高悬浮物进水对中试规模微压内循环生物反应器处理效果的影响

Influence of high suspended solids influent on the treatment effect of the pilot-scale micro-pressure swirl reactor

采用中试规模微压内循环生物反应器(MPSR)处理某北方城市新区污水处理厂沉砂池出水,考察了高悬浮物进水条件下反应器污染物处理效果及污染物的去除特性,利用高通量测序对微生物群落结构进行分析。MPSR经450 d的运行结果表明,受春季冰雪融化和夏季降雨影响,反应器进水中SS质量浓度平均值在1—5月提高至约800 mg·L^(-1),在5—8月达到约2 700 mg·L^(-1),运用SPSS对进水SS与COD进行相关性分析,二者为正相关,皮尔逊相关系数为0.682。高悬浮物进水使得系统内MLSS质量浓度增加至12 000 mg·L^(-1),而MLVSS质量浓度基本保持在3 000~5 000 mg·L^(-1), SVI下降至50 mL·g^(-1)。在不同进水负荷条件下,MPSR出水COD、 TN、TP质量浓度始终保持在26、14、0.28 mg·L^(-1)以下,达到《城镇污水处理厂污染物排放标准》一级A排放标准。高通量测序结果表明MPSR内微生物结构丰富,系统内好氧反硝化菌Thermomonas、Terrimonas、反硝化除磷菌Dechloromonas等多重功能微生物共存。MPSR内丰富的微生物结构使其在高悬浮物冲击下仍可以保持稳定的处理效果。

A pilot-scale micro-pressure swirl teactor(MPSR) was used to treat the effluent from the grit chamber of a sewage treatment plant in a new district of a northern city in China, the reactor pollutant treatment effects and pollutant removal characteristics at high suspended solids influent were inspected. The highthroughput sequencing was used to determine the microbial community structure in MPSR. The 450-day operation results showed that the average SS concentration in the influent of MPSR increased to about800 mg·L^(-1)from January to May and reached about 2 700 mg·L^(-1)from May to August due to the influences of the melting of snow and ice in spring and the summer rainfall. Based on the SPSS correlation analysis, a positive correlation occurred between water SS and COD with the pearson correlation of 0.682. The MLSS concentration in the system increased to 12 000 mg·L^(-1)due to high suspended solids inflow, while the MLVSS concentration basically maintained between 3 000 mg·L^(-1)and 5 000 mg·L^(-1), and SVI value decreased to 50 mL·g^(-1). At different influent loadings, COD, TN and TP concentrations in the effluent of MPSR were always below 26, 14and 0.28 mg·L^(-1), respectively, which met the first-level A emission standards of “urban sewage treatment plant pollutant emissions standard”. The results of high-throughput sequencing showed that the microbial structure in MPSR was abundant, and multiple functional microorganisms such as aerobic denitrifying bacteria Thermomonas, Terrimonas, and denitrifying phosphorus removing bacteria Dechloromonas coexisted in the system. The rich microbial structure in MPSR enables it to maintain a stable treatment effect under the impact of high suspended solids.