringdesign,placement,reclamationandclosure. Theguidewillbeatechnicalmanualand reference formineand tailingsplanners, geotechnical engineers, technical specialists and closure landformdesignteams.


Workontheprojectcommencedin2018withpreparingaworkplan,assemblingrelevanttechnicalandprocessinputs, and beginning the task of drafting the guide. Workwas about 50% complete at the end of 2018withcompletion targeted for the firsthalfof2019. Acommunicationand implementationplanwillbedeveloped inconjunctionwithguidepreparationandcompletion.

Theguideisacompendiumofdeepdepositplanning,placement,management,andreclamationknowledgeandexperienceaccumulatedthroughseveraldecadesbytheoilsands industry. TwoCOSIAworkshops inparticular:the2017DeepDepositCappingWorkshop;andthe2018DeepDepositConsolidationWorkshopprovidedvaluable


casehistories,researchdata,anddesigninformationthatformthebasisoftheguide.Awealthofotheroilsandsandinternationalliteratureaugmentsinformationfromtheworkshops.

LESSONSLEARNED

Theprojectwasinitiatedin2017withatargetcompletiondatein2019;thereforeitistoopreliminarytopresentlessonslearned.

Observationsandknowledgefromtheaccumulateddesign,researchandexecutioneffortondeepdepositsintheoilsands,includinganassessmentofgapsandopportunitiesforadditionalresearchandinvestigation,areplannedfor inclusion in theguide. Guidance in theapplicationanduseofdeepcohesivedeposits inminingand tailingsplanningschemesisincluded.

LITERATURECITED

Therewillbeseveralhundredreferencescited inthecompletedguide includingpreviouslyunpublishedresearchdataandinformation,andcasehistorydocuments.


Institution:McKennaGeotechnicalInc.

PrincipalInvestigator:GordonMcKenna


orJobTitle

DegreeStartDate

(ForStudentsOnly)


(ForStudentsOnly)

GordonMcKenna McKennaGeotechnicalInc. GeotechnicalEngineer DavidWylynko WestHawkAssociates Communications JamesHrynyshyn WestHawkAssociates Communications JunePollard JPollardConsulting EngineeringGeologist BillShaw WHSEngineering TailingsEngineer DerrillShuttleworth N/A Illustrator


EffectsofShearingonDewateringandCompressibilityofTreatedTailingsCOSIAProjectNumber:TE0058


IndustryChampion:SuncorEnergyInc.,Imperial,CanadianNaturalResourcesLimited

IndustryCollaborators:SyncrudeCanadaLtd.,TeckResourcesLimited

Status:Year1of1

PROJECTSUMMARY

The ultimate goal of treating oil sands tailings is to remove water within a reasonable time frame to enablereclamation and closure. Several technologies have been proposed for dewatering of tailings includingflocculation,filtration,centrifugation,thickening,atmosphericdrying,andsedimentation.Manyofthetreatmentmethodsinvolvetheadditionofpolymericflocculantsandsubsequenttransporttodepositionsitesusingpipelinetransportsystems.

Treatedtailingsexperiencearangeofshearconditionsduringtransportanddeposition.Itisgenerallypresumedthatshearingadverselyaffectsthewaterreleaseandcompressibilityoftreatedtailings.Accordingly,shearrateisconsideredaconstraintwhendesigningprocessingequipment,pipelines,anddepositionstrategiesusedintailingstreatment facilities. Apreliminary studywasconductedonmeasuring thepipelining impactondewateringandmaterialstrengthofflocculatedfinetailingsatCoandausingaCouettedevicetomimictheshearingconditions[1].However,despiteitsimportance,theeffectsofshearingondewateringandlong-termconsolidationcharacteristicsof treated tailings have not been studied in detail. Additionally, the impact of processing variables such asflocculanttype,dosage,andmixingconditionsontheshear-dewateringrelationshipisnotfullyunderstood.

This project aims to study these effects through a series of laboratory experiments on two selected types oftailings:fluidfinetailingsandthickenedtailings.Flocculantswereblendedwiththetailingsusinganin-linepipemixer and characterized before undergoing varying levels of shear in a custom shear-cell. Additionalcharacterization measurements were performed post-shear and samples are undergoing geotechnical testing,includinglargestrainconsolidation,seepage-inducedconsolidation,andbeamcentrifugation.Thedatacollectedfromtheexperimentswillbeusedtomodeltheconsolidationbehaviourofthesamplesatfieldscale,providingalinkbetweenpipelineshearconditionsanddepositperformance.


The project is still in progress and final results are not yet available. All of the flocculation experimentswerecompletedin2018andthematerialsarenowundergoinggeotechnicaltesting.


Thematerialsproducedinthelaboratorywithvaryinglevelsofshearhaddifferentpropertiesthatwerequantifiedthroughvariousmetrics.Asexpected,shearingreducedtheyieldstrengthofthematerialinallcases,butundersomeconditions, low levelsofpost-flocculation shearingappeared to improvedewatering characteristics. Highlevelsofshearhadanimpactontheimmediatematerialperformance,butlong-termperformanceremainstobequantified. Some initial results suggest minimal impact on the compressibility of some samples, with smalldifferencesinpermeabilitynotedathighervoidratios.

Thefinalresultsavailable in2019willprovide insight intotheeffectsofshearontreatedtailingscharacteristics,allowingoperatorstotailortreatmentstrategiestotheirparticularrequirements.

LESSONSLEARNED

Experimentsarestillinprogresssoitistooearlytodiscusslessonslearned.

LITERATURECITED

[1] EffectsofShearingandShearingTimeonDewateringandYieldCharacteristicsofOilSandsFlocculatedFineTailings, Babak Derakhshandeh, Abu Junaid and Gavin Freeman. 2016. International Oil Sands TailingsConferenceProceedings,LakeLouise:December2016.



