市政污泥接种焦化废水好氧降解能力及微生物群落演替的响应分析

焦化废水是毒性很大的典型工业废水,生物处理过程中需要微生物具备很强的适应能力.以探讨焦化废水对微生物的毒性抑制以及微生物对焦化废水的适应过程为目的,通过于焦化废水原水中接种市政污泥,在考察COD、苯酚、氨氮和硫氰化物等主要污染物指标降解的基础上,运用Illumina高通量测序平台分析降解过程微生物群落组成及多样性变化的响应关系.结果表明,接种了市政污泥的焦化废水培养16 h后COD开始下降,40 h时苯酚降解了97.14%,72 h时硫氰化物开始降解,96 h时硫氰化物浓度低于检测限,氨氮浓度随着硫氰化物的降解而升高.群落测序分析表明,不同培养阶段污泥中微生物表现出群落结构及丰度上的差异:在苯酚降解阶段,苯酚优势降解菌Acinetobacter、Pseudomonas的丰度增大,48 h总相对丰度为13.04%;在硫氰化物降解阶段,Sphingobacterium、Brevundimonas、Lysobacter、Chryseobacterium为主导菌属,96 h时其总相对丰度为16.13%;在144 h阶段,优势菌属则变为Fluviicola、Stenotrophomonas和Thiobacillus,总相对丰度为22.45%.由此认为,市政污泥克服了焦化废水中毒性成分的抑制作用之后能迅速适应环境,表现出微生物群落结构随着废水降解成分的变化而改变,环境因子和降解功能菌之间的竞争是群落结构演变的主要因素.

Aerobic Degradation and Microbial Community Succession of Coking Wastewater with Municipal Sludge

Coking wastewater is a typical industrial wastewater with high toxicity. Its treatment with biological processes is often challenging because it contains constituents inhibiting microbial activity. To study the inhibitory effect and possible acclimation of microbes in coking wastewater treatment, municipal sludge was inoculated into coking wastewater. Time-dependent concentrations of COD, phenol, ammonia nitrogen, and thiocyanide in coking wastewater were analyzed. The microbial community structure was investigated by the Illumina high-throughput sequencing technology during inoculation. The results showed that COD began to decrease after 16 h and 97.1% of phenol disappeared after 40 h. Thiocyanide began to degrade at 72 h and was undetectable after 96 h. Accordingly, the concentration of ammonia increased as the thiocyanide concentrations decreased. High-throughput pyrosequencing analysis showed that the microbial community structure and species richness varied at different culture stages. In the stage of phenol degradation, the abundance of Acinetobacter and Pseudomonas increased rapidly; the species richness was 13.04% of the community at 48 h. In the stage of thiocyanate degradation, Sphingobacterium,Brevundimonas,Lysobacter, and Chryseobacterium were the dominant bacteria and were 16.13% of the community at 96 h. At 144 h, Fluviicola,Stenotrophomonas, and Thiobacillus became the dominant species and were 22.45% of the community abundance. The results showed that municipal sludge can rapidly overcome the toxicity of coking wastewater because the pollutants are degraded rapidly. The microbial community structure changed as wastewater components were degraded. Environmental factors and the competition among bacteria played a key role in microbial community succession.