采用倒置A2/O工艺处理垃圾渗滤液与城市污水的混合污水。模型试验结果表明,水力停留时间是影响混合污水氮和有机物去除的控制因素;水温为23~30℃、泥龄为20d时,最优运行参数为:水力停留时间9h、DO 2mg/L、外回流比80%、内回流比200%,此时COD、NH3-N和TN去除率分别为76.4%~78.2%、95.7%~97.8%和58.9%~61.2%,出水浓度均可稳定达到《城镇污水处理厂污染物排放标准》(GB 18918—2002)一级A标准。当水温为13~27℃,其他工艺条件与模型试验相同时,生产性试验得出,COD、NH3-N和TN去除率分别为74.7%~87.8%、87.2%~98.6%、51.8%~67.4%;出水COD和NH3-N均达到GB18918—2002一级A标准,出水TN达到GB 18918—2002一级B标准。与上一年同期运行效果比较,NH3-N和TN平均去除率分别提高了9.4、9.9百分点,有机物去除没有改善。
The inversion A2 /O process was applied for simultaneous treatment of landfill leachate and urban sewage,and orthogonal test were conducted to find out the optimization operating condition.Model experiment showed that the hydraulic retention time(HRT) was the key factor of nitrogen and organic removal.When water temperature ranged 23-30 ℃,optimal operation parameters were HRT 9 h,DO 2 mg/L,reflux rate 80%,and inner cycle mixed liquid rate 200%,under these optimize conditions,COD,NH3-N and TN removal rate in model were 76.4%-78.2%,95.7%-97.8% and 58.9%-61.2% respectively.The effluent was steadily reached to standard A of "Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant"(GB 18918-2002).When water temperature ranged 13-27 ℃ and applying the obtained operating parameter,COD,NH3-N and TN removal rate in productive experimental were 74.7%-87.8%,87.2%-98.6%,and 51.8%-67.4% respectively.Effluent COD and NH3-N was qualified to level A of GB 18918-2002,and effluent TN was satisfy level B of GB 18918-2002.Compared with the running effect of same period at usual,NH3-N and TN average removal rate was increase by 9.4% and 9.9% respectively.