EVALUATING THE IMPACT OF DIFFERENT CARBON SOURCE AND COD/NO3-N RATIO ON COUPLING PARTIAL DENITRIFICATION AND ANAMMOX

Abstract

As the nitrogen discharge limit gets more stringent, ammonium and nitrate residual in the effluent of mainstream deammonification process are becoming an issue that need to be addressed. Thus, developing a post-deammonification polishing process is necessary to promote the implementation of mainstream deammonification. In this study, a final polishing process coupling anammox with partial denitrification is proposed to simultaneously remove ammonium and nitrate, and the long-term (120 days) impact of carbon type and COD/N ratio on promoting partial denitrification was evaluated. Results suggested that acetate and glycerol displayed a good potential for promoting partial denitrification. However, methanol showed challenges of establishing efficient partial denitrification in long-term operation. The key factor for a successful concurrent operation of anammox and partial denitrification lies on controlling the balance between denitrifier rate and AnAOB rate to simultaneously remove residual ammonium and nitrate.