Performance of simultaneous nitrification-denitrification and denitrifying phosphorus and manganese removal by driving a single-stage moving bed biofilm reactor based on manganese redox cycling.

Simultaneous removal of NH-N, NO-N, COD, and P by manganese redox cycling in nutrient wastewater was established with a single-stage moving bed biofilm reactor (MBBR) under low C/N ratio. When sodium succinate replaced the conventional denitrifying carbon source, removal efficiencies of TN, NO-N, NH-N, TP, and Mn were 65.13 %, 79.63 %, 92.79 %, 51.57 %, and 68.10 %, respectively. Based on modified Stover-Kincannon model, 11.03 and 10.05 mg TN·L·h of U values were obtained with sodium acetate and sodium succinate as substrates. Extracellular polymeric substances were used to evaluate the characteristics of biofilm, and microbial community of biofilm was identified. Transformation processes of NO-N, NH-N, Mn, and P were investigated, suggesting that the main functional groups (e.g., CO, Mn-O, and CN bonds) participated in N, P, and Mn removal, and MnO was the main component of biogenic manganese oxides. This study provides a new strategy for nutrients removal by Mn driven MBBR.