Process Performance and Functional Microbial Community in the Anaerobic Digestion of Chicken Manure: A Review

Anaerobic digestion is one of the most widely used treatment methods for animal manure. Chicken manure has high methane production potential and is thus a suitable substrate for biogas plants. However, high nitrogen content inhibits the metabolism of anaerobic microorganisms and thus hinders methane production from chicken manure. Enhancing the performance of anaerobic digestion for chicken manure is indeed a long-standing challenge. This review presents new insights into maintaining methanogens' activities, the decomposition of acetate, and the dynamics of methanogenic pathways under high ammonia stress. This review also analyzed the possible strategies for alleviating ammonia inhibition effects, including supplementing trace elements, co-digestion with nitrogen-less materials, in-situ ammonia removal, and long adaptation of anaerobic consortia to ammonia stress. The insights obtained in this paper may provide helpful information for a better understanding of anaerobic digestion technology for chicken manure and other nitrogen-rich waste and wastewater.