Controlled Bioreactor Landfill Program at the Yolo County ... · Controlled Bioreactor Landfill...
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©2007 Yolo County Yazdani©2007 Yolo County Yazdani
Controlled Bioreactor Landfill Controlled Bioreactor Landfill Program at the Program at the
Yolo County Central LandfillYolo County Central Landfill
Ramin Ramin YazdaniYazdani, Jeff Kieffer, Kathy Sananikone, Jeff Kieffer, Kathy SananikoneYolo County Planning and Public Works DepartmentYolo County Planning and Public Works Department
Division of Integrated Waste Management Division of Integrated Waste Management Woodland, California U.S.Woodland, California [email protected]@yolocounty.org
(530) 666(530) 666--88488848
Methane to Markets Partnership ExpoMethane to Markets Partnership Expo30 October30 October--1 November 2007 1 November 2007
Beijing, ChinaBeijing, China
©2007 Yolo County Yazdani©2007 Yolo County Yazdani
Presentation OutlinePresentation Outline
Research objectivesResearch objectivesIntroductionIntroductionExperimental facilitiesExperimental facilitiesProject resultsProject resultsProject findings/conclusionsProject findings/conclusionsAcknowledgmentsAcknowledgments
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Research ObjectivesResearch Objectives
Accelerate waste decomposition, waste Accelerate waste decomposition, waste settlement and maximize methane settlement and maximize methane capture.capture.Analyze the data gathered from fullAnalyze the data gathered from full--scale scale landfill bioreactors.landfill bioreactors.Asses the economic benefits of landfill Asses the economic benefits of landfill bioreactor versus conventional landfilling.bioreactor versus conventional landfilling.Asses the potential carbon impacts of Asses the potential carbon impacts of bioreactor landfill.bioreactor landfill.
©2007 Yolo County Yazdani©2007 Yolo County Yazdani
Degradable Organic Waste Degradable Organic Waste Landfilled in U.S.Landfilled in U.S.
0102030405060708090
Before Recycling After Recycling
Paper & paperboard Yard Trimmings Food Waste
84.5 million tons36.5% of generated140.3 million tons
60.5% of generated
Total waste generated = 231.9 million tonsSource: Franklin Associates (EPA-530-R-02-001), Table ES-4, page 7, 2003
(mill
ion
tons
)
©2007 Yolo County Yazdani©2007 Yolo County Yazdani
Conventional “Dry” LandfillsConventional “Dry” Landfills
Vegetative Cover
Compacted Clay Cover
Gas Collection
Compacted Clay Geomembrane
Waste Daily CellLeachate Collection
Layer
Native Soil
©2007 Yolo County Yazdani©2007 Yolo County Yazdani
Objectives of Current Objectives of Current Conventional “Dry” LandfillsConventional “Dry” Landfills
Subtitle D of Resource Conservation and Subtitle D of Resource Conservation and Recovery Act (40 CFR part 258)Recovery Act (40 CFR part 258)
Minimize the amount of moisture in Minimize the amount of moisture in landfilllandfillMinimize the risk of groundwater Minimize the risk of groundwater pollutionpollutionLimits the amount of leachate and gas Limits the amount of leachate and gas generatedgenerated
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Problems with Conventional Problems with Conventional “Dry” Landfilling“Dry” Landfilling
Waste decomposition at suboptimal rates.Waste decomposition at suboptimal rates.Waste remains undecomposed for decades Waste remains undecomposed for decades to even centuries.to even centuries.Leachate and gas generation (50% CHLeachate and gas generation (50% CH44, , 50% CO50% CO22) persist long into the future.) persist long into the future.LongLong--term management and monitoring of term management and monitoring of landfills issues.landfills issues.
©2007 Yolo County Yazdani©2007 Yolo County Yazdani
Landfills Contribute to Landfills Contribute to Greenhouse GasesGreenhouse Gases
Methane is 20 times more damaging than Methane is 20 times more damaging than carbon dioxide on a volume basis (USEPA, carbon dioxide on a volume basis (USEPA, 1994).1994).Landfills are responsible for 8% of total Landfills are responsible for 8% of total anthropogenic methane released (based anthropogenic methane released (based on EPA estimates).on EPA estimates).Landfill gas is also a renewable energy Landfill gas is also a renewable energy source.source.
