A/O-MBBR工艺处理生活污水性能及菌群结构

Performance and microbial community of anoxic/oxic-moving bed biofilm reactor (A/O-MBBR) process treating domestic sewage

采用设计规模为100m^(3)/d的一体化缺/好氧-移动床生物膜反应器(A/O-MBBR)处理实际生活污水,通过265d的中试研究考察了该工艺在多因素扰动下的除碳和脱氮性能,并对不同运行阶段微生物群落结构的动态变化进行了研究.结果表明,一体化A/O-MBBR系统具有良好的COD去除效果和脱氮性能.当好氧池溶解氧(DO)浓度和进水碳氮比(COD/N)分别为2.5~3.5mg/L和(7.9±2.0)时,COD、NH_(4)^(+)-N和TN去除率分别达到(93.3±5.4)%、(99.1±0.6)%和(67.9±10.5)%.Proteobacteria、Bacteroidetes和Chloroflexi在不同运行时期均有较高的相对丰度,保证了有机物的高效去除.A/O-MBBR系统脱氮功能菌在运行初期主要分布于活性污泥中,且相对丰度较低.长期运行后,生物膜与活性污泥中均同时检出大量硝化菌和反硝化菌.其中,相对丰度最高的硝化菌为Nitrospira,主要分布于生物膜上(19.48%~28.05%).反硝化菌则以Thauera、Terrimonas和Dokdonella等为主.

An integrated anoxic/oxic-moving bed biofilm reactor(A/O-MBBR)with a scale of 100m^(3)/d was adopted to treat domestic sewage.The performance of carbon and nitrogen removal under multi-factor disturbances was investigated through a 265 day pilot study.Furthermore,the dynamic changes of the microbial community structure in different treatment phases were studied.Results revealed that the integrated A/O-MBBR system showed excellent COD and nitrogen removal performance.Under the conditions of 2.5~3.5mg/L dissolved oxygen(DO)in aerobic tank and influent carbon to nitrogen(COD/N)ratio of(7.9±2.0),the removal rates of COD,NH_(4)^(+)-N and TN could reach(93.3±5.4)%,(99.1±0.6)%,(67.9±10.5)%,respectively.Proteobacteria,Bacteroidetes and Chloroflexi were abundant in different running phases,which ensured the efficient removal of organic matters.In the initial running phase,denitrification functional bacteria of A/O-MBBR system were mainly distributed in activated sludge with relatively low abundance.After a long-term operation,a large number of nitrifying and denitrifying bacteria were simultaneously detected in both biofilm and activated sludge,and the nitrifying bacteria with the highest relative abundance was Nitrospira,which was mainly distributed on the biofilm(19.48%~28.05%).Meanwhile,Thauera,Terrimonas and Dokdonella were the dominant denitrifying bacteria in the later running phase.