Institution:CoandaResearch&DevelopmentCorporation

PrincipalInvestigator:ScottWebster,ClaraGomez(onleave)


orJobTitle

DegreeStartDate

(ForStudentsOnly)


(ForStudentsOnly)

ScottWebsterCoandaResearch&DevelopmentCorporation ResearchScientist

ClaraGomez CoandaResearch&DevelopmentCorporation ResearchScientist

AmarebhSorta CoandaResearch&DevelopmentCorporation

GeotechnicalEngineer

TayfunAydinCoandaResearch&DevelopmentCorporation ResearchScientist

PravicKomalCoandaResearch&DevelopmentCorporation LaboratoryTech

MarianaCruzCoandaResearch&DevelopmentCorporation LaboratoryTech

AshleyGonzalezCoandaResearch&DevelopmentCorporation LaboratoryTech


SoftSoilSettlementandStrengthasAppliedtoOilSandsFineTailingsCOSIAProjectNumber:TE0077andTX0131

ResearchProvider:ArgilaEnterprisesInc.

IndustryChampion:CanadianNaturalResourcesLimited(CanadianNatural)


Status:Year2of2

PROJECTSUMMARY

Thepurposeof thisproject is todocumentpreviousefforts,experienceandunderstandingofconsolidationandsettlementanalysesofsoftsoilasappliedtofinetailingsintheoilsands.Thedevelopmentofthedocumentwasinitiatedthroughvariouscorrespondenceandreportssupportingseveraloilsandstailingspilotsbetween2013and2016atShellCanada(nowCanadianNatural),buildingoffofpreviousworkbyDr.CarrierofArgilaEnterprises,Inc.intheoilsandsasearlyasthe1980sandatothermines.Activedevelopmentandpreparationofthedocumentwasstartedin2017andcompletedin2018.

Theresultingdocumentprovidesanoverviewofconsolidationtheoryandpractice,withpracticalexplanations,tohelpusersunderstandthefundamentalconceptsthatareoftencloudedbyeasy-to-usecomputerprograms.Thegoal of the guide is to clarify and bring greater consistency, accuracy and repeatability to consolidationassessmentsandsettlementcalculationsofdeepcohesivetailingsdepositsintheoilsands.

The contents of the documentwere applied to develop a relatively easy-to-useMicrosoft Excel spreadsheet tocalculateconsolidationandsettlement.TheguideandspreadsheetformedthebasisofaConsolidationWorkshop(March 2018) attended by COSIAmember company employees and research partners. The documentmay beupdatedperiodicallytoincluderesearchadvancesandreviewfeedback,asappropriate.


The guide and workshop were structured to promote greater consistency, accuracy and repeatability ofconsolidation and settlement calculations and evaluations for deep cohesive deposits in the oil sands. Theknowledgeandbenefitsoftheguideandtheworkshopwere:

• Review sedimentation and consolidation theory for deep tailings deposits (>2 m) and summarizesedimentation,consolidationandinputfunctionstothemodel.


• Interpretcompressibilityandhydraulicconductivityfunctions,andreviewstrengthandtheimportanceofinputfunctions.

• Greaterconsistency,accuracyandrepeatability incalculatingthefinalsettlementofdeepdepositswithaneasy-to-useMicrosoftExcelspreadsheet.

• Interpret results using case histories and more recent data and information from tailings researchinitiativesandprojects.

• Each company received copies of the guide and the Microsoft Excel spreadsheet for calculating andassessingconsolidationandsettlementofdeepcohesivedeposits.

LESSONSLEARNED

The document and spreadsheet are based on generally accepted geotechnical formulae and principles ofconsolidation theory, case histories and research information. They provide systematic guidance in estimatingconsolidationandsettlementofdeepcohesivedepositsinminingandtailingsplanningschemes.Thedocument,proceduresandspreadsheetbringgreaterconsistency,accuracyandrepeatabilitytoconsolidationandsettlementestimates in the oil sands. The guide provides insight into various input parameters, calculationmethodology,expectedresultsandtheimplicationsofconsolidationsettlementfortailingsplansandtailingsplanning.


Institution:ArgilaEnterprises,Inc.

PrincipalInvestigator:DavidCarrier


orJobTitle

DegreeStartDate

(ForStudentsOnly)


(ForStudentsOnly)

DavidCarrier ArgilaEnterprises,Inc. GeotechnicalEngineer RobertMahood Imperial TechnicalSupport

MonicaAnsah-SamCanadianNaturalResourcesLimited TechnicalSupport

GavinFreemanCanadianNaturalResourcesLimited TechnicalSupport


MatureFineTailingsDrying(MFTD)ResearchCOSIAProjectNumber:TJ0028



Status:Ongoing

PROJECTSUMMARY

The purpose of this project is to evaluate and develop techniques to understand flocculation fundamentals ofmature fine tailings (MFT)usingamulti-phaseapproach. MFT isasubsetof fluid fine tailingswithsand-to-finesratiooflessthan1andsolidscontentgreaterthan30%,nominal.MFTisverydifficulttodewaterandsoadvancesin dewatering ofMFTwill accelerate tailings pond reclamation and closure. The twomost recent goals of theproject are the application of focused beam reflectance measurement to MFT floc size measurement and thedevelopmentofapopulationbalancemodelforslurryflocculation.

FocusedBeamReflectanceMeasurementApplicationinMFTFlocSizeMeasurement:

Opticalmeasurementtechniquesarebecomingmorewidespread invarious industrialapplications. Inparticular,focusedbeamreflectancemeasurement(FBRM)isutilizedasamonitoringtoolforparticlesizedistribution(PSD)inslurries.Atthesametime,limitedinformationisavailableonhowflowparameters,suchasvelocityandparticlesvolumefraction,mayaffectFBRMmeasurements.Inthiswork,weattemptedtoclosethisgapbyexaminingwatersuspensionsofwell-characterizedparticles(glassbeadsandplastic)ofdifferentdiameter,opacityandshapeundervarietyofconditions.

PopulationBalanceModelDevelopmentforSlurryFlocculation:

Suspensionsofveryfineparticlestendtoexhibitresistancetosettlingduetotheirsizeandelectricalcharge.Oneofthemethodstofacilitatesettlinganditsaccompanyingwaterreleaseistheadditionofapolymertotheslurry.Thepolymerbindsfineparticlesoftheslurryintolargerflocsthatthenbecomemoreamenabletoseparation.Thisprocessiscalledflocculationandiscommonlyusedinthetreatmentofoilsandstailings.Duetoitsimportanceinenvironmentalandoperationsperformanceandcostreduction,mucheffortisdirectedtobetteringunderstandtheflocculationphenomenon.Numericalmodellingispartofthiseffortasitrevealstheinternalstructureoftheflow,alongwithcomplexmulti-phaseinteractions.


