焦化废水中多环芳烃生物降解的动态过程与功能微生物菌群的响应特征

Coking wastewater was typical industrial wastewater with high concentration of polycyclic aromatic hydrocarbons (PAHs). Currently little is known about the PAHs biodegradation dynamics in the coking wastewater biological treatment. And the response characteristics of functional microbiology groups involved in the biological treatment process of coking wastewater have not yet been precisely characterized. The unknown PAHs biodegradation dynamics and response characteristics of functional microbiology groups hinder the coking wastewater biological treatment, which induce the control of PAHs in coking wastewater with limited efficiency. In this project we will separately study the different units (Anaerobic, Hydrolysis, Oxic) in the biological treatment process of coking wastewater. To characterize the dynamic process of 16 priority PAHs during the biodegradation, the composition and concentration of PAHs will be determined by SPME-GC/MS recombinant techniques. The response characteristics of functional microbiology groups in different units will be examined by 16S rDNA or functional genes clone library, quantitative real-time PCR, respectively. Phylogenetic and statistical analysis will be used to definite a "core functional microorganisms", which has never been reported and completely unknown on the key PAHs biodegradation microorganisms in coking wastewater. Further more, the relationships between PAHs biodegradation dynamics and the biodegradative potential of functional microbiology groups involved in coking wastewater will be illustrated based on the abundances of functional gene. This project would provide new theories on the unit design, process control and directorial screening of functional microbiology in coking wastewater with high PAHs concentration.

焦化废水是含高浓度多环芳烃工业废水的典型代表。目前对焦化废水生物处理过程多环芳烃的降解动态过程认识有限，对执行降解功能的微生物菌群响应特征更缺乏深入了解，导致对焦化废水多环芳烃生物处理工艺的控制带有盲目性。本项目拟对焦化废水生物处理过程的各工艺单元（厌氧、水解、好氧）为研究对象，应用SPME-GC/MS联用技术分析焦化废水生物处理过程16种优控多环芳烃的组成与浓度，阐述废水中多环芳烃生物降解的动态变化规律；通过构建16S rDNA或功能基因克隆文库以及功能基因定量PCR技术，阐明功能微生物菌群响应的结构与功能特征：解析各工艺单元功能微生物菌群的结构，提出一个降解含高浓度多环芳烃废水的"核心功能菌群"，并结合功能基因定量分析，探求焦化废水中多环芳烃生物降解动态与功能微生物菌群代谢潜能的相关性。本项目有望为焦化废水中多环芳烃生物降解的工艺设计、过程监控以及功能微生物的定向筛选提供新的理论依据。

焦化废水是含高浓度多环芳烃工业废水的典型代表。了解焦化废水生物处理过程多环芳烃的降解动态，以及执行降解功能的微生物菌群特征，有利于焦化废水多环芳烃生物处理工艺的控制。为阐明焦化废水生物处理系统的微生物菌群结构以及探讨焦化废水水质特征和工程运行条件对微生物的影响，本项目对焦化废水生物处理过程的各工艺单元（厌氧、水解、好氧）为研究对象，首先应用SPME-GC/MS联用技术分析焦化废水生物处理过程18种优控多环芳烃的组成与浓度，阐述废水中多环芳烃生物降解的动态变化规律。结果表明PAHs广泛存在焦化废水的原水、各级处理出水、焦化污泥和外排气中。整个废水处理过程对水相PAHs的去除率可达97%以上；污泥吸附是该类物质去除的主要途径，例如高分子量PAHs通过污泥吸附去除的量可达76%。接着基于16S rDNA高通量Miseq测序技术，揭示了在不同生物反应器中存在独特的微生物组成，其中Pseudomonas, Comamonas 和 Thiobacillus 三个主要属分别是厌氧生物反应器, 一级好氧反应器和二级好氧反应器中的最优势属，并且它们所占的丰度分别是72.59, 56.75 和 27.82 %。 冗余分析Redundancy Analysis (RDA) 结果表明这三个生物反应器的功能菌群主要与氰化物，酚类物质，氨氮具有强相关性。最后提出Pseudomonas和Comamonas 是执行焦化废水中PAHs生物降解的最主要功能类群。本项目的研究成果有望为焦化废水中多环芳烃生物降解的工艺设计、过程监控以及功能微生物的定向筛选提供新的理论依据。