Optimal loading rates and economic analyses for anaerobic digestion of poultry waste

Four combinations of litter and carcasses from broiler chickens were examin ed utilizing a thermophilic, stirred-tank digester of demonstration size of approximately 10,000 gal. Under computed optimal loading rates, litter wit h paper bedding had the highest daily production of methane over an 8-day r etention period. The greatest methane production per lb of volatile solids was achieved over 10 days with litter and paper bedding combined with carca sses. This research found that sufficient poultry litter is generated withi n 20 mi (32 km) of Moorefield, WV, to support a commercial-sized digester o peration. However, anaerobic digestion of poultry waste cannot be financial ly supported by methane production alone. To be financially viable, anaerob ic digestion requires a disposal fee for poultry waste and/or the sale of t he digested solid effluent as an organic fertilizer to retail markets.