混合液回流比对多点进水新型A/O/A/A/O泥膜耦合工艺脱氮除磷的影响

针对中国南方城镇低碳氮比(低C/N)生活污水的脱氮除磷问题,开发并设计了新型多点进水A1/O2/A3/A4/O5泥膜耦合工艺及中试装置.在进水点1和进水点2的进水流量比为4:6的条件下,通过改变混合液回流比,研究了其对系统中有机物、氮、磷的去除影响及氮素的转化规律.结果表明:当平均进水低C/N比为2.09,混合液回流比...

Influence of mixed liquid reflux ratio on a new multiple-inflow A/O/A/A/O sludge-biofilm coupling process for denitrification and phosphorus removal

A new multiple-inflow A1/O2/A3/A4/O5 sludge-biofilm coupling process and its pilot facility were developed and designed for the denitrification and phosphorus removal from domestic sewage with low C/N ratio in the towns of South China. At the inlet flow ratio of 4: 6 between inlet point 1 and inlet point 2, the influence of the mixed liquid reflux ratio on the removal of organic matter, nitrogen and phosphorus in the system and the rule of nitrogen transformation were studied. The results showed that when the average C/N ratio was 2.09 and the mixed refluent ratio was 300%, the average values of COD, ${\rm{NH}}_4^ + $-N, TN and TP in the effluent were 23.45, 0.80, 12.41 and 0.36 mg·L−1, respectively, and the corresponding average removal rates were 86.88%, 98.25%, 77.68% and 90.31%, respectively. Compared with multi-stage inflow A/O/A/A/O sludge-biofilm coupling process, the TN removal rate of the system increased from 68.28% to 77.68% and the TP removal rate increased from 75.22% to 90.31% after the mixed liquid reflux increased. This system has significant advantages in denitrification and phosphorus removal from low carbon nitrogen ratio sewage, and solves the problem that the phosphorus effluent is difficult to be below 0.5 mg/L in the biological treatment of low carbon and nitrogen ratio sewage.