初沉池优化运行对改良型A^(2)/O工艺脱氮除磷的影响  

Effect of optimizing operation of primary sedimentation tank on nitrogen and phosphorus removal of modified A^(2)/O process

作　　者：李航 董立春[1] 方建飞 丁力 吕利平[3] LI Hang;DONG Lichun;FANG Jianfei;DING Li;LÜLiping(School of Chemistry and Chemical Engineering, Chongqing University;Chongqing Three Gorges Water Co. , Ltd.;School of Chemistry and Chemical Engineering, Yangtze Normal University)

机构地区：[1]重庆大学化学化工学院 [2]重庆市三峡水务有限责任公司 [3]长江师范学院化学化工学院

出　　处：《环境工程技术学报》2021年第6期1189-1195,共7页Journal of Environmental Engineering Technology

基　　金：重庆市教委科学技术研究计划青年项目(KJQN201901429)。

摘　　要：采用改良型A^(2)/O工艺处理城市污水,设置6种工况,即原水进入初沉池与超越初沉池直接进入生物池流量分配比分别为10∶0、8∶2、6∶4、4∶6、2∶8、0∶10,在具体工程实例中考察初沉池优化运行对脱氮除磷效果的影响。结果表明:初沉池的优化运行对出水总氮浓度和生物除磷率具有显著影响,而对出水氨氮浓度影响较小。工艺中存在反硝化除磷现象,且反硝化除磷率与原水超越初沉池直接进入生物池流量分配比呈正相关。基于6种工况,较为优化的原水进入初沉池与超越初沉池直接进入生物池流量分配比为6∶4。该工况后期出水总氮平均浓度为8.79 mg/L,较原工况降低了33.9%,氨氮浓度低于0.5 mg/L,好氧区总磷平均浓度为0.34 mg/L,满足GB 18918—2002《城镇污水处理厂污染物排放标准》一级A排放标准;电耗为0.337 kW·h/m^(3),仅比原工况上涨了5.31%,涨幅较小。相比于原工况,虽然电耗出现了轻微上涨,但出水水质可控性得到了进一步强化,且显著优于一级A排放标准。The modified A^(2)/O process was used to treat urban sewage,and the effect of optimized operation of primary sedimentation tank(PST)on nitrogen and phosphorus removal were investigated in the specific engineering example.Six different operation conditions were adopted in the test,namely,the flow distribution ratio of raw water entering PST to that directly entering the biological tank stepping over PST were 10∶0,8∶2,6∶4,4∶6,2∶8 and 0∶10,respectively.The results showed that the optimized operation of PST had significant influence on the concentration of total nitrogen in the effluent and the efficiency of biological phosphorus removal,but had little influence on the ammonia nitrogen concentration.The phenomenon of denitrifying phosphorus removal existed in the experimental process,and the denitrifying phosphorus removal rate was positively related to the flow distribution ratio of raw water stepping over PGT directly entering the biological tank.Among the six different conditions,the more optimal flow distribution ratio of raw water entering PST to that directly entering the biological tank stepping over PST was 6:4.In the later stage of this condition,the average concentration of total nitrogen in the effluent was 8.79 mg/L,which was 33.9%lower than the original condition;the concentration of ammonia nitrogen was lower than 0.50 mg/L,and the average concentration of total phosphorus in aerobic area was 0.34 mg/L,which met the first level A standard of Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant(GB 18918-2002);the power consumption was 0.337 kW·h/m^(3),which was only 5.31%higher than the original operation condition,with a small increase.Compared with the original condition,although the power consumption slightly increased,the controllability of the effluent water quality was further strengthened,and it was significantly better than the discharge standard of the first level A.

关 键 词：初沉池 流量分配比 改良型A^(2)/O工艺 脱氮除磷 反硝化除磷 电耗 

分 类 号：X703[环境科学与工程—环境工程]