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INTEGRATED PROCESSES FOR TREATMENT OF BERKELEY PIT WATER
INTEGRATED PROCESSES FOR TREATMENT OF BERKELEY PIT WATER
ACTIVITY III, PROJECT 21
BACKGROUNDBACKGROUND
The Berkeley Pit (Butte, Montana) - is currently filling at a rate of 3 million gallons per day of acidic, metals laden water
EPA issued a Record of Decision in 1994; the Berkeley Pit will be allowed to fill until approximately 2021, at which time the water level will approach the Critical Water Level
BACKGROUND (cont.)BACKGROUND (cont.)
Treatment technologies will be revisited approximately 2009; treatment required essentially forever
ROD designated hydroxide precipitation with aeration (followed by reverse osmosis if necessary) as preferred treatment technology
Over 1000 tons per day of dewatered sludge will be produced
PROJECT CONCEPTPROJECT CONCEPTValue of contained metals presents opportunity for
offsetting treatment costs via product recovery/resale
Acid mine drainage a worldwide problem
Project will evaluate both proven and new technologies for optimizing overall economics of producing compliant water
PROJECT CONCEPT (Cont’d.)PROJECT CONCEPT (Cont’d.)
All aspects of problem will be included
ChallengesDistance of Butte, Montana from marketsDilute feed stream (though extremely contaminated) Low-value base metals present
CURRENT PROJECT SCOPECURRENT PROJECT SCOPE
Develop two optimized flowsheets Water Treatment-Only Water Treatment-Plus-Product Recovery If results economically attractive, pursue pilot testing of optimized product recovery process at Berkeley Pit
CURRENT PROJECT SCOPE (Cont’d.)CURRENT PROJECT SCOPE (Cont’d.)
Major TasksPrepare standardized cost-estimating methodologyDevelop optimization strategy (identify/prioritize potential process improvements)
PROJECT STATUS AS OF APRIL 2000PROJECT STATUS AS OF APRIL 2000
Work plan complete Conceptual design of sludge repository complete Cost estimating methodology document complete Document verifying technical and cost aspects of
reference flowsheets complete Optimization strategy in development Preliminary optimization efforts underway (gathering
cost/technical data applicable to both flowsheets)
PROJECT SCHEDULEPROJECT SCHEDULE
Final report describing optimized flowsheets due for publication in November 2000
IMPROVEMENTS IN ENGINEERED BIOREMEDIATION OF ACID MINE DRAINAGE
Activity III, Project 24
IMPROVEMENTS IN ENGINEERED BIOREMEDIATION OF ACID MINE DRAINAGE
Activity III, Project 24
Project ObjectivesProject Objectives Objectives for improvements of engineered features of a passive SRB-bioreactor include:Selection of media Design of a permeability and contact time
enhancing system (PACTES),Design of an organic carbon replaceable
cartridge system (RCS),Development of computer software to model
SRB bioremedial processes in the bioreactor.
Scope of WorkScope of Work
The scope of work of the project includes seven tasks:
Task ISelection of organic carbon media that:
is permeable when saturated with water,
contains sufficient mass of organic carbon to minimize treatment rates, and
Could be economically used for passive SRB bioreactors.
Scope of Work, cont.Scope of Work, cont.
Task II PACTES design, evaluation through a bench test
study, and implementing it in the field.
Task III Designing of an organic carbon RCS that would
be easy to install and replace in a bioreactor at a remote location.
Scope of Work, cont.Scope of Work, cont.
Task IV
Development or adaptation of computer software to model SRB bioremedial processes in the bioreactor.
This task includes efforts on: Software development and validation Lab experiments for bioreaction kinetics
Scope of Work, cont.Scope of Work, cont.
Task V Implementation of the results of the four
previous tasks in a bioreactor constructed for this purpose.
Task VI Project management activities.
Task VII Site selection and characterization
Status of Work(as of 03/31/00)Status of Work(as of 03/31/00)
Task I was initiated in February, 2000.
Data base structure is 60% developed.
Search of information is advanced approximately 30%.
SLUDGE STABILIZATIONSLUDGE STABILIZATION
Activity IV ; Project 2
OBJECTIVEOBJECTIVEFormation, properties and stability of sludge
generated during treatment of acid mine waste waterPhysically and chemically characterize sludgesStudy the stability of sludges created by treatment
techniquesApply to acid mine water
Point sourceNon-point source
Stabilization Techniques will be Developed for Hazardous Sludge
Stabilization Techniques will be Developed for Hazardous Sludge
Commonly used additives for metallurgical waste solids
Thermal ProcessingEffective for arsenic bearing waste
Recovery of metal values or removal of hazardous constituent/recycling to metallurgical processes
In particular, sulfide sludge
DEMONSTRATION OF ARSENIC REMOVAL TECHNOLOGY
DEMONSTRATION OF ARSENIC REMOVAL TECHNOLOGY
Activity IV ; Project 5
OBJECTIVESOBJECTIVES
Remove Arsenic from Solution
Characterize Solid Products
Determine Stability During Storage
CONCEPTCONCEPT
Produce an apatite mineral-like structure with the substitution of arsenate for phosphate in the structure
REMOVAL OF ARSENIC FROM WASTE SOLUTIONSREMOVAL OF ARSENIC FROM WASTE SOLUTIONS
WHAT IS WRONG WITH SIMPLE LIME PRECIPITATION??
EPA’s BDAT FOR As BEARING WASTEWATERSEPA’s BDAT FOR As BEARING WASTEWATERS
Ferrihydrite precipitation is an adsorption phenomena
Potential ProblemLong-term storage
ASARCO DEMO RESULTSASARCO DEMO RESULTS
Scrubber Blowdown Water>3,000,000 ppb As to <10ppb As
Thickener Overflow6,000 ppb As to <15 ppb
Long-term Aging Presently Being Conducted (ASARCO and Mineral Hill Products)
MINE WASTE BERKLEY PIT LAKE CHARACTERIZATION PROJECT
MINE WASTE BERKLEY PIT LAKE CHARACTERIZATION PROJECT
Activity IV ; Project 8
CHARACTERIZATION PROJECTSCHARACTERIZATION PROJECTS
DEPTH PROFILESORGANIC CARBONSRB ACTIVITY IN SEDIMENTSSURFACE WATER REACTION KINETICS
SUMMARYSUMMARY
Berkley Pit Lake system is complex and requires much more research to fully understand
Knowledge gained through work on Berkley Pit may be used on other pit lakes through out the world
Artificial Neural Networks As An Analysis Tool for Geochemical Data
Artificial Neural Networks As An Analysis Tool for Geochemical Data
Activity IV ; Project 14
WHY USE NEURAL NETWORK?
TO SORT THROUGH OR ANALYZE VERY LARGEDATA VOLUMES
NN’s basically think like the human brain
ALGAL REMEDIATION DATA OF BERKELEY PITALGAL REMEDIATION DATA OF BERKELEY PIT
4 Classes of Data with 15 SamplesWithin each class, 5 subclasses exist with
3 samples each
Self- Organizing MapSelf- Organizing Map
Groups Data According to Trends Within the Data
For Algae, the SOM Output Compared to Known Data Classes
NOTE: Neural Networks can also be used to predict data
Future Possibilities for NN Analysis of AlgaeFuture Possibilities for NN Analysis of Algae
Look for behavior trend within Algae speciesCompare similarities and differencesTrain network to recognize different Algae
species and concentrationsDevelop network to predict Algae types and
concentrations from pit-water metal concentrations