生物膜层DO浓度对MABR中异养硝化-好氧反硝化的影响  

Effects of Dissolved Oxygen Concentrations on Heterotrophic Nitrification-Aerobic Denitrification of MABR

作　　者：康宝文 肖芃颖[1] 周靖 袁港 郭雷 KANG Baowen;XIAO Pengying;ZHOU Jing;YUAN Gang;GUO Lei(School of Chemistry and Chemical Engineering,Chongqing University of Technology,Chongqing 400054,China)

机构地区：[1]重庆理工大学化学化工学院,重庆400054

出　　处：《环境科学研究》2021年第10期2397-2404,共8页Research of Environmental Sciences

基　　金：国家自然科学基金项目(No.51708077);重庆市自然科学基金项目(No.cstc2020jcyj-msxmX0566);重庆市教委科学技术研究计划项目(No.KJQN202001138)。

摘　　要：高浓度氨氮(NH_(4)^(+)-N)废水的好氧生物处理是一个高氧需求过程.膜曝气生物膜反应器(membrane aerobic biofilm reactor,MABR)因其高氧利用率、低能耗优势在高氨氮废水处理中具有重要应用潜力.通过启动贯通式MABR接种异养硝化-好氧反硝化(heterotrophic nitrification and aerobic denitrification,HN-AD)脱氮混合菌液处理高氨氮模拟废水,调节进气量实现生物膜层不同溶解氧(DO)浓度,考察生物膜层DO浓度对MABR脱氮性能、HN-AD菌多样性及其脱氮功能基因的影响.结果表明:①MABR中仅生物膜内层DO浓度随进气量的增加而提升,生物膜外层DO浓度始终保持为0 mg/L;高DO浓度下反应器NH_(4)^(+)-N、总氮(TN)去除率相比低DO浓度分别增加了28.15%和24.18%,提高生物膜内层DO浓度强化MABR脱氮性能.②高通量测序分析表明,HN-AD菌是MABR中的脱氮功能微生物,研究获得假黄褐藻属(Pseudofulvimonas)、脱氮副球菌属(Paracoccus)、鞘氨醇杆菌属(Sphingobacterium)和不动杆菌属(Acinetobacter)等共13种HN-AD菌属,其总相对丰度在低、中和高DO浓度下分别为12.97%、19.05%和22.01%,说明提高生物膜内层DO浓度促进了HN-AD菌属的富集.③PICRUSt1功能基因预测发现,MABR中HN-AD菌的好氧反硝化功能基因(napA、napB)总相对丰度在低、中和高DO浓度下分别为0.00013‰、0.019‰和0.060‰,说明提高MABR生物膜内层DO浓度加快了HN-AD菌的好氧反硝化进程,促进了MABR中HN-AD过程的实现.研究显示,通过调节进气量实现生物膜内层不同DO浓度,可以强化MABR脱氮性能,提高HN-AD菌属富集程度,促进MABR中HN-AD过程的实现.The aerobic biological treatment of high-concentration ammonia nitrogen(NH_(4)^(+)-N)wastewater is a process that consumes a lot of oxygen.The membrane aerated biofilm reactor(MABR)has important application potential in the treatment of wastewater with high ammonia nitrogen due to its high oxygen utilization rate and low energy consumption.In this study,the mixed bacterial solution with the function of heterotrophic nitrification-aerobic denitrification(HN-AD)was inoculated into the through-type MABR to treat high ammonia nitrogen synthetic wastewater.Different dissolved oxygen(DO)levels in the biofilm layer were achieved by adjusting the inlet gas flow to investigate the effect of the DO concentration in the biofilm layer on the nitrogen removal performance of the MABR,the diversity of the HN-AD bacteria and its nitrogen removal function genes.The results showed that:(1)With the increase of inlet gas flow in the MABR,the DO concentration of the inner layer biofilm increased,while DO concentration of the outer layer biofilm remained at 0 mg/L at different inlet gas flow rates.The removal rate of NH_(4)^(+)-N and TN in the reactor under high DO level in the inner layer of the biofilm increased by 28.15%and 24.18%,respectively,compared with the low DO level.The increase of DO concentration in the inner layer of the biofilm strengthened the nitrogen removal performance of MABR.(2)High-throughput sequencing analysis showed that HN-AD bacteria were denitrification function microorganisms in the MABR,and 13 species of HN-AD bacteria including Pseudofulvimonas,Paracoccus,Sphingobacterium,Acinetobacter,etc.were obtained.The total relative abundance of HN-AD bacteria was 12.97%,19.05%and 22.01%at low,medium and high DO levels,respectively.It shows that increasing the DO concentration in the inner layer of the biofilm promoted the enrichment of HN-AD bacteria.(3)Furthermore,according to PICRUSt1 functional gene prediction,the total relative abundance of aerobic denitrification functional genes(napA,napB)in the MABR were 0.

关 键 词：MABR 异养硝化-好氧反硝化 生物膜层DO浓度 微生物多样性 高氨氮废水 

分 类 号：X703.1[环境科学与工程—环境工程]