投加悬浮填料强化A^2/O工艺脱氮除磷中试

Enhancing Nitrogen and Phosphorus Removal in A^2/O Process by Adding Suspended Carrier

针对国内污水处理厂在升级改造中面临用地受限、出水水质难以稳定达标等问题,拟采用移动床生物膜工艺加以解决。中试研究表明,泥膜复合系统运行效果良好,抗冲击负荷能力强,可同时强化脱氮除磷,出水COD、TN、NH_4^+-N浓度均能稳定达到一级A标准,平均值分别为27.96、10.72、1.21 mg/L,均优于活性污泥系统,且进水负荷提高了25%。当污泥浓度为2.8~3.2g/L、DO控制在1.2~1.6 mg/L、按C/N值为3~4投加碳源时,对TN的去除效果最佳,去除率达到82%以上。好氧区悬浮填料经过72 d生物膜成熟,最终表面负荷达到了1.39 g N/(m^2·d);缺氧区悬浮填料至120 d时表面负荷达到1.28 g N/(m^2·d)。将移动床生物膜工艺用于A^2/O的升级改造,可大幅提高容积负荷,且出水水质能够稳定达标。

To address the problems of limited land area and poor effluent quality in the upgrading of domestic WWTPs, MBBR was proposed to solve the problems. The results of pilot study showed that the integrated sludge-biofilm system operated well, with strong resistance to impact load, and the removal of nitrogen and phosphorus could be enhanced simultaneously. The effluent concentrations of COD, TN and NH4^＋ - N were 27.96 mg/L, 10.72 mg/L and 1.21 mg/L, respectively, which could stably reach to the first level A criteria, and were superior to those of activated sludge system, with an increase of influent load by 25%. When the sludge concentration was 2.8 to 3.2 g/L, DO was 1.2 to 1.6 mg/L and carbon source was added with C/N of 3 to 4, the removal efficiency of TN was more than 82%. The surface load of the suspended carrier in the aerobic zone was 1.39 gN/（m^2·d） on the 72^nd day. The surface load of the suspended carrier in the anoxic zone was 1.28 gN/（m^2·d） on the 120th day. Applying MBBR to the upgrading of A^2/O process can significantly increase the volume load, and the effluent quality can meet the discharge standard.