©2007 Yolo County Yazdani©2007 Yolo County Yazdani
Bioreactor Landfill DefinitionBioreactor Landfill Definition
“a bioreactor landfill is a controlled “a bioreactor landfill is a controlled landfill or landfill cell where liquid and gas landfill or landfill cell where liquid and gas conditions are actively managed in order conditions are actively managed in order to accelerate or enhance biostabilization of to accelerate or enhance biostabilization of the waste.”* the waste.”*
**As defined by the Solid Waste Association of North America (SWANAs defined by the Solid Waste Association of North America (SWANA)A)
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What’s different about a What’s different about a Controlled Bioreactor Landfill?Controlled Bioreactor Landfill?
Controlled quantities of liquid added Controlled quantities of liquid added and recirculatedand recirculated
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Landfill Gas Generation CurvesLandfill Gas Generation Curves
02468
101214161820
0 5 10 15 20 25 30
Time (Years)
Gas
Pro
duct
ion
(SC
FM)
Bioreactor Landfill
Conventional Landfill
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Phases of Decomposition in Phases of Decomposition in Bioreactor LandfillsBioreactor Landfills
Aerobic phaseAerobic phaseAnaerobic acid phaseAnaerobic acid phaseAccelerated methane production phaseAccelerated methane production phaseDecelerated methane production phaseDecelerated methane production phase
02468
101214161820
0 5 10 15 20 25 30
Time (Years)
Gas
Pro
duct
ion
(SC
FM)
Bioreactor Landfill
Conventional Landfill
©2007 Yolo County Yazdani©2007 Yolo County Yazdani
Important Factors in Important Factors in Biodegradation of WasteBiodegradation of Waste
Moisture contentMoisture contentTemperatureTemperaturepHpHNutrientsNutrientsParticle sizeParticle sizeToxinsToxins
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“COOL”
Temperature Dependence of Methanogenesis
60°C (140°F) is > 20 times FASTER THAN 20ºC (68ºF)
“Hot”
K = K0 e –E/RT
Rat
e Co
nsta
nt, K
(da
ys)
-1
“Cold”
Ashare E., et al., 1978 “Methane production from animal residue”, By Dynatech. R&D Report for U.S. DOE (ERDA)
©2007 Yolo County Yazdani©2007 Yolo County Yazdani
Bioreactor Landfill Potential Bioreactor Landfill Potential BenefitsBenefits
Maximizing landfill gas capture for renewable energy (anaerobic).Rapid organic waste conversion & stabilization.Increased landfill space capacity reuse.Reduction of post-closure care maintenance and future risk.Improved leachate treatment.Reduction of landfill gas fugitive emissions.Carbon sequestration potential (anaerobic).
©2007 Yolo County Yazdani©2007 Yolo County Yazdani
Experimental Facilities: Experimental Facilities: Bioreactor Research CellsBioreactor Research Cells
8,000 tons control cell “dry cell” (0.25 acre)8,000 tons control cell “dry cell” (0.25 acre)8,000 tons anaerobic bioreactor cell (0.25 acre)8,000 tons anaerobic bioreactor cell (0.25 acre)76,000 tons anaerobic bioreactor cell (3.5 acres)76,000 tons anaerobic bioreactor cell (3.5 acres)194,000 tons anaerobic bioreactor cell (6.0 194,000 tons anaerobic bioreactor cell (6.0 acres)acres)15,000 tons aerobic bioreactor cell (2.5 acres)15,000 tons aerobic bioreactor cell (2.5 acres)
©2007 Yolo County Yazdani©2007 Yolo County Yazdani
Location of Research FacilitiesLocation of Research Facilities
3 miles
Yolo County Central Landfill
Davis, CA.
