A Mid-sized WWTP’s JouJou ey to e gy depe de cerney to Energy … 2010/Dale Doerr_NBP...
Transcript of A Mid-sized WWTP’s JouJou ey to e gy depe de cerney to Energy … 2010/Dale Doerr_NBP...
A Mid-sized WWTP’s Journey to Energy IndependenceJou ey to e gy depe de ce
Sheboygan, WI Experience with CHP
Dale Doerr, SuperintendentSheboygan Regional Wastewater Treatment PlantSheboygan Regional Wastewater Treatment Plant
NBP Webcast
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September 22, 2010
Agendag• Sheboygan Regional WWTP• Why CHP• CHP Performance • Benefits of CHP• Lessons Learned• Lessons Learned• Optimizing Biogas Production• What’s Next• Questions
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Sheboygan Regional WWTP • Built 1982 • 18.4 MGD Permitted Flow• 11 0 MGD Average Flow11.0 MGD Average Flow• Serves 68,000 People
– City of Sheboygan– City of Sheboygan Falls– Village of Kohler– Town of Lima– Town of Sheboygan– Town of Sheboygan FallsTown of Sheboygan Falls– Town of Wilson
• 2009 – Operating Budget $ 3.99Mp g g $– Debt Service $ 355K– Capital Outlay $ 710K– Energy Costs $ 328K
33333 Lakeshore Drive
Sheboygan Regional WWTP• Preliminary/Primary Treatment
– Screening – Grit RemovalGrit Removal– Primary Clarifiers
• Two Treatment Trains– Biological Nutrient Removal– Aeration Basins
• Fine Bubble Membrane Diffusers• High Efficiency Turblex® Blower
– Final Clarifiers– Chlorine Disinfection– Dechlorination– Anaerobic Digestion
• Methane Gas Recovery CHP• Methane Gas Recovery, CHP– Gravity Belt Thickening– Bio-solids Storage 6 - MG– Bio-solids are Land Applied
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Wastewater Treatment Plant Staff
PlantSuperintendent
Staffed HoursMon – Fri :6:00 AM – 6:00 PMS t S 6 00 AM 2 00 PM
Clerk Industrial WasteChemist
Industry
Sat – Sun 6:00 AM – 2:00 PM
y
Operations (5)
MaintenanceSupervisorOperator III Operator III
Laboratory (1)
LaboratoryTechnician
Maintenance (7)
Operator IOperator III
ElectronicsTechnician Electrician
MaintenanceTechnician
MaintenanceTechnicianOperator I
5MaintenanceTechnician Janitor
Operator I
Why CHP?• Waste Heat Study in 2003
• Alliant Energy Power Plant Next DoorAlliant Energy Power Plant Next Door• 250,000 gpm of hot water discharged to Lake Michigan
• Use for excess biogasFlaring 50 000 ft3 of biogas per day• Flaring 50,000 ft3 of biogas per day
• Experiences with a Reciprocating Engine• Fuel CellsFuel Cells• Micro-Turbine Technology• Alliant Energy offers to pay for electrical generationAlliant Energy offers to pay for electrical generation
portion of Micro-turbine Installation
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Cogeneration Project• Startup February 15, 2006
Outside Temperature 20° F– Outside Temperature - 20° F• Installed
• 10 – 30 KW Capstone Micro-turbines• Gas Compression Gas Filtration System• 2 – Cain Heat Exchangers• Piping and Pumps to Utilize Heat Generated by
Micro-turbines• Monitoring and Control System
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Cogeneration Project
10 - 30 kW Capstone Micro-turbines
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10 30 kW Capstone Micro turbines
Cogeneration Project
9Biogas Gas Conditioning (moisture removal, compression and carbon filters)
Cogeneration Project
10Electrical Switch Gear and Power Monitors
Cogeneration ProjectHeat Recovery - Cain Heat Exchangers
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Cogeneration Project
Hot Water Loop Recirculation Pumps
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Cogeneration Project
13January 16, 2008
Facility:
Part 1 - Summary of Prime Mover Electrical Output Part 2 - Description of CHP Prime Mover
Sheboygan Regional Wastewater Treatment Plant
Digester-Gas-Fueled Combined Heat and Power Performance Data Sheet
Respondent: Dale L. Doerry p p
2/15/2006241242
95%97%
Mechanical Capacity (hp):Installation Date:
Plant Flow (MGD):
Digester Gas Capacity (scfm):
97%97%
100%
11.775
Model Number:Electrical Capacity (kW):
Manufacturer:CHP Prime Mover:
(% of Full Load) Capstone Micro-turbine Corporation10 - 30 kW Micro-turbines Date:
p
Electrical Output(kW)
2/5/2010
490,000
Net Electrical Output
239241250
300C-30
Part 3 - Prime Mover - Photograph Part 5 - Prime Mover and Appurtenant Equipment - Process Flow Diagram
24195%
Uptime 87.4%Return to InstructionsReturn to Instructions
Part 4 - Prime Mover - System Description
10 - 30 kW Capstone Micro-turbines with a custom gas conditioning - Gas compression skid built by Unison Solutions, 2 - heat exchangers for heatrecovery built by Cain Industries and electrical switchgear with power grid lockout
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recovery built by Cain Industries, and electrical switchgear with power grid lockout.