ItwasobservedthatthedistributionoftheglassbeadsappearssignificantlywiderthanthecorrespondingPSD.Itislikelyduetotheloweropacityofglassbeads.Atthesametime,theshape,whichissphericalfortheglassbeadsandrandomfortheplasticparticles,doesnotappeartoplayarole.Itwasshownthattheinfluenceofthematerialvelocity on the measurement results is relatively small for most of the range of parameters considered. The


influence of the volume fraction appears to be very significant. For most of the considered particleconcentrations,theincreaseofthevolumefractionofparticlesleadstothedecreaseofthemeasuredFBRMsize.

The developed Population Balance Model considers floc formation, fractal growth and breakage, influence ofpolymer concentration, rheological changes associatedwithpolymermixing and flocculationprogress, and flowregimechanges.Eulerianmulti-fluidrepresentationisadoptedforliquidandflocphaseswiththepoly-dispersedfloc size distribution being represented through the population balance approach. Themodel was tested andadjustedbasedonavailableexperimentaldatafordifferentflocculationconditions.

LESSONSLEARNED

• Formostoftheconsideredparticleconcentrations,theincreaseofthevolumefractionofparticlesleadstothedecreaseofthemeasuredFBRMsize.

• Eulerianmulti-fluidrepresentationisanimportanttoolforMFTflocculationmodelling.


Hosseini,M.,Pougatch,K.,Delfel,S.,Moyls,B.,Revington,A.,Sadighian,A.2018.FBRMApplication toEvaluateParticleSizeinSuspensions,presentedatXXIXInteramericanCongressofChemicalEngineeringIncorporatingthe68thCanadianChemicalEngineeringConference,October28-31,Toronto,ON.

Hosseini, M., Pougatch, K., Delfel, S., Moyls, B., Revington, A., Sadighian, A. 2018. Population Balance ModelDevelopment for Slurry Flocculation, presented at XXIX Interamerican Congress of Chemical EngineeringIncorporatingthe68thCanadianChemicalEngineeringConference,October28-31,Toronto,ON.



PrincipalInvestigator:AdrianRevington


orJobTitle

DegreeStartDate

(ForStudentsOnly)


(ForStudentsOnly)

AdrianRevington SuncorEnergyInc. TeamLead ArdalanSadighian SuncorEnergyInc. ProjectLead

BennyMoylsCoandaResearch&DevelopmentCorporation ProcessEngineer


ResearchCollaborators:CoandaResearch&DevelopmentCorporation


DeepCohesiveDepositModellingCOSIAProjectNumber:TJ0045



Status:Ongoing

PROJECTSUMMARY

Deep deposits of cohesive treated fluid fine tailings (FFT) have the advantages of minimizing the footprintrequirement for tailings management and avoiding the multiple material re-handling requirements of thin-liftdeposit operations. The long-term dewatering and densification of these deep deposits are expected to beprimarilydrivenby large-strain consolidation. However, in the interveningperiodsduringandafterdeposition,otherdewateringmechanisms(suchassedimentation,atmosphericdryingandunder-drainage)maybeimportant.Itisimportanttoaccuratelypredictthelong-termperformanceofthesedeepdepositssothatoptimumdecisionsrelatedtodeposition,depositmanagement,capping,reclamationandclosureoperationscanbemade.Onecost-effective way of predicting this long-term performance is through numerical modelling. However, availablenumericalmodels are limited in that they are unable to couplemost or all of the aforementioned dewateringmechanismstolarge-strainconsolidation.Thepurposeofthisprojectwastodevelopanumericalmodelthatcanintegrateallthesedewateringmechanismsinasingleplatform.Thenumericalmodelwassuccessfullydevelopedand benchmarked against other numerical models and publicly available data for oil sands and non-oil sandstailingsmaterials.Thenumericalmodelwasalsosuccessfullycalibratedagainstafielddepositof10mdeepin-lineflocculatedFFTattheSyncrudeCanadaLtd.site.


Thenumericalmodelwasdeveloped,withthecapabilityforcouplinglarge-strainconsolidationtosedimentation,atmospheric drying (evaporation and freeze-thaw dewatering) and under-drainage. The numerical model wassuccessfully benchmarked against other numerical codes for cases involving coupling sedimentation toconsolidation, foravarietyofmaterialssuchassand,naturalsediments,clayslurriesandoilsandstailings. Thebenchmarkingexercisecoveredavarietyofdeposition(instantaneousandstagedfilling),capping(capandnocap)and initial condition (homogenous and heterogeneous initial profile) scenarios. In particular, the long-termbehaviourof theUniversityofAlberta standpipe#1was reasonablypredictedwith thenumericalmodelwhensedimentation was implemented in addition to large-strain consolidation. Also, the numerical model wassuccessfullycalibratedtoSyncrudeCanadaLtd.’s10mdeepaccelerateddewatering(ADW)deposit.Implementinglarge-strainconsolidationaloneinthenumericalmodelgrosslyunder-predictedthefieldperformanceoftheADWdeposit.However,whenallthemechanismsobservedinthefield(sedimentation,atmosphericdryingandunder-drainage)wereincludedwithconsolidationinthemodel,thepredictionsagreedwithfieldperformancedata.


LESSONSLEARNED

Alarge-strainconsolidationmodelwasdevelopedthatwasabletocouplealltherelevantdewateringmechanismsfordeepcohesivedeposits.Suchacoupledlarge-strainconsolidationmodelisrequiredtoaccuratelypredictthelong-termperformanceofdeepcohesivedepositswhereotherdewateringmechanisms,inadditiontoself-weightconsolidation,arerelevant.Fortailingsdepositswithinitiallylowsolidscontent,implementingsedimentation,inadditionto large-strainconsolidation, is important toaccuratelypredict the long-termbehaviourof thedeposit.This was illustrated in the case of the ADW deposit where field deposit performancewas substantially under-predictedbythemodel,evenwhenall theothermechanismswerecoupledto large-strainconsolidation,unlesssedimentationwasincluded.