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Experimental Landfill Experimental Landfill Bioreactors Cell ComponentsBioreactors Cell Components
Operational flow diagramOperational flow diagramWaste containment facilitiesWaste containment facilitiesInIn--situ instrumentationssitu instrumentationsLandfill gas collection and removal systemLandfill gas collection and removal systemLeachate injection and recirculation systemLeachate injection and recirculation systemLandfill cover systemLandfill cover systemData monitoring and collection systemData monitoring and collection system
©2007 Yolo County Yazdani©2007 Yolo County Yazdani
Operational Flow Diagram for Operational Flow Diagram for Bioreactor CellsBioreactor Cells
Control Cell Enhanced Cell
Anaerobic Bioreactor Research Cell - 8,000 tons
Leacha
Leac
hate
in
Gas out
InstrumentationInstrumentation
Leachate out
Leakage out
Leachate out
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Experimental Landfill Experimental Landfill BioreactorsBioreactors
Control Cell Enhanced Cell
InstrumentationInstrumentation
CoverCoverRemote Telemetry Unit
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Experimental Landfill Bioreactor Experimental Landfill Bioreactor CellsCells
3.5 acreAnaerobicBioreactor
6.0 acreAnaerobicBioreactor
2.5 acreAerobicBioreactor
©2007 Yolo County Yazdani©2007 Yolo County Yazdani
Waste Containment FacilitiesWaste Containment Facilities
Construction of base liner systemConstruction of base liner system
In-situ waste temperature, waste moisture, and liquid/gas pressure
Leachate pumping andsampling location
©2007 Yolo County Yazdani©2007 Yolo County Yazdani
Over 400 instruments and 20 miles of wires were Over 400 instruments and 20 miles of wires were installed in the landfill for collecting data.installed in the landfill for collecting data.
InIn--situ Instrumentation situ Instrumentation
©2007 Yolo County Yazdani©2007 Yolo County Yazdani
Waste Placement in Waste Placement in Experimental CellsExperimental Cells
Construction of landfill waste filling Construction of landfill waste filling
2’ protective recycledShredded tires
Compacted waste lift
©2007 Yolo County Yazdani©2007 Yolo County Yazdani
Experimental Landfill Cell Experimental Landfill Cell CrossCross--sectional Viewsectional View
Total Waste = 79,164 tons
Reinforced PolypropyleneSurface Liner
Instrumentation Layer 3
Instrumentation Layer 2
Instrumentation Layer 1
Instrumentation Base Layer
Waste Lift 3
Waste Lift 2
Waste Lift 1
Lift 4
Leachate InjectionGas Collection
©2007 Yolo County Yazdani©2007 Yolo County Yazdani
Landfill Gas Collection SystemLandfill Gas Collection System
Over 12,000 feet of piping for gas collection Over 12,000 feet of piping for gas collection and removal system was installed.and removal system was installed.
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Landfill Gas Collection and Landfill Gas Collection and Removal SystemRemoval System
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Leachate Injection and Leachate Injection and Recirculation SystemRecirculation System
Over 17,000 feet of piping for leachate injection Over 17,000 feet of piping for leachate injection and recirculation was installed.and recirculation was installed.
©2007 Yolo County Yazdani©2007 Yolo County Yazdani
Construction of Cover SystemConstruction of Cover System
Over 500,000 square feet synthetic landfill Over 500,000 square feet synthetic landfill liner (HDPE) was installed.liner (HDPE) was installed.