Part 6 - Operation and Limitations
Change out the inlet air filters on the micro-turbines and replace the disposable carbon media (for siloxane removal) every 10 weeks Electrical energy (kW) drops when ambient temperature gets above 60 degrees. During cold weather the micro-turbine electrical output is 30 kW each unit, As the ambient air temperature increases to 75 - 80 degrees the micro-turbine kW output drops 22 kW each unit.
Facility:
Date: 2/5/2010
Sheboygan Regional Wastewater Treatment Plant
Respondant: Dale L. DoerrReturn to InstructionsReturn to Instructions
Part 7 - Prime Mover - Fuel Data
550
Digester Gas HHV (Btu/ft3) 650
Digester Gas LHV (Btu/ft3)
300Prime Mover Rated Output (kW)
Part 7 Prime Mover Fuel Data
4,251,000 1,246
Based on Lower Heating Value (LHV) Based on Higher Heating Value (HHV)Fuel Energy (Btuh) Fuel Energy (kW)Fuel Energy (Btuh) Fuel Energy (kW)
4,329,000 1,2684,407,000
2009 - 75 percentile 10990.0% 3,597,000
100.0%Digester Gas Flow (scfm)
3,663,0003,729,0001133,795,000115
1,073111Load Description Percent of Full Load
2007 - 75 Percentile 95.3%Full Rated Capacity:
2008 - 75 Percentile 89.0%1,0931,1121,054
1,2914,485,000 1,314
Part 8 - Prime Mover - Electrical Efficiency
Ancillary Loads (kW) Net Production (kW)
1,160
25049 23750 217
50
4,680,000 1,371
286267
3,960,000
24%
94.7%
Full Rated Capacity: 100.0%26%
Gross Electrical
2008 75 Percentile 89 0%2007 - 75 Percentile 95.3%
300
23-Feb-10 120
Load Description Percent of Full Load28% 23%
20%22%
Net Electrical EfficiencyElectrical Output (kW)
Part 9 - Prime Mover - Thermal Efficiency
22150 217
284270 26%267
2009 - 75 percentile 90.0%24%
24%2008 - 75 Percentile 89.0%
21%21%20%
43 24149
Load Description27%1,000,000
Thermal EfficiencyThermal Recovery (Btuh)Jacket Water (Btuh)
23-Feb-10 94.7%
Full Rated Capacity: 100.0%Percent of Full Load
1,000,000
Part 10 - Prime Mover - Total Efficiency
22%23%22%24%27%1,000,000
852,711 852,711897,928
Full Rated Capacity: 100.0%
2009 - 75 percentile 90.0%94.7%23-Feb-10
1,000,000897,9282007 - 75 Percentile 95.3%
2008 - 75 Percentile 89.0%
876,784835,539
876,784835,539
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Total Efficiency
43%44%42%46%
23-Feb-10 94.7%2009 - 75 percentile 90.0%
Load Description Percent of Full Load
2008 - 75 Percentile 89.0%
100.0%2007 - 75 Percentile 95.3%Full Rated Capacity: 51%
2006 2007 2008 2009 AverageMaintenance Costs
Net kWH 1,590,800 1,768,600 1,666,200 1,620,500 1,647,380
Parts & Materials 15,073.68$ 35,176.00$ 38,072.00$ 40,027.00$ 31,333.49$ Siloxane Media 10 113 24$ 13 680 00$ 15 898 00$ 10 778 00$ 12 335 85$Siloxane Media 10,113.24$ 13,680.00$ 15,898.00$ 10,778.00$ 12,335.85$ Siloxane Media Disposal 3,390.84$ 7,578.00$ 7,912.00$ 6,351.00$ 6,259.76$
Subtotal Parts & Materials 28,577.76$ 56,434.00$ 61,882.00$ 57,156.00$ 49,929.09$ Cost/ kWH 0.0180$ 0.0319$ 0.0371$ 0.0353$ 0.0303$Cost/ 0.0180$ 0.0319$ 0.0371$ 0.0353$ 0.0303$
Labor 8,942.50$ 7,665.00$ 9,231.00$ 7,801.00$ 8,099.96$ Travel 16,468.47$ 15,073.00$ 19,690.00$ 13,177.00$ 15,545.03$
Subtotal Labor & Travel 25,410.97$ 22,738.00$ 28,921.00$ 20,978.00$ 23,644.98$ Cost/ kWH 0.0160$ 0.0129$ 0.0174$ 0.0129$ 0.0144$