PrincipalInvestigator:AdedejiDunmola


orJobTitle

DegreeStartDate

(ForStudentsOnly)

ExpectedDegreeCompletionDate

orYearCompleted

(ForStudentsOnly)

JimLorentz SyncrudeCanadaLtd. TeamLeader AdedejiDunmola SyncrudeCanadaLtd. GeotechnicalAssociate NanWang SyncrudeCanadaLtd. SeniorAssociate-Chemical MurrayFredlund SoilVisionSystemsLtd. President/CEO


EvaluationofVerticalStripDrainsinOilSandsTailingsCOSIAProjectNumber:TJ0049

ResearchProvider:SNCLavalinInc.CentreforAdvancedTestingandResearch,formerlyMDHEngineeredSolutionsCorp.



Status:Year5of5

PROJECTSUMMARY

In 2010, Suncor Energy Inc. began construction of a floating cover over the soft tailings of Pond 5. This wasintended toprovidea trafficable surfaceonwhich reclamationactivities couldultimately lead to the closureofPond5.Akeycomponentofthisapproachwasthatthesurfaceoftailingsbestrengthenedsufficientlytosupportreclamationactivities. Anetworkofverticalstripdrains(VSD)was installedtospeedconsolidationbyprovidingseepagepathsforwatertodrainfromthetailings.

An experimental setupwas devised of a 0.5m diameter column filledwith 3m height of mature fine tailings(MFT),whichwasfullyinstrumentedandallowedtoconsolidatewithawickdraindownthecentreofthecolumn.Theprojectwasseparatedintodifferentphasesofwork:

1. Phase1(2011–2012) involvedameasuringtheconsolidationunderself-weightconditions(noexternalload) to evaluate the effectiveness of VSD in dewateringMFT. This columnwas also dismantledwithsamplestakenfortestingaftereightmonthsofconsolidation.

2. Phase2A(2013–2014)followedinwhichtheMFTfromPhase1washomogenisedandplacedintothesamewickdrainedvesselundera40kPasurchargeload(representingapproximately2mofsoilcover).Thissurchargingcontinuedfor11months,afterwhichthesettlementsloweddownsothesurchargewasincreasedto60kPa.

3. InPhase2B(2014–2016),a60kPasurchargewasappliedtothecolumnandtheeffectonspeedingupthe rate andmagnitudeof consolidationwasmeasured. The columnwas dismantled and tested afterapproximately twoandahalfyearsofconsolidation. This involvedsamplingand testing innine layers,workingdownwardfromthetopbycuttingandremovinglayersofthetestcolumn,toprovideaccessfortestinglowerlevels.Thetestingofeachofthelayersinvolvedmeasuringwater/solidscontent,strength,bitumencontent,claycontent,andspecificgravity.

This laboratoryprogramwas intended toprovidebaselinedataonwhich future studieson theeffectivenessofaddingsurchargeload,changingVSDdepths,andspacingcouldbeevaluated.



Allphasesoftheprojectwerecompletedby2017,withthefinalreportcompletedin2018.Theresultsofthetestprogram found that the loading systemwas capable of simulating the effects of surcharge loading on theMFTinsidethetestcolumn.ItdemonstratedtheeffectivenessoftheVSDandsurchargeloadinginincreasingtherateofsettlementandthebuild-upofeffectivestress. Italsofoundthathigherlevelsofsurchargewererequiredtolower the water content below the liquid limit (i.e., increase the solids content above 70%). See the lessonslearnedsectionforfurtherinformation.

LESSONSLEARNED

Throughoutthefiveyearsoftesting,theVSDEvaluationinOilSandsTailingsprojectyieldedthefollowinglessonslearned:

• Increased loadingwas found to significantly increase the rateof settlement in the test columnwithoutmeasuringabitumenmigration,whichmayblindoffthewick.

• Largestrainconsolidation(LSC)derivedcompressibilityvalueswereconsistentwiththemoisturecontentsandeffectivestressesmeasuredinthecolumn.

• Consolidation analysis using the LSC derived parameters was able tomatch themeasured self-weightconsolidationperformanceofthewick-drainedcolumn.

• StrengthsmeasuredinthecasingwereconsistentwiththosemeasuredaspartofanotherSuncorEnergyInc.study,SlurrytoSoil.

• A surcharge greater than60 kPawill be required to get thisMFT to amoisture content lower than itscorrespondingliquidlimit.

The settlementdata,porepressuresandmeasured solids contentprofileshavealsobeenpreserved for furtherfutureanalysisinotherconsolidationsimulations.



Haug,MoirD.andGan,Julian2018.TestcolumnstudyinVSDaidedself-weightconsolidationofoilsandstailings.GeoEdmonton2018,Paper330.

Haug,MoirD.,Gan,JulianandAl-Mamun,Mohammad2018.ImpactofsurchargeloadingonVSDperformanceindewateringoilsandstailings.GeoEdmonton2018,Paper347.

Haug,MoirD.,Gan,Julian,Kaminsky,HeatherandAl-Mamun,Mohammad2016.Permeabilityofoilsandstailings–acomparisonofdirectconstantheadmeasurementswithbackcalculatedhydraulicconductivitymeasurementsfromlargestrainconsolidationtest.InternationalOilSandsTailingsConference2016,LakeLouise,AB,Canada.pp.340-347



Institution:SNCLavalinInc.CentreforAdvancedMaterialsTestingandResearch,Saskatoon,SK

PrincipalInvestigator:MoirD.Haug


orJobTitle

DegreeStartDate

(ForStudentsOnly)


(ForStudentsOnly)

MoirD.HaugSNCLavalinInc.CentreforAdvancedMaterialsTestingandResearch

PrincipalInvestigator

JulianGanSNCLavalinInc.CentreforAdvancedMaterialsTestingandResearch

SeniorResearcher


DeepDepositModelling,AtmosphericFinesDryingTestCellsCOSIAProjectNumber:TJ0058

ResearchProvider:CanadianNaturalResourcesLimited(CanadianNatural)


Status:Completed

PROJECTSUMMARY

Theobjectiveofthisprojectistodevelopreclamationtechnologyforoilsandsmines.Themaingoalforoilsandsmining reclamation is to build reclaimed landforms that are capable of supporting a self-sustaining, locallycommonborealforest.Thereareanumberofkeyrequirementsrelatedtolandformdesign,including:strengthofthesurfaceoftailingsdepositstoallowcapplacementandcontouring,long-termsettlementofthetailingsanditsimpactonuplandareas,reclaimedwetlands,andthequantityandqualityofwater.