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Installed Cover SystemInstalled Cover System
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Data Monitoring and Collection Data Monitoring and Collection SystemSystem
Supervisory Control and Data Supervisory Control and Data Acquisition (SCADA) SystemAcquisition (SCADA) System
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SCADA computer screenSCADA computer screen
Data Monitoring and Collection Data Monitoring and Collection SystemSystem
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Waste Sampling & TestingWaste Sampling & Testing
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Automated Data Collection Automated Data Collection System System (monitored continuously)(monitored continuously)InIn--situ Measurements situ Measurements
Waste temperature (degree C)Waste temperature (degree C)Moisture sensor (% saturation)Moisture sensor (% saturation)Static head on the base liner (ft)Static head on the base liner (ft)
Volume of leachate added and recirculated Volume of leachate added and recirculated (gallons)(gallons)Volume of landfill gas collected (scfm)Volume of landfill gas collected (scfm)Mass and type of waste and cover soil (tons)Mass and type of waste and cover soil (tons)
©2007 Yolo County Yazdani©2007 Yolo County Yazdani
Bioreactor Landfill Leachate Quality Bioreactor Landfill Leachate Quality Monitoring ParametersMonitoring Parameters
ParametersParameters Monitoring Frequency (1Monitoring Frequency (1stst//22ndnd yr)yr)
Temperature (Temperature (°°C)C) MonthlyMonthlypHpH MonthlyMonthlyConductivity (Conductivity (µµSm/cm)Sm/cm) MonthlyMonthlyBiochemical Oxygen Demand (mg/L)Biochemical Oxygen Demand (mg/L) Monthly/QuarterlyMonthly/QuarterlyChemical Oxygen Demand (mg/L)Chemical Oxygen Demand (mg/L) Monthly/QuarterlyMonthly/QuarterlyDissolved Oxygen (mg/L)Dissolved Oxygen (mg/L) Monthly/QuarterlyMonthly/QuarterlyDissolved Solids (mg/L)Dissolved Solids (mg/L) Monthly/Monthly/ QuarterlyQuarterlyTotal Organic Carbon (mg/L)Total Organic Carbon (mg/L) Monthly/QuarterlyMonthly/QuarterlyNutrients (NHNutrients (NH33, TKN, TP) (mg/L), TKN, TP) (mg/L) Monthly/Monthly/ QuarterlyQuarterlyCommon ions (mg/L)Common ions (mg/L) Monthly/QuarterlyMonthly/QuarterlyHeavy metal (mg/L) Heavy metal (mg/L) Monthly/Monthly/ QuarterlyQuarterlyOrganic priority pollutants (Organic priority pollutants (µµg/L)g/L) Monthly/QuarterlyMonthly/Quarterly
©2007 Yolo County Yazdani©2007 Yolo County Yazdani
Analytical Parameters MonitoredAnalytical Parameters MonitoredParametersParameters Monitoring FrequencyMonitoring FrequencyLandfill Gas Landfill Gas
CHCH44, CO, CO22, O, O22, N, N22, CO (%V/V), CO (%V/V) WeeklyWeeklyNMOC (%V/V)NMOC (%V/V) Monthly/QuarterlyMonthly/QuarterlyHH22S (%V/V)S (%V/V) Monthly/QuarterlyMonthly/QuarterlyNN22O (%V/V)O (%V/V) Monthly/QuarterlyMonthly/Quarterly
Solids TestingSolids TestingMoisture content (% M/M)Moisture content (% M/M) AnnuallyAnnuallyVolatile solids (% M/M)Volatile solids (% M/M) AnnuallyAnnuallyMethane yield (mL CHMethane yield (mL CH44/g)/g) AnnuallyAnnuallyCellulose (% M/M)Cellulose (% M/M) AnnuallyAnnuallyLignin (% M/M)Lignin (% M/M) AnnuallyAnnually
Landfill Settlement Landfill Settlement Topographic survey Topographic survey AnnuallyAnnually
©2007 Yolo County Yazdani©2007 Yolo County Yazdani
Bioreactor Research QuestionsBioreactor Research Questions(partial list)(partial list)
Does operation of a landfill as a bioreactor:Does operation of a landfill as a bioreactor:Enhance the rate of methane production compared to a Enhance the rate of methane production compared to a conventional “dry” landfill? conventional “dry” landfill? Increase waste settlement and volume loss?Increase waste settlement and volume loss?Improve leachate quality?Improve leachate quality?Increase moisture content to optimum level?Increase moisture content to optimum level?Reduce refuse stabilization time?Reduce refuse stabilization time?Increase the benefitIncrease the benefit--cost ratio when compared with a cost ratio when compared with a conventional “dry” landfill?conventional “dry” landfill?
