多级A/O深度处理城镇低生化性污水脱氮除磷探究

Study on the Nitrogen and Phosphorus Removal of Municipal Low-Biochemical Sewage by Multi-Stage A/O Process

为了探究多级A/O工艺对城镇低C/N废水的脱氮除磷效率的影响,构建新型多级A/O工艺反应器及传统序批式反应器(SBR)。结果表明,稳定运行期多级A/O工艺TN和TP去除率高达79.6%±5.2%和81.3%±3.5%。当进水pH为5和7时,多级A/O工艺对COD的去除高于SBR;而当进水pH为9时,两工艺中COD去除率相似。不同进水pH条件下,多级A/O工艺对TN及TP的去除率高于SBR。进水pH为7时,多级A/O中污泥胞外聚合物的质量分数为(175.6±9.0)mg/g,蛋白质与多糖的含量比为1.32,均低于其他进水pH;pH为7时,多级A/O工艺中与脱氮除磷相关关键酶的活性均高于其他pH。进水pH为时Proteobacteria、Bacteroidetes和Chloroflexi的相对丰度显著高于其他组别。

In order to explore the effect of multi-stage A/O process on the nitrogen and phosphorus removal efficiency of low-C/N wastewater in urban,the new multi-stage A/O process reactor and traditional sequential batch reactor(SBR)were constructed.The results showed that the tTN and TP removal efficiency by the multi-stage A/O process in the stable operation period were as high as 79.6%±5.2%and 81.3%±3.5%,respectively.When the pH of the feed water was 5 and 7,the removal of COD by the multi-stage A/O process was higher than that of SBR,and when the pH of the feed water was 9,the removal efficiency of COD in the two processes was similar.The removal efficiencies of TN and TP by multi-stage A/O process were higher than those of the SBR under different pH conditions.When the feed water pH was 7,the content of extracellular polymer in sludge of multistage A/O was(175.6±9.0)mg/g,and the ratio of protein to polysaccharide was 1.32,which were lower than other feed water pH.When pH was 7,the activities of key enzymes related to nitrogen and phosphorus removal in the multi-stage A/O process were higher than other pH.The relative abundances of Proteobacteria,Bacteroidetes,and Chloroflexi were significantly higher than those of other groups.