TheprojectwasafieldstudyusingCanadianNatural’satmosphericdrying(AFD)processforfluidfinetailings(FFT)management at itsMuskeg RiverMine. The AFD process consists of thin-life dewatering of in-line flocculatedmature fine tailings (MFT). The study’s goal was to assess the short-term (one- to two-year) dewatering andresultantstrengthgainperformanceofthin-liftlayeringversusdeepstackingdepositionalapproaches.Thestudysystematicallyevaluatedwhetherusingmultiple lifts, includingboththinandthick lifts,orasingledeepdepositwasabettertailingsmanagementstrategytopursueusingtheAFDprocess.Theobjectiveswereto:

• Comparetheamountoffinesprocessedperunitareatopeakshearstrengthof5kPainoneyear;• Quantifyandassesstherelativecontributionofevaporativedryingandconsolidationtowardsdeposit

dewatering;and• Comparethepotentialforfreeze-thawdewatering.

Threetailingsdepositionalapproaches—thinlifts(ThinML),thicklifts(ThickML),anddeepstacking(DeepStack)—wereinvestigated.

FortheThinMLdeposit,seventhinliftsoftreatedMFTweredepositedoverthecourseofoneyear(August2012toAugust2013),onanapproximate30-daycycle.Eachliftaveragedapproximately0.6minthickness.

Threethick liftsoftreatedMFTweredepositedoverthesametimeperiodonanapproximate90-daycycle,andaveraged1.4minthicknessfortheThickMLdeposit.

TheDeepStackingconsistedofone4.5-metre-thickliftoftreatedMFTplacedinacontinuouspouronOctober4,2012.



All three deposits had similar amounts of dewatering, increasing from an initial average solids content ofapproximately38%toafinalaveragesolidscontentof62%aftertwoyears. However,theirratesofdewateringdiffered, and themagnitudeofdewateringattributed to flocculation, sedimentation, consolidationphenomena,and evaporative drying differed between deposits. The results of the test program suggest that producingmaterialmeetingdesignspecificationsanddeepstacking—toexploittheenhanceddrainageattributedtoalargerdriving head and initially higher permeable material—is a superior approach to multiple layering for depositsfocusedonshort-term(oneyearorless)dewateringandstrengthgainperformance.

Noneof thedepositionalapproachesachievedmaterialwithhighenoughsolidscontentor strengthmeaningfulenough to achieve stable, soil-likematerial for incorporation into a terrestrial reclamation landscape after twoyears.Enhanceddewateringmethodsconsistingofsurcharging/capping,sandlayering,wickdrains,rimditching,orotherswerethenconsideredtoadvancethesematerialstowardreclamationreadiness.

In2016and2017aseriesoftrafficability,cappinganddrainagestudieswereconductedonthedeepstacktestcell.The2018activities includedacomprehensivesamplingandanalysiscampaigntodeterminetheresponseof thecell subsequent to capping and the placement of wick drains. The cell was mined through shortly after thesamplingwascompletedandthisprojectwillbecompletedwithafinalreportinearly2019.

LESSONSLEARNED

Thethreedepositconfigurationsendedwithasimilaraveragesolidscontentof62%,buttheprofilesaredifferentas the result of variable dewatering. TheDeep Stack has a characteristic ‘C’ shape as the result of self-weightconsolidation andevaporation impact in theupperonemetreof thedeposit. By comparison, theMLdepositshavebothhigher solids content crusts anddensified layers and lower solids content regions that resulted fromincompleteconsolidationordryingpriortosubsequentliftplacement.

Solids contents in the crust approached 75% with peak shear strengths over 20 kPa prior to subsequent liftplacement.TheburiedcrustsintheMLcellsrewettedbutretainedrelativelyhighersolidscontentintervalswithinthe deposit profile as stacking continued. The buried crusts in the ML cells, though relatively thin, had lowpermeability zones that impeded drainage and relief of excess pore water pressure generated by progressivelayering. Over time, theburiedcrustsbecame lessdistinguishable,and thedepositbegan tobehaveasamoreuniformdeposit.



Kolstad, D., Dunmola, A., Dhadli, N., O’Kane, M., Song, J., and Masala, S. 2012. Towards the Improvement inGeotechnicalPerformanceofAtmosphericFinesDrying(AFD)atShell’sMuskegRiverMine.IOSTC2012:PresentedattheThirdInternationalOilSandsTailingsConference,Edmonton,Canada,December2-5,2012.


Dunmola, A., Cote, C.,Freeman, G., Kolstad, D., Song, J. and Masala, S. 2013. Dewatering and Shear StrengthPerformanceof In-lineFlocculatedMatureFineTailingsUnderDifferentFieldDepositionalSchemes.PresentedatTailingsandMineWaste’13,Banff,Canada,November3-6,2013.

Adedeji Dunmola, A. and Nag, 2013. Shell’s Atmospheric Fines Drying Technology for Dewatering Mature FineTailings–Past,PresentandFuture.PresentedatTailingsandMineWaste’13,Banff,Canada,November3-6,2013.

Masala,S.,Nik,R.M.,Freeman,G.andR.Mahood,R.2014.GeotechnicalInsightsintoDeposition,DewateringandStrengthPerformanceofThickenedandPasteTailingsDepositsatShellCanadaTailingsTestFacility.IOSTC2014.PresentedattheFourthInternationalOilSandsTailingsConference,LakeLouise,Canada,December7-10,2014.

Kolstad,D., Borree, B., Song, J. andMahood, R. 2016.Field Pilot PerformanceResults for Flocculated Fluid FineTailingsUnderThreeDepositionalVariations. IOSTC2016.Presentedat theFifth InternationalOil SandsTailingsConference,LakeLouise,Canada,December4-7,2016.



PrincipalInvestigator:GavinFreeman


orJobTitle

DegreeStartDate

(ForStudentsOnly)


(ForStudentsOnly)

AdedejiDunmola SyncrudeCanadaLtd. RezaMoussaviNik Imperial CynthiaCote CanadianNaturalResourcesLimited RobertMahood Imperial


ConsolidationofFluidFineTailingsCOSIAProjectNumber:TJ0059



IndustryCollaborators:SuncorEnergyInc.

