成膜好氧反硝化菌协同固体缓释碳强化生物膜脱氮效能及机理

污水厂尾水深度脱氮是减少受纳水体氮负荷的重要途径。利用好氧反硝化菌强化尾水脱氮是目前水处理领域的研究热点，但存在功能菌易流失、尾水中碳源不足等问题。固体缓释碳既能够为脱氮功能菌提供碳源，又可以作为生物膜载体，但也因大量定植的非反硝化菌群竞争碳源，限制了反硝化菌的碳源利用率。申请人前期工作中发现，成膜反硝化菌能有效定植到生物膜上。推测成膜好氧反硝化菌协同固体缓释碳强化尾水脱氮能够克服上述难题，具有潜在的应用前景。本项目拟在尾水脱氮系统中应用成膜好氧反硝化菌株DC-1协同固体缓释碳PBS强化生物膜脱氮。期望从膜形成与稳定特征、群感效应，胞外聚合物特性、DC-1定植丰度及菌群互作关系等角度，阐明DC-1在PBS载体膜上的定植效率，解析协同强化对膜形成与稳定的影响及机理；从氮平衡、脱氮基因丰度及脱氮菌群等角度，探究协同强化生物膜脱氮效果与机理。研究结果为攻克尾水深度脱氮技术难题提供新的思路和实践。

Deep nitrogen-removal in tail water from wastewater treatment plants is an important way to reduce nitrogen loads of receiving waters. The use of aerobic denitrifiers to enhance nitrogen-removal in tail water is currently a research hotspot in the field of water treatment, but there are problems such as easy loss of functional bacteria and insufficient carbon sources in tail water. Solid slow-release carbons can not only provide carbon sources for denitrification functional bacteria, but also serve as biofilm carriers，However, due to the large number of non-denitrifiers colonizing to compete for carbon sources, it limits the carbon source utilization rate of denitrifiers. The applicant found that the biofilm-forming denitrifiers could be effectively colonized on biofilms. It is speculated that the biofilm-forming aerobic denitrifiers coupling with solid slow-release carbons bioaugmented nitrogen-removal in tail water could overcome the above problems and have potential application prospects. This project intends to apply the biofilm-forming aerobic denitrifier, strain DC-1, coupling with the solid slow-release carbon, PBS, to enhance the nitrogen-removal efficiency of biofilms in the tail water nitrogen-removal systems. It is hoped to elucidate the colonization efficiency of strain DC-1 on PBS carrier biofilms and analyze the effect and mechanism of synergistic bioagumentation on biofilm formation and stability from these aspects, such as the characteristics of biofilm-formation and -stability, quorum sensing, the traits of extracellular polymeric substances, the colonization abundances of strain DC-1, bacterial interaction relationships and others. The effect and mechanism of synergistic bioagumentation on nitrogen removal of biofilms would be explored from the perspectives of nitrogen balance, the abundances of denitrification genes and denitrification flora.The research results would provide new ideas and practices for overcoming the technical problems of deep nitrogen-removal in tail water.