A/A/O-MBR组合工艺强化去除氨氮及其硝化速率

将PVDF帘式中空纤维膜组件与A／A／O工艺结合，构建“A／A／O—MBR”强化生物脱氮的中试系统，用于处理太湖流域城镇污水。针对组合工艺的脱氮效果，以组合工艺MBR池内活性污泥的硝化速率为研究对象，分析了溶解氧（DO）浓度、进水氨氮浓度和温度对硝化速率的影响。结果表明，组合工艺在夏季和冬季的氨氮平均去除率分别稳定为96．56％和96．68％；低温（T〈15℃）条件下，进水氨氮浓度对硝化速率影响不大；温度升高硝化速率加快，温度为30．5℃时组合工艺的硝化速率为11．8℃时的2．6倍；与常规工艺相比，组合工艺的硝化速率是氧化沟工艺的2．3倍。组合工艺两级硝化空间形成的较长水力停留时间和MBR内膜的截留作用补偿了低温对硝化速率的影响。

Enhanced Ammonia Removal and Nitrification Rate of A/A/O MBR Combined Process

By combining the membrane bioreactor of the PVDF hollow fiber membrane with the A/A/O process, a pilot test system of A/A/O-membrane process （A/A/O-MBR） was constructed and employed in treating municipal wastewater in Taihu Lake Basin. According to the nitrogen removal of combined process, the nitrification rate of activated sludge in MBR was studied. The effect of dissolved oxygen concentration, influent ammonia nitrogen concentration and temperature on nitrification rate was analyzed. It is found that the average removal rates of ammonia nitrogen of combined process are 96.56% and 96. 68% in summer and winter, respectively. Influent ammonia concentration has little effect on nitrification rate at low temperature of less than 15.0℃. Higher temperatures would speed up the nitrification rate and the nitrification rate of combined process at 30.5 ℃ was 2.6 times than that at 11.8 ℃. Compared with the conventional process, nitrification rate of combined process was 2.3 times than that in oxidation ditch. The enhanced nitrification of long hydraulic retention time formed by two nitrification phase and the role of membrane filtration in MBR offset the inhibitory effects of low temperature on nitrification rate.