Status:Year5of10

PROJECTSUMMARY

Theobjectivesof the fluid finetailings (FFT)consolidationprojectare tounderstandthe long-termconsolidationbehaviourofFFTandtoevaluatetheperformanceofvariousflocculantsandprocesstreatmentsforFFT.

TheprojectbeganwithaseriesoflaboratorytrialsusinggeocolumnstocomparedifferenttypesofFFTtreatments.Geocolumnsare largeinstrumentedclearcylinders(3mhigh)thatareusedinthelaboratorytomeasuretailingsconsolidation(densitydifferentials)andtovisuallyobservechanges intailingsconsolidation. TheFFTtreatmentsincluded different flocculants, varying dosage rates of flocculants, and centrifugation. It was hypothesized thatcomparing a large number of different treatments in the laboratorywould be indicative of themost promisingtailingstreatmentsforfurthertesting.Bothvisualanddensityobservationsweremadeovertime,withthelessonslearned from the laboratory trials applied to the development of the subsequent tailings consolidation casingexperiment.

Followingthelaboratorytrials,theTailingsConsolidationCasingExperimentalProjectPilot(TCCEPP)wasinitiated.TheTCCEPPisafieldscalepilotdesignedtoconductconsolidationexperimentsusingeightinstrumentedcolumnsorcasings(3mwidex10mdeep)filledwithvariousFFTtreatments.Thecasingsareatascalethatapproachestheexpectedgeotechnical stresses anticipated in field scale tailingsdeposits andare consideredanalogues todeep,fines-dominatedtailingsdeposits. Sevencasingswerefilledat theAlbianSandsSharkbitemine in2015withthefinal casing filled in 2016. The treatments consist of various combinations of centrifuged and flocculated FFT.Casing 1 and Casing 7 were filled with Muskeg River mine (MRM) and Jack Pine mine (JPM) untreated FFT,respectively.Theyserveastheexperimentalcontrolsforparameterssuchassettlingrates,densificationandshearstress. Casings 2 to 4were filledwithMRMFFT treatedwith various dosages of flocculants added in an in-lineprocess.Casings5and6werefilledwithFFTfromSuncorEnergyInc.treatedwithdifferentflocculantsatvariousdosages. Casing 8 was filled with JPM centrifuged flocculated tailings. Once the casings were filled,instrumentationwasinstalled,andFFTsampleswerecollectedtodeterminepercent(%)solidscontent,%water,yieldstrength,voidratioanddensitychanges.Monitoringandsamplingwereconductedovertimeanddepth.

Thegeotechnicalinformationfromtheseprojectswillassistinplanningandschedulingtailingsdepositiontomeetclosurelandformobjectivesfordeepfines-dominatedtailingsdeposits.



Knowledgefromthisprojectwill:

• enhancetheindustry’sunderstandingofcohesivedepositconsolidationinoilsands;• provideconfidenceinmeetingclosureandreclamationplansandfinallandformobjectives;• provide industry with the basis for decision-making regarding centrifuged FFT placement, capping and

drainagemanagementoptionstocreatetargetedlandforms;and• offer insight into fines-dominated deposit performance variables that, in turn, may initiate new

fundamentalgeotechnicalresearchwork.

Ineachyearsincefilling,monitoringofthedepositperformancecontinuedandsamplesweretakentodetermine% solids content, % water, yield strength, void ratio and density changes over time and depth. Results areinfluencing subsequent evaluation as well as optimizing current FFT treatment technologies. Modelling is inprogresstoevaluateconsolidationpropertiesforeachcasingandtodeterminethepotentialforscale-up.

LESSONSLEARNED

Thisprojectseekstoadvancetheoilsandsindustry’sunderstandingofcohesivedepositconsolidationinoilsands.Theeffectofdifferenttreatmentsonconsolidationbehaviourisstudied.

Preliminary results show that tailings treated with flocculant settle quicker and contain higher shear stresscapabilities than untreated or centrifuged tailings. Identification of a MFT chemical amendment resulting inimproved consolidation performance was achieved. This performance included higher deposit permeability atlowervoidratios;i.e.,athigherpercentsolidscontentandfurtherconsolidation.Ultimately,thisinformationwillbeusedtofurtherdeveloptailingstechnologyforfull-scaleimplementation.



Stianson,J.,Mahood,R.,Thomas,D.,Li,L.,andSong,J.2016.AShellTailingsConsolidationCasingExperimentalPilotProject(TCCEPP).IOSTC2016:PresentedattheFifthInternationalOilSandsTailingsConference,LakeLouise,Canada,December4-7,2016.

Stianson, J., Mahood, R., Fredlund, D., and Sun, J. 2016. Large-strain Consolidation Modelling to DetermineRepresentativeTailingsConsolidationPropertiesfromTwoMeso-scaleColumnTests.IOSTC2016:PresentedattheFifthInternationalOilSandsTailingsConference,LakeLouise,Canada,December4-7,2016.




PrincipalInvestigator:GavinFreeman


orJobTitle

DegreeStartDate

(ForStudentsOnly)


(ForStudentsOnly)

AdedejiDunmola SyncrudeCanadaLtd. RezaMoussaviNik Imperial RobertMahood Imperial CynthiaCote Imperial


SeepageInducedFlocculationTestingofMatureFineTailingsCOSIAProjectNumber:TJ0068

ResearchProvider:UniversityofBritishColumbia,UniversityofColoradoBoulder,CoandaResearch&DevelopmentCorporation


Status:Year2of2

PROJECTSUMMARY

Effectivestewardshipofmaturefinetailings(MFT)isimportantforoilsandsmining,reclamationandclosure.MFTtreatedwith flocculants has been shown to settle quicker than untreated tailings, improving consolidation andreleaseofwater. AspectsoftheflocculationorMFTtreatmentprocesssuchasthequalityoftheresultingflocs(i.e., the clumps of fine particles formed during flocculation) and the associated release ofwater influence therapidityof dewatering and consolidationbehaviour. Upuntil 2015 thequestionof how the importanceof flocstructuretolong-termdewateringoftreatedMFT(tMFT)hadnotbeeninvestigated;however,withadvancementsinMFTflocculationprecision(i.e.,dosageandmixingconditions) implicationstolong-termbehaviourfora leavein-placestackeddepositordeepdepositcannowbeexamined.Thepurposeofthisprojectwastodeterminetheimpactofflocculationefficiencyonlong-termconsolidationbyusingseepageinducedconsolidationtesting(SICT).

