反硝化厌氧甲烷氧化碳减排耦合厌氧氨氧化共脱氮机制及工艺调控

The organic pollutants in municipal sewage contain large amounts of chemical energy, which could be captured and subsequently converted to renewable energy through anaerobic digestion. This enables energy self-sufficient and carbon-neutral operation of wastewater treatment plants to achieve sustainable sewage treatment, which meets the strategic demands of greenhouse gas mitigation and ecological environmental protection energy of the 13th national five-year plan. However, the sustainable development of sewage treatment is greatly limited by the competition of organic carbon between energy recovery and nitrogen removal from wastewater, and also restricted by massive methane emission during anaerobic energy recovery. This project will combine the microorganisms with complementary functions of nitrogen removal— denitrifying anaerobic methane oxidation and anaerobic ammonium oxidation. The interaction and synergic competition among functional microorganisms will be investigated to develop coupling and matching mechanism; membrane biofilm reactor will be designed and optimized, the fast start-up strategy of coupling process will be established and the operation parameters will be optimized. The biofilm structure, the microbial population and the substrate distribution profile in the biofilm will be investigated to develop a dynamic biofilm model, and then the model will be used to simulate and optimize the operating conditions, to provide guide for operation and regulation of the coupling process and construct a high efficiency nitrogen removal and methane emission mitigation process. This project will effectively solve competition of organic carbon between energy production and nitrogen removal, maximise energy recovery from wastewater, and use methane as resource to reduce greenhouse gas emissions, which will make positive contributions to sustainable wastewater treatment.

城市污水中有机污染物蕴含丰富的能量，通过有机物的捕获和厌氧消化回收可再生能源，达到污水处理能源自给和碳中和运行，实现污水处理可持续发展，符合国家“十三五”温室气体减排和生态环境保护的战略需求。然而，污水高效脱氮与能量回收之间的有机碳竞争和厌氧能源回收过程中溶解甲烷大量无序排放限制了可持续污水处理的发展。本课题拟将脱氮功能互补的反硝化厌氧甲烷氧化和厌氧氨氧化微生物耦合，研究功能微生物之间交互作用规律，建立耦合匹配机制；优化设计膜生物膜反应器，开发耦合工艺快速挂膜启动策略，优化工艺运行与调控；解析生物膜结构、微生物种群和膜内基质分布规律，建立动态生物膜模型，模拟优化操作条件，指导耦合工艺运行和调控，构建高效脱氮同步甲烷减排工艺，有效解决高效脱氮与能源回收之间的有机碳竞争，最大限度实现废水中的能源回收，同时资源化利用溶解甲烷，减少温室气体排放，为可持续污水处理做出积极贡献。

反硝化厌氧甲烷氧化（DAMO）耦联反硝化和厌氧甲烷氧化过程，能够为污水生物脱氮新工艺的设计与发展提供契机。揭示DAMO功能微生物的脱氮潜能及代谢机理并建立工艺调控策略对加快其实际应用具有重要的推动作用。本项目构建了节能高效的DAMO脱氮体系，解析了DAMO功能微生物代谢途径机制，推动了DAMO工程化应用，并揭示了其在生物地球元素循环中的关键作用。.成功地富集了DAMO耦合Anammox培养物；构建了适用于DAMO耦合Anammox悬浮污泥形式的脱氮工艺，即膜曝气膜生物反应器（MAMBR），在启动200天内到达了2500 mg N/L/d的TN去除速率；基于悬浮耦合系统建立了DAMO絮状污泥脱氮过程的数值模型，解析了DAMO微生物生长特征并提出了脱氮性能优化的策略；探索了“三段进水法”启动策略运行膜生物膜反应器（MBfR），显著地缩短了启动时间并提升了TN去除速率。.构建了基于亚硝酸盐型厌氧甲烷氧化过程的脱氮工艺，在低浓度亚硝酸盐50 mg N/L的反应器中实现接近400 mg N/L/d的脱氮速率，而在高浓度亚硝酸盐1000 mg N/L的反应器中脱氮速率接近997 mg N/L/d；发现了NC10细菌在高低浓度条件下在“种”水平上出现生态位的分化。.构建了基于硝酸盐型厌氧甲烷氧化过程的脱氮工艺，在进水硝酸盐浓度1000 mg N/L运行条件下MBfR可实现1013 mg N/L/d的硝酸盐还原速率；发现了该体系内存在NO2-诱导ANME-2d古菌催化发生硝酸盐异化还原为铵过程（DNRA）；并解析了AOM耦合硝酸盐和硫酸盐同步还原过程的脱氮性能及其驱动碳-氮-硫转化的关键过程。