耐盐染料降解菌群驯化及其微生物群落分析

Domestication of dye-degrading salt tolerant bacteria and the community structure analysis

为进一步提升对含盐染料废水的处理效率,在3组SBR反应器(R1、R2、R3)中分别投加NaCl、还原蓝4(VB4)、NaCl+VB4,并逐步提高其投加浓度,探究在不同盐度和染料浓度的驯化条件下,活性污泥对模拟废水的处理效果以及微生物群落的组成结构。结果表明:盐度增加至3%时,R1和R3的COD去除率开始大幅降低;在仅投加染料的反应器R2中,COD的平均去除率为95.5%;各反应器的氨氮平均去除率在90%以上。随着盐度和染料浓度的提升,系统稳定性下降。盐度和染料质量浓度分别达到1%、40 mg/L时,污泥对染料的脱色性能开始下降。高通量测序分析结果表明,随着盐度和染料的增加,活性污泥的微生物群落多样性降低,降解COD及染料的功能菌群主要受系统含盐量的影响,氨氮降解菌群受环境变化的影响不大。在各反应器运行过程中,norank-f-norank-o-saccharimonadales、Propioniciclava、Micropruina3个菌属的丰度最高,对盐和染料表现出较好的耐受性,为含盐印染废水处理系统的优势菌群。

In order to further improve the treatment efficiency of salinity dye wastewater,NaCl,reduced blue 4(VB4)and NaCl+VB4 were added into three groups of SBR reactors(R1,R2 and R3),and their concentration was gradually increased.The treatment effect of activated sludge on simulated wastewater and microbial community structure were investigated under different conditions of salinity and dye concentration.The results showed that the COD removal rate of R1 and R3 started to decrease significantly when the salinity increased to 3%.The average COD removal rate was 95.5%in R2,where only dye was added.The average removal rate of ammonia nitrogen was above 90%in all reactors.The stability of the system decreased with the increase of salinity and dye concentration.The de⁃colorization performance of sludge on dyes began to decline when the salinity and dye mass concentration reached 1%and 40 mg/L,respectively.The results of high-throughput sequencing analysis showed that the diversity of acti⁃vated sludge microbial community decreased with the increase of salinity and dye,and the functional bacteria for de⁃grading COD and dye were mainly affected by the salinity of the system,while the ammonia-nitrogen degrading bac⁃teria were not affected by environmental changes.During the operation of each reactor,norank-f-norank-o-saccharimonadales,Propioniciclava and Micropruina had the highest abundance and showed better tolerance to sa⁃linity and dye,and were the dominant bacteria in the treatment system of saline printing and dyeing wastewater.