微生物菌剂联合填料对污水水体的脱氮效果及其水体中微生物群落结构的影响

EFFECT OF MICROBIAL AGENTS COMBINED WITH FILLERS ON DENITRIFICATION OF SEWAGE WATER BODY AND THE STRUCTURE OF MICROBIAL COMMUNITY IN WATER

先通过生活污水水体净化的静态实验比较筛选市场上调研的4种主流微生物菌剂,再通过改进版本的A^(2)O-MBR工艺研究微生物菌剂联合填料对污染水体的脱氮效果及其反应器内微生物群落结构的变化。结果显示:相较于其余3种菌剂而言,J菌剂对生活污水水体净化效果最佳,且硝化速率显著高于其他3种菌剂(P<0.05);生活污水水体净化流动实验A^(2)O-MBR反应器中,生物绳和玄武岩2组填料在启动第12天时挂膜成功且表面形成稳定生物膜。在NH^(+)_(4)-N去除上,生物绳、玄武岩2组填料在形成微生物膜后期的NH^(+)_(4)-N去除率分别为73.06%和71.1%,且相较于膜形成前的NH^(+)_(4)-N去除率均提高了20%左右;高通量测序结果表明,4组生物膜样品中门水平上优势物种均为变形菌门和拟杆菌门,且生物绳填料和玄武岩填料上的变形菌门丰度分别为74.8%和68.7%,拟杆菌门丰度分别为8.37%和6.50%。2组填料在属分类水平上物种差异性较大,玄武岩填料上的优势菌属为unidentified Nitrospiraceae,平均丰度为15.8%,生物绳填料上的优势菌属为Candidatus_Nitrotoga,平均丰度为25.56%。4组样品中均检测到Nitrosomonas的存在,且在好氧池BO、XO组别中占比分别高达2.34%和3.04%,表明系统具有良好的硝化性能,这与生活污水中的NH^(+)_(4)-N、NO_(2)^(-)-N的去除效果相一致。

In recent years,with the rapid progress and development of China’s social economy and the accelerating process of urbanization,the input of a large number of nutrients such as nitrogen and phosphorus has made the problem of water pollution increasingly serious.The application of microbial agents to treat polluted water quality has attracted more and more attention.In this study,four mainstream microbial agents investigated in the market were compared and selected through the static experiment of domestic sewage water purification,and then the denitrification effect of microbial agents combined with fillers on polluted water and the changes of microbial community structure in the reactor were studied through the improved version of A^(2)O-MBR process.The results showed that compared with the other three kinds of agents,Jiangxi water transfer agent had the best purification effect on domestic sewage water,and the nitrification rate was significantly higher than the other three kinds of bacteria(P<0.05);Domestic sewage water purification flow experiment in A^(2)O-MBR reactor,two groups of fillers,biological rope and basalt,were successfully coated on the 12th day of startup,and a stable biofilm was formed on the surface.In terms of NH^(+)_(4)-N removal,the NH^(+)_(4)-N removal rates of biological rope and basalt fillers in the late stage of microbial membrane formation were 73.06%and 71.1%respectively,and the NH^(+)_(4)-N removal rates were increased by about 20%compared with those before membrane formation;High throughput sequencing results showed that the dominant species at the phylum level in the four groups of biofilm samples were Proteobacteria and Bacteroidota,and the abundance of Proteobacteria on biological rope filler and basalt filler were 74.8%and 68.7%respectively,and the abundance of Bacteroidea was 8.37%and 6.50%respectively.There are great species differences between the two groups of fillings at the genus classification level.The dominant bacterium on basalt fillings is unidentified nitrospiraceae,with an average abundance of 15.8%,and the dominant bacterium on biological rope fillings is Candidatus_Nitrotoga,with an average abundance of 25.56%.Nitrosomonas was detected in all four groups of samples,and accounted for 2.34%and 3.04%respectively in the BO and XO groups of the aerobic tank,indicating that the system has good nitrification performance,which is consistent with the removal effect of NH^(+)_(4)-N and NO_(2)^(-)-N in domestic sewage.