中文摘要：

采用广州市D污水厂倒置A^2／O工艺的模拟反应器，通过单因素试验和正交试验发现，HRT是影响脱氮的最关键因素，为实现高效脱氮，水力停留时间至少应维持8h；在水温28-35℃、粪便污水与城市污水混合比1：300时，最优运行参数如下：泥龄20d、水力停留时间8h、DO质量浓度2．0mg／L、污泥回流比80％、混合液回流比150％。在此工况下运行，NH3-N去除率为97．0％～99．4％，TN去除率为61．4％～68．7％，且出水浓度均可满足《城镇污水处理厂污染物排放标准》一级A标准。

英文摘要：

The problem of denitrification in the inverted A^2/O process of a sewage treatment plant in Guangzhou is studied, which arose in treating the mixed wastewater of nightsoil sewage and municipal wastewater. The results of the single factor experiment and orthogonal tests show that HRT was the key factor for nitrogen removal efficiency through. In order to get a higher nitrogen removal efficiency, HRT should be more than 8 h. Under the conditions that water temperature was 28-35℃, and the mixing ratio of nightsoil wastewater to municipal wastewater was 1 ： 300, the optimum operation parameters were as follows.SRT 20 d ,HRT 8 h,DO 2.0 mg/L,R 80% and r 150%. Under such conditions, removal rates of ammonia and nitrogen were 97.0%-99.4% and 61.4-68. 7%, respectively, and the effluent concentration reaches the A level standard according to the Discharge Standard of Pollutants for Municipal Wasterwater Treatment Plant.