Microturbine Operation with Biogas from a Covered Dairy Manure Lagoon

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Microturbine Operation with Biogas from a
Covered Dairy Manure Lagoon
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Douglas W. WilliamsBioResource and Agricultural
EngineeringCalifornia Polytechnic State
UniversitySan Luis Obispo, CA USAJ.J.
FrederickStudent AssistantCalifornia
Polytechnic State UniversitySan Luis Obispo, CA
USA
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Acknowledgements

• ? WRBEP
• (Western Regional Biomass Energy
  Program)
• ? CSU-ARI
• (CA State Univ.Agricultural Research
  Institute)
• ? Southern California Gas Company
• ? California Polytechnic State University
• ? Capstone Microturbines
• ? USDA-NRCS
• (Natural Resource Conservation Service)
  

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Methane Production Technologies

• ? Covered Lagoon 78 Success Rate
• ? Plug Flow 37 Success Rate
• ? Complete Mix 30 Success Rate

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Covered Lagoon Digester at 9000-head Swine Farm
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Lagoon Digester and Biogas Handling
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Successful Biogas-fueled 60 KW Engine-Generator
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FARM DESCRIPTION? Free Stall Dairy
300 Cows, Heifers, Calves Equivalent /250
AUs (Animal Units) ? Flushed Dairy Manure
Removal 250 to 400 cubic meters/day .3 to .4
Total Solids 3000 to 4000 mg/l
COD ? Electrical Usage 234,000
KWhrs/year 21,000 per year
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Cal Poly Dairy Parlor and Cow Lane
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Figure 1. Covered Lagoon Schematic
 
 
Milking Parlor
                                             
FLUSHED MANURE WASH ALLEY
Recycle flush water pump
Irrigation pump
Overflow to storage
Sump and pump
Below-ground Biogas Line
  Existing Storage Lagoon, 19,000 cubic meters
capacity
  New Covered Lagoon, 14,000 cubic meters liquid
capacity
30 kW Micro-Turbine electric Generator System
Solids Separator
Manure Solids
Transfer Pump
Slurry Inlet
Sump and
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Measuring Influent Flow into Lagoon
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Lagoon Cover
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Lagoon Covers and Biogas Pipe Connector
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Lagoon Cover and Biogas Pipe
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Biogas Pipe Installation
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Biogas pipe with Condensate Trap
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Biogas Piping Condensate Removal Box
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Biogas Handling System
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Biogas Equipment and Lagoon Cover
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Compressor, Microturbine and Heat Exchanger
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TABLE 1

• MAJOR EQUIPMENT ITEMS
• Digester Cover and Installation 90,000
• Gas Handling 5,000
• Micro-Turbine Compressor, Heat Exchange
  50,000
• Electric Generator Building and Utility
  5,000
• Utility Tie-in 5,000
• Equipment Subtotal 155,000
• CONSTRUCTION
• Engineering 25,000
• Construction Subtotal 25,000
• TOTAL 180,000

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• PROJECT STATUS
• ? Cover Installed 90 of area
  covered ? Biogas Production 200 to 300 cu
  meters/day 88 Methane, 12 CO2
• ? Biogas tested in 10 KW Engine- Generator Set
• ? 75 COD Reduction

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Microturbine and Covered Lagoon
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10 KW Engine-Gen Set
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Biogas Measurement by Cal Poly Students
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10 KW Engine-Generator Test on Biogas
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Engine Generator at Full 10 KW
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Covered Lagoon Effluent Pipe
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• CONCLUSIONS
• ? 10 KW Engine-Generator Test
• Input 11 cubic meters/hr
• Output 10 KW
• Efficiency10 ? 30 KW Microturbine
  Specification
• Input 13 cubic meters/hr
• Output 28 KW
• Efficiency 27
• Effluent Characteristics
• 1000 to 1500 mg/l COD
• 90 mg/l Ammonia

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BENEFITS OF ANAEROBIC
DIGESTION? Odor control ? Effective Manure
and Nutrient Management? Electrical Returns
170,000 KWhrs/year 15,500/year 75 of
Demand