Total O&M 53 988 73$ 79 172 00$ 90 803 00$ 78 134 00$ 73 574 07$Total O&M 53,988.73$ 79,172.00$ 90,803.00$ 78,134.00$ 73,574.07$ Cost/ kWH 0.0339$ 0.0448$ 0.0545$ 0.0482$ 0.0447$
Capital Expense to Install New Chiller Unit 58,000.00$
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p p ,$
1 Replacement Engine 3 Replacement Engines 1 Replacement EngineRepair Chiller Repair Chiller Repair Chiller Repair Chiller
Maintenance• Alliant Energy is responsible for all Maintenance
– Preventive• Change out MT Inlet Air Filters
– Every 8 Weeks• Replace Carbon Media for Siloxane RemovalReplace Carbon Media for Siloxane Removal
– Every 10 - 12 Weeks• Change Gas Compressor Oil
Annually– Annually
– Corrective• Engines• Control Modules (internal PLC)• SPV Valve (Gas Flow Control Valve)• Igniters
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Igniters
Cogeneration Project Costs• Estimated Project Cost $1,200,000• City's Cost $205 000• City s Cost $205,000• Alliant Energy’s Cost $1,000,000 (estimated)
• Focus On Energy Grants– Electrical, Approved for but Not Eligible for pp g
($45,000)– Heat Recovery, $20,000
• The City recovered its cost in just over 2-years
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2006 2007 2008 2009Benefits from CHP 2006 - 2009
2006 2007 2008 2009
Renewable Energy Credits (RECs) 924 2,076 1,619 1,571$$ Per REC $3.15 $3.15 $3.15 $0.95Revenue from RECs $2,911 $6,539 $5,100 $1,492
Revenue from Alliant Energy $23,372 $27,118 $25,730 $27,230
Therms Reco ered 60 449 66 369 65 602 60 247Therms Recovered 60,449 66,369 65,602 60,247Cost PerTherm $0.9039 $0.8347 $0.8666 $0.7352Natural Gas Savings $54,640 $55,398 $56,851 $44,294g
Wisconsin Focus On Energy Grant $20,000
19Total Revenue $100,922 $89,056 $87,681 $73,016
2006 2007 2008 2009Value of Energy Produced 2006 - 2009
2006 2007 2008 2009
Days System Down (All Day) 45 23 3 18y y ( y)
Annaul Therms 60,449 66,369 65,602 60,247A erage Dail BTUs 18 890 313 19 406 140 18 072 176 17 362 248Average Daily BTUs 18,890,313 19,406,140 18,072,176 17,362,248Value of Heat Produced $54,640 $55,398 $56,851 $44,294Cost Per Therm $0.9039 $0.8347 $0.8666 $0.7352$0.9039 $0.8347 $0.8666 $0.7352
Annual kWH 1,590,800 1,768,600 1,666,200 1,620,500A D il kWH 9 1 1 1 603 6 0Average Daily kWH 4,971 5,171 4,603 4,670Value of Electricity Prouced $98,684 $113,908 $112,169 $109,510Cost Per kWH $0 0620 $0 0644 $0 0673 $0 0676
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Cost Per kWH $0.0620 $0.0644 $0.0673 $0.0676
Total Value of Energy Produced $153,324 $169,306 $169,020 $153,804
Lessons LearnedLessons Learned
• Operation during cold weather– Heat Tape Gas Supply Lines
• Placement of Chiller Unit• Provide adequate space for gas
conditioning equipmentconditioning equipment
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High Strength Industrial Wastes• High Soluble Organic Wastes
– High Biochemical Oxygen Demand (BOD) > 25,000 mg/l– Low Total Suspended Solids (TSS) < 20,000 mg/l
E– Easy to pump– Provides increase in Methane Gas Production within minutes
• Currently using the following Food Processing WasteAdel Whey– Adel Whey
• Mother Liquor, ~120,000 mg/L BOD• Permeate, ~100,000 BOD• Permeate Rinse Water ~60 000 mg/L BODPermeate Rinse Water, 60,000 mg/L BOD