©2007 Yolo County Yazdani©2007 Yolo County Yazdani
Methane Generation CurvesMethane Generation Curves
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
Jun-96
Feb-97
Oct-97
Jun-98
Feb-99
Nov-99
Jul-00
Mar-01
Nov-01
Jul-02
Apr-03
Dec-03
Aug-04
Apr-05
Dec-05
Sep-06
May-07
Jan-08
Date
Cum
ulat
ive
Met
hane
Vol
ume
(scf
/dry
lbs
was
te)
Conventional Landfill Range 8,000 tons Enhanced 8,000 tons Control
(scf
/dry
lb w
aste
)
©2007 Yolo County Yazdani©2007 Yolo County Yazdani
Methane Generation CurvesMethane Generation Curves
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
Jun-96
Feb-97
Oct-97
Jun-98
Feb-99
Nov-99
Jul-00
Mar-01
Nov-01
Jul-02
Apr-03
Dec-03
Aug-04
Apr-05
Dec-05
Sep-06
May-07
Jan-08
Date
Cum
ulat
ive
Met
hane
Vol
ume
(scf
/dry
lbs
was
te)
Conventional Landfill Range 8,000 tons Enhanced 8,000 tons Control
Water leaked intothe control cell
(scf
/dry
lb w
aste
)
©2007 Yolo County Yazdani©2007 Yolo County Yazdani
Methane Generation CurvesMethane Generation Curves
0.00.10.20.30.40.50.60.70.80.91.01.11.21.31.41.5
0 200 400 600 800 1000 1200 1400 1600 1800 2000
Time (days following the beginning of liquid addition)
Cum
ulat
ive
Met
hane
Vo
lum
e (s
cf/d
ry lb
. was
te)
3.5-Acre Cell 6-Acre Cell Conventional Dry Landfill 8,000 ton Anaerobic Cell
©2007 Yolo County Yazdani©2007 Yolo County Yazdani
Fitted 1Fitted 1stst Order Kinetic Rate Order Kinetic Rate CoefficientsCoefficients
-3.0
-2.5
-2.0
-1.5
-1.0
-0.5
0.0
0 1 2 3 4 5 6 7 8
Years
Ln(L
/Lo)
3.5-Acre Cell 6-Acre Cell 8,000 tons Cell
K= 0.38 yr-1
R2 = 0.9416
K= 0.14 yr-1
R2 = 0.99
K= 0.25 yr-1
R2 = 0.98
L is volume of methane remaining to be produced after time tL0 is maximum volume of methane (SCF/dry pounds). L0 = 1.5 scf/dry lbs
©2007 Yolo County Yazdani©2007 Yolo County Yazdani
Project FindingsProject Findings
Liquid addition and recirculation in all anaerobic Liquid addition and recirculation in all anaerobic bioreactor cells increased first order rate bioreactor cells increased first order rate constant by factor of three to as much as constant by factor of three to as much as eightfold over “typical” landfill experience. This eightfold over “typical” landfill experience. This method of operation will result in early method of operation will result in early completion of organic waste decompositioncompletion of organic waste decomposition. .
Methane capture efficiency can be increased Methane capture efficiency can be increased significantly when waste is covered quickly with significantly when waste is covered quickly with a synthetic cover.a synthetic cover.Enhanced methane capture results in reduction Enhanced methane capture results in reduction of global warming impacts. of global warming impacts.
©2007 Yolo County Yazdani©2007 Yolo County Yazdani
Waste Settlement DataWaste Settlement Data
0%2%4%6%
8%10%12%14%
16%18%20%
0 1 2 3 4 5 6 7
Time (Yr)
Set
tlem
ent (
%)
3.5-Acre Cell 8,000 tons Cell 8,000 tons Control 6-Acre Cell
©2007 Yolo County Yazdani©2007 Yolo County Yazdani
8,000 ton Control and Enhanced 8,000 ton Control and Enhanced Experimental CellsExperimental Cells
Control Cell(background)
2007 Photo
Enhanced Cell
20% settlement (~10 ft)
©2007 Yolo County Yazdani©2007 Yolo County Yazdani
FindingsFindings
Liquid addition and recirculation in all Liquid addition and recirculation in all anaerobic bioreactor cells increased anaerobic bioreactor cells increased settlement by factor of two to as much as settlement by factor of two to as much as fivefold over a conventional “dry” landfill.fivefold over a conventional “dry” landfill.The additional air space gained is The additional air space gained is estimated to yield a revenue of $80,000 to estimated to yield a revenue of $80,000 to $100,000 per acre per ft.$100,000 per acre per ft.
