亚硝酸氧化细菌N. defluvii在主流SNAD系统中的受迫生存机制研究

主流SNAD工艺是实现污水处理厂能量自给自足的关键技术之一，其重点是抑制低氮生境优势NOB种属N. defluvii。项目前期结果表明，即使亚硝化率>90%、好氧SRT<2天，N. defluvii大量存在，推测该细菌具有除亚硝酸盐氧化外的代谢功能。外界条件改变时，N. defluvii极易恢复好氧硝化活性，严重威胁SNAD工艺稳定性。因此，本项目将深入研究N. defluvii潜在代谢途径，揭示N. defluvii在主流SNAD系统中受胁迫生存机制。同时研究外源NOB对主流SNAD控制参数的影响，并指导设计一套动态控制策略。本项目有望为探索N. defluvii新代谢途径、优化主流SNAD工艺调控策略、实现污水厂能量自给自足提供理论依据和技术支持。

Mainstream SNAD (Simultaneous partial Nitrification, Anammox and Denitrification) is a key technology to achieve energy neutral in the future wastewater treatment plants. The key of mainstream nitritation is to inhibit N. defluvii, a dominant NOB in the conventional wastewater treatment plant. Our previous studies showed that N. defluvii was still dominant bacteria with a nitrite accumulation rate > 90% and aerobic SRT < 2 days, so it could be speculated that N. defluvii had another metabolic pathway. Its activity of nitrite oxidation will be easy to recover with a change of environment, which will pose a serious threat to the mainstream SNAD process. Therefore, the potential metabolic pathways and cell adaption mechanisms of N. defluvii will be investigated in a SNAD system. Meanwhile, the effect of NOB immigration on the mainstream SNAD system will be studied to develop an integrated strategy to inhibit growth of the immigrant NOB. This project will be meaningful for investigating the unknown metabolic pathways of N. defluvii, optimizing its control strategies, and further realizing energy sufficiency of the future wastewater treatment plants.