CEM-UF组合膜-硝化/反硝化系统处理低C/N废水及种群结构分析

本研究采用具有氨氮富集分离特性的阳离子交换膜-超滤(CEM-UF)组合膜与硝化/反硝化结合处理低C/N废水,考察该系统不同流量比下低C/N废水的硝化、反硝化脱氮特性,并通过对硝化、反硝化活性污泥进行16Sr DNA高通量测序,分析功能微生物群落结构特征.结果表明,系统进水TN为60 mg·L-1,COD/TN为2.65下,各流量比下硝化均有较好效果,平均氨氮去除率为98.7%,流量比值由1∶2上升到1∶6过程中,反硝化m(COD)/m(NO-3-N)随之升高,1∶6时平均硝氮去除率达到最高,为86.28%,系统总氮去除率由22.56%上升到46.8%.Illumina高通量测序结果表明,硝化污泥中可以固氮的Proteobacteria菌门占30.9%,重要的亚硝酸盐氧化菌Nitrospirae菌门占3.06%,属水平上检测到氨氧化菌(AOB)Nitrosomonas和Nitrosospira,亚硝酸盐氧化菌(NOB)Nitrospira和Nitrobacter,AOB与NOB菌比例较高,与硝化反应器中较好的硝化效果相一致.反硝化污泥中Proteobacteria菌门占主导地位(53.13%),其次是Bacteroidetes菌门(10.93%),在属的水平上检测到Dechloromonas、Thauera、Castellaniella、Alicycliphilus、Azospira、Comamonas、Caldilinea和Saccharibacteria多种具有反硝化脱氮作用的相关菌属,反硝化菌所占比例为25.91%,反硝化污泥中具有反硝化功能的微生物丰富,反硝化效果良好.

Analysis of Low C/N Wastewater Treatment and Structure by the CEM-UF Combined Membrane-Nitrification/Denitrification System

In this study, a CEM-UF composite membrane with ammonia nitrogen enrichment and separation characteristics was combined with nitrification/denitrification to treat low C/N wastewater. The denitrification characteristics of low C/N wastewater at different flow ratios were investigated, and the structural characteristics of functional microbial communities in nitrifying and denitrifying activated sludge were analyzed by 16Sr DNA high-throughput sequencing. The results showed that influent TN was 60 mg·L^-1, COD/TN was 2.65, the nitrification effect of each flow rate was good, and the average ammonia nitrogen removal rate was 98.7%. When the flow ratio increased from 1:2 to 1:6, the m(COD)/m(NO₃^--N) of denitrification was increased, and the removal of average nitrate nitrogen reached its highest level at 1:6, which was 86.28%, and the removal of total nitrogen increased from 22.56% to 46.8%. An analysis of Illumina sequencing showed that nitrogen fixing bacteria Proteobacteria accounted for 30.9%, and the important nitrite oxidizing bacteria, Nitrospirae, accounted for 3.06%. At the genus level, Nitrosomonas and Nitrosospira, belonging to the ammonia oxidizing bacteria (AOB) category and Nitrospira and Nitrobacter, belonging to the nitrite oxidizing bacteria (NOB) category were detected. The ratio of AOB and NOB bacteria was high, which is consistent with good nitrification in the nitrification reactor. The dominant bacteria in denitrification sludge were Proteobacteria (53.13%), followed by Bacteroidetes (10.93%). A variety of bacteria related to denitrification were detected at the genus level, such as Dechloromonas, Thauera, Castellaniella, Alicycliphilus, Azospira, Comamonas, Caldilinea, and Saccharibacteria. The proportion of denitrifying bacteria was 25.91% as denitrifying bacteria microbial species were rich in the denitrifying sludge, giving a good denitrification effect.