Microturbine OperationMicroturbine Operation

with with BiogasBiogas from a from a

Covered Dairy ManureCovered Dairy Manure

LagoonLagoon

Douglas W. WilliamsDouglas W. WilliamsBioResource and Agricultural EngineeringBioResource and Agricultural EngineeringCalifornia Polytechnic State UniversityCalifornia Polytechnic State University

San Luis Obispo, CA USASan Luis Obispo, CA USA

J.J. FrederickJ.J. FrederickStudent AssistantStudent Assistant

California Polytechnic State UniversityCalifornia Polytechnic State UniversitySan Luis Obispo, CA USASan Luis Obispo, CA USA

AcknowledgementsAcknowledgements WRBEP WRBEP (Western Regional Biomass Energy Program)(Western Regional Biomass Energy Program)

CSU-ARICSU-ARI (CA State Univ.Agricultural Research Institute)(CA State Univ.Agricultural Research Institute)

Southern California Gas CompanySouthern California Gas Company

California Polytechnic State UniversityCalifornia Polytechnic State University

Capstone MicroturbinesCapstone Microturbines

USDA-NRCSUSDA-NRCS

(Natural Resource Conservation Service)(Natural Resource Conservation Service)

Methane Production Methane Production TechnologiesTechnologies

Covered LagoonCovered Lagoon 78% Success Rate 78% Success Rate

Plug FlowPlug Flow 37% Success Rate 37% Success Rate

Complete MixComplete Mix 30% Success 30% Success RateRate

Covered Lagoon Digester at Covered Lagoon Digester at 9000-head Swine Farm 9000-head Swine Farm

Lagoon Digester and Biogas Lagoon Digester and Biogas HandlingHandling

Successful Biogas-fueled 60 KW Successful Biogas-fueled 60 KW Engine-GeneratorEngine-Generator

FARM DESCRIPTIONFARM DESCRIPTION Free Stall DairyFree Stall Dairy

~ 300 Cows, Heifers, Calves~ 300 Cows, Heifers, CalvesEquivalent /250 AU’s (Animal Units)Equivalent /250 AU’s (Animal Units)

Flushed Dairy Manure RemovalFlushed Dairy Manure Removal250 to 400 cubic meters/day250 to 400 cubic meters/day.3 to .4 % Total Solids.3 to .4 % Total Solids

3000 to 4000 mg/l COD3000 to 4000 mg/l COD

Electrical UsageElectrical Usage234,000 KWhrs/year234,000 KWhrs/year$21,000 per year$21,000 per year

Cal Poly Dairy Parlor and Cow Cal Poly Dairy Parlor and Cow LaneLane

Figure 1. Covered Lagoon Figure 1. Covered Lagoon SchematicSchematic

Sump and pump

Irrigation pump

Recycle flush water pump

Slurry Inlet

MilkingParlor

SolidsSeparator

ManureSolids

30 kW Micro-Turbine electric GeneratorSystem

Below-ground Biogas Line

Overflow to storage

 

Existing Storage Lagoon, 19,000 cubic meters capacity

 

New Covered Lagoon, 14,000 cubic meters liquid capacity

FLUSHED MANURE WASH ALLEY

 

                     

  

 

Sump and

Transfer Pump

Measuring Influent Flow into Measuring Influent Flow into LagoonLagoon

Lagoon CoverLagoon Cover

Lagoon Covers and Biogas Pipe Lagoon Covers and Biogas Pipe ConnectorConnector

Lagoon Cover and Biogas PipeLagoon Cover and Biogas Pipe

Biogas Pipe InstallationBiogas Pipe Installation

Biogas pipe with Condensate Biogas pipe with Condensate TrapTrap

Biogas Piping Condensate Biogas Piping Condensate Removal BoxRemoval Box

Biogas Handling SystemBiogas Handling System

Biogas Equipment and Lagoon Biogas Equipment and Lagoon CoverCover

Compressor, Microturbine and Compressor, Microturbine and Heat ExchangerHeat Exchanger

TABLE 1TABLE 1

MAJOR EQUIPMENT ITEMSMAJOR EQUIPMENT ITEMS Digester Cover and InstallationDigester Cover and Installation 90,000 90,000

Gas HandlingGas Handling 5,000 5,000

Micro-Turbine Compressor, Heat ExchangeMicro-Turbine Compressor, Heat Exchange 50,000 50,000

Electric Generator Building and UtilityElectric Generator Building and Utility 5,000 5,000

Utility Tie-inUtility Tie-in 5,000 5,000

Equipment SubtotalEquipment Subtotal 155,000155,000

CONSTRUCTIONCONSTRUCTIONEngineeringEngineering 25,000 25,000

Construction SubtotalConstruction Subtotal 25,00025,000

TOTAL $TOTAL $180,000180,000

PROJECT STATUS

Cover Installed90% of area covered

Biogas Production200 to 300 cu meters/day

88% Methane, 12% CO2 Biogas tested in 10 KW Engine-

Generator Set 75% COD Reduction

Microturbine and Covered Microturbine and Covered LagoonLagoon

10 KW Engine-Gen Set10 KW Engine-Gen Set

Biogas Measurement by Cal Poly Biogas Measurement by Cal Poly StudentsStudents

10 KW Engine-Generator Test on 10 KW Engine-Generator Test on BiogasBiogas

Engine Generator at Full 10 KWEngine Generator at Full 10 KW

Covered Lagoon Effluent PipeCovered Lagoon Effluent Pipe

CONCLUSIONS 10 KW Engine-Generator Test

Input: 11 cubic meters/hrOutput: 10 KW Efficiency:10%

30 KW Microturbine Specification:Input: 13 cubic meters/hrOutput: 28 KWEfficiency: 27%

Effluent Characteristics:1000 to 1500 mg/l COD90 mg/l Ammonia

BENEFITS OF ANAEROBIC DIGESTION

Odor control

Effective Manure and NutrientManagement

Electrical Returns 170,000 KWhrs/year

$15,500/year75% of Demand