Anaerobic Digestion Characteristics for Sewage Sludge and Organic Wastes by Batch Experiments

Abstract

 Co-digestion of sewage sludge and other organic wastes is a promising technology. Anaerobic digestion characteristics for organic wastes, including sewage sludge, food factory waste, kitchen garbage, livestock waste, and vegetable waste, were analyzed by batch experiments using digested sludge adapted to these wastes in advance. The COD base methane conversion ratios in mesophilic and thermophilic conditions were similar and around 0.6 (-) or over. The reaction rates for wastes with higher methane conversion ratios were faster. The effects of substrate compositions on digested sludge quality such as ammonia, phosphate and potassium concentrations were quantitatively evaluated. These results can be used to evaluate co-digestion performances in different areas.