Abstract:The characteristics of biological nitrogen (N) and phosphorus (P) removal under different nitrate recycling ratios were investigated in a Anaerobic/Anoxic/Oxic (A2O)-Biological Contact Oxidation (BCO) system when treating low C/N in municipal wastewater. The results indicated that the removal of N and P was achieved simultaneously, and denitrifying phosphorus removal (DPR) process was realized with the total hydraulic retention time (HRT) of A2O at 8h, sludge reflux ratio of 100%, and nitrate recycling ratios set as 100%, 200%, 300% and 400% respectively. The effluent concentration of COD was less than 50mg/L. The removal efficiencies of total nitrogen (TN) were 48.8%, 66.5%, 75.6% and 62.5%, and the removal efficiencies of total phosphorus (TP) were 86.0%, 90.3%, 91.0% and 95.0% under various nitrate recycling ratios. When the nitrate recycling ratio was set at 300%, average concentration of TN and TP in effluent were 14.96mg/L and 0.49mg/L. The amount of denitrifying phosphorus removed was increased slightly as the nitrate recycling ratio improved. When the nitrate recycling ratio was set at 400%, the amount of P removed by DPR accounted for 98% of the total phosphorus removed.
王聪, 王淑莹, 张淼, 汪传新, 薛晓飞, 庞洪涛, 彭永臻. 硝化液回流比对A2/O-BCO工艺反硝化除磷特性的影响[J]. 中国环境科学, 2014, 34(11): 2844-2850.
WANG Cong, WANG Shu-Ying, ZHANG Miao, WANG Chuan-Xin, XUE Xiao-Fei, PANG Hong-Tao, PENG Yong-Zhen. Effect of nitrate recycling ratio on denitrifying phosphorus removal characteristics in A2O-BCO process. CHINA ENVIRONMENTAL SCIENCECE, 2014, 34(11): 2844-2850.