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SPE DISTINGUISHED LECTURER SERIESis funded principally
through a grant of the
SPE FOUNDATIONThe Society gratefully acknowledges
those companies that support the programby allowing their professionals
to participate as Lecturers.
And special thanks to The American Institute of Mining, Metallurgical,and Petroleum Engineers (AIME) for their contribution to the program.
The Latest in Ways to Improve Asset Value Through
Better Water Management
Steve CheungSteve CheungChevron Energy Technology Company Chevron Energy Technology Company
California, USACalifornia, USA
OverviewIntroductionIntroductionPreventionPreventionDiagnosis Diagnosis –– Interwell tracerInterwell tracer
Solutions (mechanical, chemical, others)Solutions (mechanical, chemical, others)–– InIn--depth for reservoir problemdepth for reservoir problem–– Near wellbore for producer problemsNear wellbore for producer problems
IntegrationIntegration
Produced Water Management
The world produces 300The world produces 300-- 400 million barrel 400 million barrel of water per day for 75 million barrel of oil of water per day for 75 million barrel of oil
SPE77963(2002)SPE77963(2002)
New fields: New fields: –– preventionprevention–– reduce Creduce CAPEX / OPEX for the life of field.APEX / OPEX for the life of field.
Mature fields: Mature fields: –– many are more than 90% water cut many are more than 90% water cut –– delay abandonment to maximize recovery.delay abandonment to maximize recovery.
Waterflood Management OperationsWaterflood Management Operations
Hydrocarbon Transport for Sale
Oil/Water Separation
Producing Well
Reservoir
Injection Well
Injection Facilities
Water for Discharge
Wastes for Disposal
Water Treatment
Water Source
Prevention
Understand geology and apply appropriate level of reservoir model Timing to start waterfloodHorizontal wellSmart completions
i-field concept– Instrumentation– Information in real-time– Intervention in real-time– Innovative business
solutions
Diagnosis
Use Existing Data (diagnosis plots)Seismic (3D, 4-D)Interwell TracersLogging – production, nuclear, opticReservoir modelingPressure Well TestingFluid Analysis
Interwell Tracer
How to use it? How to use it? –– Inject into injectorInject into injector–– Collect fluid samples Collect fluid samples
from producersfrom producers–– AnalyzeAnalyze–– Look for breakthrough Look for breakthrough
time and concentrationtime and concentration
What are new?What are new?–– NonNon--radioactiveradioactive–– Highly sensitive (ppb, Highly sensitive (ppb,
ppt) ppt) FBA (water phase)FBA (water phase)PFC (gas phase)PFC (gas phase)
Interwell Tracer
0
10
20
30
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0 10 20Time
Con
cent
ratio
n
Shows multiple paths with relativelevel of permeability and thickness
Chevron Interwell Tracer Studies
Expected the Un-expectedWe have applications in interwell tracer jobsWe have applications in interwell tracer jobs
a)a) Permian Basin, USAPermian Basin, USAb)b) Bakersfield, California USABakersfield, California USAc)c) Indonesia Indonesia d)d) North Sea North Sea e)e) Caspian Sea (gas tracers) Caspian Sea (gas tracers) f)f) Angola Angola
Case 1Geologist and Engineer disagree on fracture connectivity
Tracer BT within 2 days in two distant wells, and long BT time in offset wells: therefore fracture or extremely severe channel
Case 1Geologist and Engineer disagree on fracture connectivity
Tracer BT within 2 days in two distant wells, and long BT time in offset wells: therefore fracture or extremely severe channel
Tracer
2 days2 days
Case 2Relatively Homogenous reservoir: fluid flow direction?
Tracer can show downhole directional fluid flow
Case 2Relatively Homogenous reservoir: fluid flow direction?
Tracer can show downhole directional fluid flow
Surfactant floodSurfactant flood
20 days30 days
> 180 days> 180 days
Case 3multiple tracers for full reservoir monitoring
Breakthrough was 2 years instead of 2 months
Case 4Tracer BT in different reservoir -
hydraulic fracture jobs maybe too aggressive, broke shale break; a lot of bypassed oil
Shale
BA
Interwell TracerGood Practices, and Challenges
1. Define objectives, and design details accordingly2. Appropriate monitor wells – all offset wells, plus others3. Enough tracers to be detectable at the furthest monitor well4. Collaborative QC test (only two labs in the world qualify)5. More frequent fluid samples at the beginning, and less later.6. Collect more samples than needed, but analyze every 5th to
start.
