前置A2NSBR系统硝化和反硝化除磷的特性

以处理实际低C/N生活污水的前置A₂NSBR系统为研究对象，考察系统内生物膜的硝化特性和活性污泥的反硝化除磷特性.试验研究了有机物和NO₂^--N浓度对生物膜硝化性能的影响，以及不同电子受体浓度对反硝化吸磷速率的影响.结果测得硝化速率为11.3mgNH₄⁺-N/（L·h），在填充率40%的条件下容积负荷为0.27kgNH₄⁺-N/（m³·d），有机物的存在会对硝化有抑制，但是系统表现出了良好的抗有机负荷冲击能力，硝化速率为9.72mg NH₄⁺-N/（L·h）.NO₂^--N处理对AOB活性几乎无影响，对NOB活性抑制作用明显，当NO₂^--N浓度为400mg/L时，NOB活性仅为1.63%，几乎接近完全被抑制.根据本次不同电子受体条件下除磷批次试验的结果，好氧吸磷速率为17.62mg P/（g VSS·h），以NO₃^--N为电子受体的缺氧吸磷速率是12.94mg P/（g VSS·h），从而可知缺氧聚磷菌占总聚磷菌的比例大约是73.4%，其中在NO₂^--N浓度为30mg/L出现吸磷抑制，当NO₂^--N和NO₃^--N共存时，NO₂^--N在初始浓度为15mg/L便出现吸磷抑制.

Nitrification and denitrifying phosphorus removal performance in the pre-A2 NSBR system

Biofilm nitrification and activated sludge denitrifying phosphorus removal performance were investigated in the pre-A₂ NSBR system, which treated real low carbon to nitrogen (C/N) ratio domestic sewage. The effect of organic substance and NO₂^--N concentration on the biofilm nitrification performance, and different electronic acceptors on the denitrifying phosphorus uptake rate were studied. Results indicated that nitrification rate was 11.3 mgNH₄⁺-N/(L·h), the ammonia volume loading was 0.27 kgNH₄⁺-N/(m³·d) under the filling rate of 40%, the nitrification performance was inhibited by organic substance, but the system showed a good nitrification rate of 9.72 mg NH₄⁺-N/(L·h) when organics presented. NO₂^--N treatment exhibited little effect on the AOB activity but obvious effect on the NOB activity, the NOB activity was almost completely inhibited (only 1.63%) when NO₂^--N concentration was 400mg/L. According to the phosphorus uptake rate experiment under different electronic acceptors, the phosphorus uptake rate under oxygen and NO₃^--N was 17.62mg P/(g VSS·h) and 12.94mg P/(g VSS·h), respectively, anoxic phosphate accumulating organisms (PAOs) occupied 73.4% of the total PAOs, phosphorus uptake performance was inhibited when the NO₂^--N concentration was 30mg/L, and phosphorus uptake performance was inhibited when the NO₂^--N concentration was 15mg/L under the condition of NO₂^--N and NO₃^--N coexisted.