– Jeneil Biotech• Flavorings for Dairy Products, ~25,000 mg/L BOD
– Lake to Lake Cheese• Cheese Processing Brine 35,000 mg/L BOD
• Evaluating the following Food Processing Waste– Saputo Foods
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• Permeate, ~400,000 BOD, 50% Total Solids, 80% Volatile Solids
Impact of Soluble BOD on Methane Gas ProductionDecember 2006
600 000 20 000
500,000
600,000
16 000
20,000
400,000
c Fe
et)
12 000
16,000
305,218 Average300,000
hane
Gas
(Cub
ic
8,000
12,000
BO
D (P
ound
s)
200,000Met
h
4,000
8,000
0
100,000
0
,
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
Dec-06, With High Strength Waste Adell Whey (40,000 BOD) Schrieber Foods (33,000 BOD)
Total Methane Gas Produced (Used)December 2005 compared to March 2009
600 000
500,000
600,000
491,157 Average
400,000
Feet
)
300,000
ane
Gas
(Cub
ic
233,065 Average200,000M
etha
0
100,000
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
Dec-05, Without High Strength Waste March 2009, with High Strength Waste
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Summary• Using methane gas to produce energy on-site, has
reduced our dependency on outside energy sources. (electric and natural gas). ( g )
• Using methane gas to fuel the micro-turbines has reduced our green house gas emissions (Methane and Carbon Dioxide)
• Metering-in “High Strength” organic wastes into the anaerobic digesters has increased methane gas production by more than 100 percent.
• The Capstone® Micro-turbines produced 6,646 MWh of Electrical Energy and 252,667 Therms of heat since startup in February 2006.
• The 6,646 MWh of electricity reduced our carbon dioxide emissions by more than 6,000,000 pounds, the equivalent of planting 16,000 trees.
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What’s Planned for the Future
• 2010 -2011Digester Mixing Improvements– Digester Mixing Improvements
– More Capstone Micro-turbines (400 kW) • 2012 Class “A” Bio solids Project• 2012 Class A Bio-solids Project
– Low temperature sludge dryerUse excess heat for sludge stabilization– Use excess heat for sludge stabilization
– Produce a reusable soil amendment • 2013 & 2014 More Energy Projects• 2013 & 2014 More Energy Projects
– Solar Electric Energy Project• 225 000 ft2 of flat roof area
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• 225,000 ft of flat roof area• 2 megawatts of energy
Web Links to ArticlesWeb Links to Articles
• http://www werf org/AM/Template cfm?Section=Hom• http://www.werf.org/AM/Template.cfm?Section=Home&TEMPLATE=/CM/ContentDisplay.cfm&CONTENTID=10245
• http://www.jgpress.com/archives/_free/001831.html• http://www.nyserda.org/programs/Environment/07-
08%20Final%20Report pdf08%20Final%20Report.pdf• http://www.biosolids.org/news_weekly.asp?id=1928• http://www distributedenergy com/march-april-http://www.distributedenergy.com/march april
2009/sludge-is-power.aspx• http://www.tpomag.com/editorial/view/3110/Savings-
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Everywhere
Contact Info:Contact Info:Dale L. DoerrCit of Shebo gan WWTPCity of Sheboygan WWTP920-459-3464 [email protected]
Website: www.sheboyganwwtp.com29