Research and application of enhanced methanogenesis under anaerobic digestion acid accumulation condition
In actual operation,anaerobic digestion system is susceptible to various conditions,leading to accumulation of volatile fatty acids,which further inhibits methanogenesis and finally cause anaerobic digestion system collapses.According to the analysis results,pH value,types and concentrations of volatile fatty acids,are determined to be the reasons for acid accumulation inhibiting methanogensis.The effects of biological enhance-ment technology by adding acidophilic methanogens and propionate methanogens,and exogenous strengthening technology by adding magnetite,nano zero-valent iron,activated carbon,biochar and grapheme,were reviewed.It was indicated that,future research could be carried out from aspects of strengthening mechanism exploration on acid accumulation inhibiting methanogenesis,using mathematic model to warn,adjust and control acid accumula-tion process,and so on.