印染废水溶解性有机氮生变规律及基于零价铁的优化调控去除研究

印染行业氮的排放总量大，其高效削减对防护水体富营养化意义重大。印染废水中的氮主要来源于偶氮染料及尿素，导致印染废水呈较高浓度溶解性有机氮（DON）的污染特征，因此DON的高效去除与调控成为生物脱氮的关键。本项目拟通过研究进水有机氮的降解速率、降解产物及氮的迁移转化，获悉印染废水有机氮的生变规律以及有机氮降解的限制因子；其次，通过研究微生物在印染废水处理过程中受到的氧化应激及胞外聚合物的分泌与释放，解析微生物含氮代谢产物的生成机制；此外，通过在生化阶段引入零价铁的调控策略，基于提高生物脱氮系统中外源性有机氮的降解并同时降低微生物含氮代谢产物的内源性有机氮生成的思路，实现优化调控DON及总氮的去除，并开展相关机理研究。研究成果将从有机氮脱除角度丰富完善印染废水生物脱氮处理内涵，为印染废水高效脱氮提供科学依据及技术支撑。

The total amount of nitrogen emissions in the printing and dyeing industry is large, and its efficient reduction is of great significance to protect the waterbody from eutrophication. The nitrogen in printing and dyeing wastewater is mainly derived from azo dyes and urea, making the printing and dyeing wastewater have the pollution characteristics of high concentration of dissolved organic nitrogen (DON). Therefore, the efficient removal and regulation of DON has become the key to biological nitrogen removal. This project intends to learn about the fate of DON in printing and dyeing wastewater and the limiting factors of organic nitrogen degradation via investigating the degradation efficiency, degradation products of influent DON, and the migration and transformation of nitrogen species; Then, by studying the oxidative stress and extracellular polymer secretion and release of microorganisms during the process of printing and dyeing wastewater treatment, the formation mechanism of nitrogen-containing metabolites is analyzed; In addition, by adopting the control strategy of introducing zero-valent iron into the biological treatment stage, based on the idea of simultaneously improving the degradation of exogenous organic nitrogen and reducing the production of endogenous organic nitrogen in microbial nitrogen-containing metabolites in the biological nitrogen removal system, the enhanced removal of DON and TN is expected to achieve, and the relevant mechanism research is carried out. The results of this project will enrich the connotation of biological nitrogen removal of printing and dyeing wastewater from the perspective of organic nitrogen removal, and provide a scientific basis and technical support for the efficient removal of nitrogen from dyeing and printing wastewater.