In 2015, Suncor Energy Inc. partnered with the University of British Columbia and the University of ColoradoBouldertoconductSICTondifferenttMFTtreatmentsto investigatetheeffectsofflocculationonconsolidation.SICT is a relatively rapid method to determine the consolidation parameters of a soil subject to large strains.Consolidation parameters of interest are the hydraulic conductivity and compressibility relationships, wherecompressibilitydeterminesthevolumechangeofthesoilwhenagivenloadisapplied,andhydraulicconductivitydetermines theduration for thevolumechange tooccur. SICThasbeenused inotherconsolidation testingonuntreatedMFTwithsomesuccess,andisquickeratonetotwomonthsversustheyearrequiredforLargeStrainConsolidation(LSC)testing.

AnexperimentalsetupwasdevisedwhichincludedaSICTtesttodeterminetheconsolidationparametersforfivedifferent flocculent treatments and one untreated MFT. A single trained individual obtained samples of thetreatedanduntreatedMFTthroughmultiplehandflocculationsina10cmcup.InadditiontothetMFTintheSICTcell, six60cmcolumnswereconstructed foreachof thedifferent treatments. Thecolumnsweredestructivelysampled after one, three, eight, 14, 30 and 60 days to provide validation data for the consolidationmodellingpredictions.

TheSICTpredictionswerethencomparedwiththemeasuredvaluestoshowagreementandwhereconsolidationtheoryapplied,aswellaswhereitdidnot.



Theprojectwascompletedin2016.Afinalreportandconferencepresentationwereprepared.Insummary,theSICTapproachwasvalid for the rapiddewatered tMFTtestedandclear improvementof theoptimaldosedandoptimallymixedtMFTswasevident.

FurtherdetailsarediscussedintheLessonsLearnedsection.

LESSONSLEARNED

Throughoutthetesting,thefollowingwaslearnedaboutSICTofMFTandtMFT:

• SeepageinducedconsolidationtestingisanappropriatemethodologyfordeterminingconsolidationcharacteristicsforbothtreatedanduntreatedMFT.ThehydraulicconductivityoftheflocculatedMFTincreasesbyuptooneorderofmagnitudewhencomparedtotheuntreatedMFT.

• TheflocculationprocesshaslesseffectonthecompressibilitycharacteristicsofthetreatedMFT.Italsodoesnotnegativelyaffectthefinalstoragevolume.Theremay,however,beasignificantimpactofthedifferenceduringtheinitialfill.

• TreatedMFTexhibitrandomcompressibilitybehaviouratloweffectivestresses.Consolidationmodellinginthiszoneisnotappropriate,astheslurrydoesnothavesoil-likecharacteristics.Determiningtheeffectivestressorvoidratioatwhichthematerialtransitionsfromanopenandrandomstructuretoamoreslurry-likehomogeneousmixtureisacriticalstepinanymodellingeffort.

• Forthetestedmaterialandtreatmentmethodsthattransitionistakingplaceatabout1kPaeffectivestressoravoidratioofabout2.5,dependingonthetreatmentprocess.



Znidarcic,D.,VanZyl,D.,Ramirez,M.,Mittal,K.,Kaminsky,H.2016.ConsolidationCharacteristicsofFlocculatedMFT–ExperimentalColumnandSICTData. Fifth InternationalOilSandsTailingsConference2016,LakeLouise,AB,Canada.pp.408-515



Institution:NormanB.KeevilInstituteofMiningEngineering,UniversityofBritishColumbia,VancouverB.C.;UniversityofColoradoatBoulder,DepartmentofCivilEngineering;CoandaResearch&DevelopmentCorporation

PrincipalInvestigator:DirkVanZyl


orJobTitle

DegreeStartDate

(ForStudentsOnly)


(ForStudentsOnly)

DirkVanZylDepartmentofMiningEngineering,UniversityofBritishColumbia

PrincipalInvestigator

DobroslavZnidarcicDepartmentofCivilEngineering,UniversityofColorado,Boulder,CO

Co-PrincipalInvestigator

KushagraMittal CoandaResearch&DevelopmentCorporation SeniorResearcher


DeepDepositFilling,MonitoringandModellingCOSIAProjectNumber:TJ0072

ResearchProvider:GolderAssociatesLtd.


Status:Year4of8

PROJECTSUMMARY

Theobjectiveof this project is todevelop adatabaseof consolidationparameters for a commercial scaledeepthickenedtailingsdeposit.Theconsolidationparameterswillbeusedtomodellong-termconsolidationbehaviourof the deposit. The actual performance of the deep commercial scale depositwill bemonitored annually andcomparedwiththepredictedperformanceofthemodeltovalidate(andcalibrate)consolidationparameters.

Currently,theoilsandsindustrylacksasuiteofconsolidationparametersthatarecalibratedagainstacommercialscaledeposit.Mostexistingconsolidationmodelsarebasedonsand-to-finesratio(SFR).Thisprojectaimstoclosethatgapbyprovidingasetofconsolidationmodellingparameters—includingclaycontent—applicabletonewandexisting deep deposits. It is anticipated that themodelwill validate or require changes to current operationalpracticessothatlong-termclosureofthedeepdepositcanbeachieved.

Thickenedtailings(TT)areusuallyproducedbycombiningfreshtailingswithagedfluidfinetailingsremovedfroma tailingspond. If the thickenerunderflow ishydraulically transported to thedepositionalarea, shearingof thethickenedmaterialoccurs. This isunavoidable. Re-flocculationofshearedmaterialat theendof thepipe isanoption to rebuild the shearedmaterial floc structure, enhance dewatering of thickened tailings and acceleratewaterreleaseatthedepositionarea.

