Anaerobic Digestion Technology

History of GVSU/MAREC Digester Plant Project

MPSC Michigan Energy Efficiency Grant for $1 millionAwarded to GVSU/MAREC August 2005

Dr. Imad MahawiliExecutive Director Muskegon SmartZone/MAREC

Sarah LineberryBiomass Plant Project Manager

GVSU/MAREC Digester Plant Team

den Dulk Dairy Farms, LLC: Digester Farm Site

Reynolds, Inc: General Contractor

Entec Biogas, gmbh: Digester Plant Technology

Photo Courtesy GVSU/MAREC 2007

Photo Courtesy GVSU/MAREC 2007

Photo Courtesy GVSU/MAREC 2007

Photo Courtesy GVSU/MAREC 2007

By-Products from Ravenna Digester Plant

Biogas5.1. 60 cfm biogas: 60% CH4, <200 ppm H2S6.2. Total Power Generated: 222 kW7.3. Parasitic Load of Plant: 45 kW8.4. Remaining Power Delivered to Farm: 177 kW

Digestate11.1. Solids Fraction: used as bedding in barns12.- no E. coli13.- no Streptococcus14.- no increase in mastitis counts15.2. Liquids Fraction: used as fertilizer for land application16.- overall less volume, therefore reduced transportation to fields17.- farm has moved to injection, therefore significantly reduced odor plume

Operation & Maintenance of Ravenna Digester Plant

Daily Monitoring1. Verify reception tank has proper liquid level and desired dry matter concentration of manure2. Verify no alarms have taken place that need to be addressed

Weekly Monitoring1. Verify H2S scrubber performance – measure H2S concentration2. Spray clean liquid/solid separator compressor rollers

Monthly, Quarterly, Annual Monitoring1. Pumps, motors, gear boxes, VFD’s3. Clean out sumps – to remove sludge from the bottom of the tank

Entec Biogas Anaerobic Digestion (AD) Technology

Waste StreamsLivestock Manures – dairy, pig, poultryFood and restaurant wasteOrganics separated from Solid WasteSlaughterhouse wasteFood processing wasteDistillery mashMunicipal sludgeYard waste

Market Targets

3.1. Agricultural industry1. Generate energy from waste2. Reduce pathogens, BOD/COD 3. Generate bedding or compost from fibers

4.2. Food processing industry1. Generate energy from waste2. Reduce BOD/COD3. Generate fertilizer

5.3. Solid waste industry1. Generate energy from waste2. Reduce quantity delivered to landfills3. Generate fertilizer

Biomass Revenue Streams

Biomass

Carbon Credits

Digestate - Fertilizer - Bedding - Compost

Biogas - Electric energy - Thermal energy

Benefits Compared to Fossil Fuels

1. Carbon neutral

2. Renewable AND sustainable

2. Not a water consumer or pollutant

3. Not a significant air pollutant (air permit exemption)

4. All by-products can be fully utilized