Abstract:

The anaerobic simultaneous denitrification and methanogenesis (SMD)process has attracted considerable attention recently for the integrated removal of carbon and nitrogen.This review elucidated the mechanism of anaerobic SMD process and the involved materials and electron flow, and summarized the current research status on microbial communities and main influencing factors. Then the problems in current researches were discussed and direction for further study was proposed. More studies should be conducted to optimize the electron flow to both denitrification and methanogenesis, explore more suitable ratios of COD/NO^-_x-N and distribute the electron flow properly to produce energy-rich biogas. Additionally, the SMD process could be affected by sludge morphology, and anaerobic granular sludges or biofilms were found to be more suitable for SMD because it could relieve the inhibition of nitrogen oxides to methanogenesis.However, effects of mass transfer resistance and high suspended solids in the influent on this sludge system should be taken into consideration.