Methanogenic diversity changes in full-scale anaerobic digesters by co-digestion of food waste and sewage sludge

© 2022, Springer Japan KK, part of Springer Nature.This study aims to investigate the methanogenic community of anaerobic mono-digestion of sewage sludge (SL-digester) and co-digestion of sewage sludge with food waste (co-digester). The volatile solids, chemical oxygen demands, organic fractions, and ions in influent wastewater of digester can affect both SL-only digester and co-digester. An increase of [NH4+] in the anaerobic digester affected organic removal efficiency and microbial diversity. Methanobrevibacter smithii (33.8 ± 14.7%), Methanoculleus receptaculi (12.3 ± 5.3%), Methanolinea mesophila (9.5 ± 4.1%), and Methanospirillum hungatei (5.5 ± 9.2%) were dominant in every digester. These methanogens had a significant correlation with physicochemical properties (VFA and NH4+) or methanogens depending on their microbial metabolic pathway such as propionate degradation or ammonia resistance. This research would be used as a guideline to solve the complexity of full-scale plants’ operation and reveal the ‘black-box’ of anaerobic digestion.11Nothe