• Challenge: easy way to input to reservoir models
Solution OptionsOthersOthers–– ReRe--completioncompletion–– Horizontal wellHorizontal well–– MultiMulti--lateralslaterals–– SlimSlim--hole completionshole completions–– StimulationStimulation–– Reverse ConingReverse Coning–– InIn--fill Drillingfill Drilling–– Realign waterfloodRealign waterflood–– Single zone Single zone
completionscompletions
Mechanical methodsMechanical methods–– Packers / bridgePackers / bridge--plugsplugs–– StraddleStraddle--packerspackers–– ThruThru--Tubing BridgeTubing Bridge--PlugPlug–– PatchPatch--flex / polyboreflex / polybore–– Downhole SeparatorDownhole Separator–– Selective injection Selective injection
equipmentequipment–– LinersLiners
Solution Options– Foamed gel– Foam– Polymer/surfa
ctant flood – Microbial
CHEMICAL METHODS– Cement– Resin– Gels (ringing, tonguing, flowing)
In-depth Conformance ControlSelective Water shutoff
In-depth Conformance Control Application for Injectors
Polymer of 43000 to 140,000monomer residue units,Molecular weight about 10 x 106
0.3 - 0.5microns
•Small Crosslinked polymer particles•Propagate deep into reservoir •Easily mixed; •Highly expandable with time and temperature change.•Co-developed between Chevron, BP and Nalco: BrightWater TM
What is new?What is new?This is a smart chemical, This is a smart chemical, very different from very different from conventional gelsconventional gels
In-depth water control Application for Injectors – Field result
J FMAMJ J A SOND J FMAMJ J A SOND J FMAMJ J A SOND J FMAMJ J A SOND J FMAMJ J1998 1999 2000 2001 2002
0
200
400
600
800
1000
1200
1400
1600
1800
(1)2000
0
3000
6000
9000
12000
15000
18000
21000
24000
27000
30000(2)
(1)CDOIL (2)CDLIQ VS Time
Group: East_well Wells In Group: 3 Format: monthprod
SPE 84987 and 89391
In-depth Conformance Control
Good Practices and Challenges
1. Select Appropriate candidates – available oil reserves– poor sweep efficiency– reservoir temperature from 20o C (80oF) and 150oC (300oF)– thief zone greater than 100 mD
2. Avoid interwell-fractures.3. Reservoir simulation to predict economics.4. Evaluate interwell transit time.
Challenge: more field tests
Selective Water ShutoffApplication for Producers
ADVANTAGE:ADVANTAGE:••Low cost, does not need rig or CTLow cost, does not need rig or CT••Low risk (does not harm oil zone)Low risk (does not harm oil zone)••Recent field successesRecent field successes
DISADVANTAGE:DISADVANTAGE:••NOT total shutoffNOT total shutoff••NonNon--fractured reservoir onlyfractured reservoir only••Cannot hold back high differential Cannot hold back high differential pressurepressure••May need repeated treatmentsMay need repeated treatments••Bad past experienceBad past experience
Level Raising Coning ChannelingLevel Raising Coning ChannelingLevel Raising Coning Channeling
What are new?What are new?Smart chemicals for selective shutSmart chemicals for selective shut--offoffNine new products being developedNine new products being developedNew lab procedures to evaluateNew lab procedures to evaluate
End-Point Permeability
0
100
200
300
400
500
Specif ic Kw Baseline Koat Sw i
Baseline Kwat Sor
Kw AfterTreatmentCycle 1
Ko AfterTreatmentCycle 1
Kw AfterTreatmentCycle 2
Ko AfterTreatmentCycle 2
Effe
ctive
Perm
eability
to F
luid, m
illida
rcys
Wellbore
Formation
Selective Water ShutoffMany products being marketed, which one to use?
Use Laboratory Test to select and designUse Laboratory Test to select and design
Selective Water ShutoffField Result
Permeability: ~940 mDPermeability: ~940 mDTemperature: 200 FTemperature: 200 F
0
100
200
300
400
500
11/15/2001 12/13/2001 1/10/2002
Dates
BOPD %WC
Some excellent results, butSome excellent results, butoverall industry field results have overall industry field results have been mixed.been mixed.
Selective Water shut-offGood Practices and Challenges
1. Select appropriate candidate – enough remaining oil; – multi-layer sandstone without cross-flow
2. For permeability 5 to 3000 md formation rock. Be careful with clay-rich rock.
3. If needed, use lab test to select product and design concentration.
4. Bullhead to place Selective Water Shut-off treatments, with proper pre-flushes and post-flushes.
5. Treat 5 to 8 feet (2 to 3 meters) beyond well-bore.
Challenges: select appropriate product and concentration.
Phase 1. Establish Asset Strategy for Water Control
Phase 1. Establish Asset Strategy for Water Control
Tasks:•
Tasks:•
Outcome: Water control strategy
Outcome: Water control strategy
Phase 2. Identify and Evaluate the Problem
Phase 2. Identify and Evaluate the Problem
Phase 3. Identify the Options
Phase 3. Identify the Options
Phase 4. Implement
Phase 4. Implement
Phase 5. Monitor and Evaluate
Phase 5. Monitor and Evaluate
Tasks:•
Tasks:•
Tasks:•
Tasks:•
Tasks:•
Tasks:•
Tasks:•
Tasks:•
Outcome: Problem and source identified
Outcome: Problem and source identified
Outcome: Option selected
Outcome: Option selected
Outcome: Job executed
Outcome: Job executed
Outcome: Results documented and shared
Outcome: Results documented and shared
Water Control ProcessWater Control Process
Conclusions
Oil/gas are most importantOil/gas are most importantPrevention is important for new fieldsPrevention is important for new fieldsDiagnosis: new nonDiagnosis: new non--radioactive interwell tracersradioactive interwell tracersChemical solutions: InChemical solutions: In--depth conformance depth conformance control for injectors, and selective watercontrol for injectors, and selective water--shutoff shutoff for producersfor producersGood Practices and Challenges; field resultsGood Practices and Challenges; field resultsIntegrated the skills, process (strategy, diagnosis, Integrated the skills, process (strategy, diagnosis, options, implement and monitor).options, implement and monitor).
The Latest in Ways to Improve Asset Value Through Better Water Management
Thanks You!
Questions and Discussions?
Steve CheungChevron Energy Technology Company
1-510-242-1624 office or 1-714-924-2228 mobile
