高氨氮负荷膜生物反应器强化去除毒害有机物及其机制研究

Toxic organic compounds and high concentration of ammonia nitrogen in wastewater seriously threaten the ecological security. This project aims to use the membrane bioreactor (MBR), which has advantages in the removal of ammonia nitrogen and toxic organic compounds, to treat high ammonia wastewater and simultaneously strengthen the removal efficiency of toxic organic compounds. The effects of toxic organic compounds on microbial nitrification will be studied. In addition, the pathways of ammonia metabolism and the metabolites of toxic organic compounds will be investigated to determine the contribution of heterotrophic metabolism, nitrifying activity and abiotic nitration on the removal of toxic organic compounds. Illumina high-throughput sequencing, metagenomics analysis and real time polymerase chain reaction will also be applied to reveal the changes in diversity and abundance of functional genes, and the relationship between functional genes distribution and microbial community structure, so as to explore the potential molecular ecological mechanisms of enhanced removal of toxic organic compounds in MBR with high ammonia load. Lastly, the operating parameters of MBR will be optimized to improve the removal efficiency of ammonia nitrogen and toxic organic compounds. This project will provide new theoretical and practical supports for the efficient and economical treatment of wastewater with high concentration of ammonia and toxic organic compounds which produced from pharmaceutical, coking, and leather industry.

废水中存在的毒害有机污染物和高浓度氨氮，严重威胁了生态安全。本课题拟利用膜生物反应器（MBR）在高氨氮废水处理及毒害有机物去除方面具有的优势，在实现高浓度氨氮去除的基础上，强化对毒害有机污染物的去除效率。通过氨氮的转化途径、毒害有机污染物代谢产物分析等，揭示毒害有机物存在下对微生物硝化作用的影响，阐明异养菌生长代谢、污泥硝化活性和非生物硝基化反应在毒害有机物去除中的贡献。通过Illumina高通量测序、宏基因组学分析、实时定量PCR等分子生物学手段，分析运行过程中高氨氮负荷MBR中功能基因丰度和多样性的变化特征，以及功能基因分布与菌群结构之间关系，揭示高氨氮负荷MBR反应器强化去除毒害有机物的微生物学机制。在此基础上，优化工艺条件，实现MBR反应器对高浓度氨氮及毒害有机物的高效去除。本项目的实施将为我国制药、焦化和制革等行业中高氨氮、高毒废水的处理提供科学依据和理论支持。

有机废水中的毒害有机污染物和高浓度氨氮严重威胁了生态安全。本项目首先研究了MBR反应器维持高效、稳定运行所能去除的最大氨氮负荷，并在此基础上探究了盐浓度、碳氮比、磺胺甲恶唑等对高氨氮负荷MBR运行的影响以及高氨氮负荷MBR强化去除磺胺甲恶唑的机制，进一步借助Illumina高通量测序、宏基因组学分析等分子生物学方法探究了高氨氮负荷MBR微生物功能菌群与反应器运行参数之间的关系，解析了高氨氮负荷MBR反应器中的微生物学机理。研究结果表明：（1）优化运行参数，MBR反应器最大氨氮去除负荷可达4.78 kg NH4+-N/m3·d；（2）高氨氮负荷MBR耐受的NaCl盐浓度达到4%；（3）MBR反应器可实现高浓度氨氮（1000 mg/L）和高浓度磺胺甲恶唑（100 mg/L）的同步去除；（4）对磺胺甲恶唑去除起主导作用的是污泥的硝化过程；（5）不同条件下氨氧的去除是由不同类型的氨氧化细菌主导完成的。本项目的研究成果可为高盐、高氨氮、高毒废水的治理提供科学依据和理论支持。