基于零价铁强化含抗生素的废水生物脱氮处理效能及机理研究

污水生物脱氮处理对防控水体富营养化具有重要意义。抗生素的滥用及在机体中的低效率代谢导致抗生素排放至污水并进入污水处理厂，对生物脱氮产生潜在威胁。本项目拟利用零价铁强化含抗生素的废水生物脱氮处理效能，通过影响因素研究确定最优运行条件，探究抗生素抑制下零价铁对氮的转化及N2O生成的影响，并进一步探究零价铁对含抗生素废水生物脱氮的强化机理。通过零价铁对抗生素的非生物及生物多种降解途径的影响研究，探明引起抗生素最大降解贡献的途径，阐明抗生素在污泥系统中浓度分布的变化对脱氮的影响；通过研究零价铁对微生物表面结构尤其是细胞膜特性的影响，分析抗生素跨膜进入胞内的能力变化及与脱氮效果的关系；再者，通过铁对微生物胞内氧化应激水平的及脱氮代谢过程的调控影响研究，进一步阐释抗生素影响下零价铁强化脱氮的分子生物学机制。本项目研究成果可为污水处理厂应对抗生素或其他有毒有机污染物引起的运行风险提供理论和实践依据。

Biological nitrogen removal from wastewater is significant to protect the waterbody from eutrophication. The abuse of antibiotics and their inefficient metabolism in the bodies cause them entering the wastewater treatment plant via sewage, which poses a potential threat to biological nitrogen removal. This project is aimed to enhance the biological nitrogen removal efficiency from antibiotics-containing wastewater by applying the zero-valent iron. The optimal operation parameters will be determined via investigation of influence factors, and the effect of zero-valent iron on nitrogen transformation and N2O generation will be explored during the antibiotics-restrained nitrogen removal process. Moreover, the mechanisms of biological removal enhancement from antibiotic-containing wastewater will be unclosed. By studying the impact of zero-valent iron on antibiotics degradation via abiotic and biotic pathways, the main pathway contributing the major antibiotic degradation is distinguished, and the variation of antibiotic concentration distribution in activated sludge system affecting on nitrogen removal is revealed. The ability changes of antibiotic crossing the cell membrane and its relationship with nitrogen removal will be analyzed through detecting the iron-induced changes of microbial surface structures especially the membrane characteristics. Furthermore, the iron-regulated behaviors of intracellular oxidative stress level and nitrogen removal metabolic process elucidate the molecular biological mechanism of the impact of iron on the improvement of antibiotic-depressed nitrogen removal. The result of this project will provide the WWTP a theoretical and practical reference to deal with the underlying operational risks induced by the antibiotics and other toxic organic pollutants.