Hydraulic placement of TT tends to create different zones within the tailings deposit based on the hydraulicmigration capabilities of the TT layers. These naturally created zones consolidate differently due to thecomposition(claycontent,finescontent,initialvoidratio,etc.)ofeachzone.Inaddition,thickenerfeedvariabilityalso results in deposits with varying composition and consolidation properties. Thus, a suite of consolidationparameters rather than one set of parameters or averages are required to model the entire deposit and itsdifferentTTzones.

In phase one of the project, laboratory scale testing was carried out to simulate and produce samples withpotentiallydifferentcomposition. Differentratiosof freshtailingsandfluid finetailingsweremixedtosimulatethe thickening process as well as the secondary re-flocculation treatment process. Materials with differentcompositionandvaryingthefeedrangeweretestedinlargestrainconsolidation(LSC)cells(oroedometercells)tomeasurecompressibilityandhydraulicconductivityofthetailingsmixtures.

Inphasetwoofthestudy,insitusampleswerecollectedfromthecommercialscaletailingsdepositandtestedtodetermine the same properties as in phase one, such as compressibility and hydraulic conductivity. These


propertieswillbeusedtomodelconsolidationbehaviourofthecommercialscaledeposit.Depositbehaviourwillbe determined though annual in situ sampling and testing and will be compared to the modelled predictiveconsolidation behaviour. The predictive consolidation model will be calibrated accordingly with the annualsamplingandtestingresults.


Large strain consolidation (LSC) tests were conducted to determine compressibility and hydraulic conductivityparametersforsampleswithdifferentcomposition.Samplesfabricatedinthelabandinsitusampleswereusedtomeasure those parameters. The following two figures illustrate some of the measured parameters (effectivestress,voidratio,hydraulicconductivity)atvariousSFR,claycontent, location(beachabovewater[BAW],beachbelowwater[BBW],orLSC.


LESSONSLEARNED

Itisrecognizedthatsubsamplingerrorsandotherlaboratoryerrorsareunavoidableinmeasuringindexpropertiessuch as hydraulic conductivity. Therefore “engineering judgment” should be used in selecting ranges forconsolidationproperties.

LITERATURECITED

Canada’sOilSandsInnovationAlliance(COSIA)2016.Unifiedfinesmethodforminus44micronmaterialandforparticlesizedistribution.CompiledbyCOSIAfinesmeasurementworkinggroup,February2016.

Canada’sOilSandInnovationAlliance(COSIA).2015.GuidelineforTailingsDepositSamplingandMeasuringTools.PreparedbyCOSIAGeostatisticalandDepositSamplingWorkingGroup.April27,2015.



Weerakone,W.M.S.B.,Ren,W.2018.Acceleratedoilsandtailingsdewateringwiththickeningandreflocculation,PresentedatIOSTC2018.InternationalOilsandTailingsConference,Edmonton,Canada,December2018.


Institution:Imperial

PrincipalInvestigator:SidanthaWeerakone


DegreeorJobTitle

DegreeStartDate

(ForStudentsOnly)


(ForStudentsOnly)

SidanthaWeerakone ImperialTailings/GeotechnicalEngineer

WeiRen ImperialSeniorAdvisor,MineralProcessing

PaulCavanagh Imperial SeniorTechnicalAdvisor

JasonStianson GolderAssociatesLtd.Associate–GeotechnicalEngineer


AcronymsandGlossary

ADW accelerateddewatering

AER AlbertaEnergyRegulator

AFD atmosphericfinesdrying

behaviouroffluidfinetailings

measuredresponseofthefluidfinetailingsinatailingsdepositovertime

BAW beachabovewater

BBW beachbelowwater

CFT centrifugefinetailings

coagulation Theagglomerationoffineparticlesinatailingsslurry,usuallybytheadditionofa chemical agent that alters the electrical charge on those particles, therebyreducinginter-particlerepulsiveforces

COSIA Canada’sOilSandsInnovationAlliance

CST capillarysuctiontime

Directive074 Directive 074: Tailings Performance Criteria and Requirements for Oil SandsMiningSchemes

Directive085 Directive085:FluidTailingsManagementforOilSandsMiningProjects

EPA EnvironmentalPriorityArea

FFT fluid fine tailings – a liquid suspension of oil sands fine tailings or fines-dominatedtailingsinwater,withasolidscontentgreaterthan2%butlessthanthesolidscontentcorrespondingtotheLiquidLimit.

fines mineral solidswithparticle size equal toor less than44μm (doesnot includebitumen)

flocculation The“clustering”offineparticlesinatailingsslurryintogroupsor“flocs,”usuallybytheadditionofachemicalagentthatbindstothoseparticles, therebytyingthemtogether

FLT flotationtailings

geotechnicalfinescontent massoffinesdividedbymassofsolidsx100%

geotechnicalwatercontent massofwaterdividedbymassofsolidsx100%

LiquidLimit The geotechnicalwater contentdefining theboundarybetweena liquid andasolid in soil mechanics. This state is defined by a standard laboratory testmodifiedforuseinoilsandstailingscontainingbitumen.ItcanalsobedescribedintermsofanequivalentFOFW(finesoverfines+waterratio)orsolidscontent.Thistestresultsinanequivalentremouldedshearstrengthof1to2kPa.

MFT maturefinetailings–fluidfinetailingswithalowsand-to-finesratio(<0.3)andasolidscontentgreaterthan30%(nominal)

PSD particlesizedistribution

SC solidscontent–massofsolidsdividedbymassof (solids+bitumen+water)x100%


SFR sand-to-fines ratio – themass ratio of sand-to-fines; i.e., themass ofmineralsolids with particle size >44 μm divided by the mass of mineral solids withparticles≤44μm

solids sand, clay and other solid particles contained in oil sands tailings (does notincludebitumen)

TEA terminalelectronacceptors

TFT thinfinetailings–asubsetoffluidfinetailingswithasand-to-finesratiooflessthan1andasolidscontentlessthan30%(nominal)

TROTM TailingsReductionOperation

TT thickenedtailings

voidratio volumeofvoidsdividedbyvolumeofsolids

watercontent massofwaterdividedbymassof(solids+bitumen+water)x100%

μm micronsormicrometres(onemillionthof1m)

Documents

2018 Tailings Research Projects Annual Report FINAL 03Jun2019 › sites › default › files › attachments... · Create a cap-isolating layer with a water cap in place Sand capping