©2007 Yolo County Yazdani©2007 Yolo County Yazdani
FindingsFindings
Parasitic energy use is less than 2% of gross Parasitic energy use is less than 2% of gross methane energy produced. Typical in vessel methane energy produced. Typical in vessel digester parasitic energy use is in 30digester parasitic energy use is in 30--40%. 40%. Net cost is $1 to $4 per ton of waste (large vs. Net cost is $1 to $4 per ton of waste (large vs. small landfill). If assigned to fuel, equivalent to small landfill). If assigned to fuel, equivalent to $6 to $30 per equivalent barrel of oil.$6 to $30 per equivalent barrel of oil.Volume reduction and landfill life extension Volume reduction and landfill life extension alone can yield revenue to justify controlled alone can yield revenue to justify controlled bioreactor landfill.bioreactor landfill.
©2007 Yolo County Yazdani©2007 Yolo County Yazdani
FindingsFindings
If bioreactor technology is applied to 50If bioreactor technology is applied to 50--75% of 75% of US waste:US waste:
Fugitive methane emission < 5%Fugitive methane emission < 5%--10% of generated.10% of generated.Increased recovered methane by 30Increased recovered methane by 30--100%; potential 100%; potential for 100,000for 100,000--200,000 daily barrel oil equivalent.200,000 daily barrel oil equivalent.Greenhouse benefits for US ~50Greenhouse benefits for US ~50--100+ million tons 100+ million tons COCO22 equivalent at cost of $1equivalent at cost of $1--$5 per ton CO$5 per ton CO22equivalent.equivalent.
Reference: IEM, 1999. Landfill Operation for Carbon SequestratioReference: IEM, 1999. Landfill Operation for Carbon Sequestration and Greenhouse Gas Mitigation, n and Greenhouse Gas Mitigation, for National Energy Technology Laboratory, US DOE, Program DEfor National Energy Technology Laboratory, US DOE, Program DE--AC26AC26--98FT40422.98FT40422.
©2007 Yolo County Yazdani©2007 Yolo County Yazdani
ConclusionsConclusions
Substantial acceleration of methanogenesis and Substantial acceleration of methanogenesis and decomposition, over fivefold (k>0.4decomposition, over fivefold (k>0.4--0.5 year0.5 year--11) by ) by moisture addition and recirculation.moisture addition and recirculation.Efficient gas capture (>95%) using permeable layer Efficient gas capture (>95%) using permeable layer under synthetic membrane.under synthetic membrane.Can maximize landfill gas energy recovery predictability Can maximize landfill gas energy recovery predictability compared to conventional practice, minimal fugitive compared to conventional practice, minimal fugitive emissions.emissions.Avoid low permeability daily cover soil to ensure uniform Avoid low permeability daily cover soil to ensure uniform moisture distribution.moisture distribution.Control cell (“dry”) results strongly validate “dry tomb” Control cell (“dry”) results strongly validate “dry tomb” and it’s problems.and it’s problems.
©2007 Yolo County Yazdani©2007 Yolo County Yazdani
Research FundingResearch Funding
Yolo County Public WorksYolo County Public Works--Division of Division of Integrate Waste ManagementIntegrate Waste ManagementCalifornia Energy CommissionCalifornia Energy Commission--Public Interest Public Interest Energy Research Energy Research California Integrated Waste Management California Integrated Waste Management Board Board U.S. Department of EnergyU.S. Department of Energy--National Energy National Energy Technology LaboratoryTechnology LaboratoryWestern Regional Biomass Energy ProgramWestern Regional Biomass Energy Program
©2007 Yolo County Yazdani©2007 Yolo County Yazdani
AcknowledgmentsAcknowledgments
Research partners:Institute for Environmental Management, Don Augenstein, President University of Delaware, Professor Paul ImhoffNorth Carolina State University, Professor Morton Barlaz
©2007 Yolo County Yazdani©2007 Yolo County Yazdani
Thank youThank you
Questions?Questions?