低C/N比城市污水IFAS-OSA组合工艺强化脱氮及污泥减量机理与调控策略研究

传统生物脱氮采用硝化和反硝化技术，存在污泥产量大、曝气能耗高、碳源不足和脱氮效率低等问题。针对城市污水处理强化脱氮和污泥减量的技术需求，本项目拟开展低C/N比城市污水IFAS-OSA组合工艺强化脱氮及污泥减量机理与调控策略研究。通过生物膜富集厌氧氨氧化菌，强化反应器的厌氧氨氧化脱氮性能；通过缺氧/好氧环境交替、溶解氧控制和OSA的组合工况抑制NOB活性；通过生物膜和OSA工艺等措施强化污泥减量效果，减少厌氧池占地面积；探究缺氧/好氧格室布置方式、间歇曝气方式、水力停留时间、回流比和温度等影响因素对反应器脱氮性能和污泥减量的作用机制；通过对蛋白酶活性、α-葡萄糖苷酶活性、ATP含量和脱氢酶活性等指标分析，揭示工艺的污泥减量机理；分析微生物的种群特性、反应器脱氮性能和污泥减量之间的相互关系，确定工艺的优化调控策略，为低C/N比城市污水处理提供技术参考依据。

Traditional nitrification-denitrification process is commonly used to remove the nitrogen from wastewater, which has many drawbacks, such as massive sludge yield, high aeration energy consumption, extra carbon source addition and low nitrogen removal efficiency. In this study, the IFAS-OSA (integrated fixed-film activated sludge-oxic settling anaerobic) process will be used to improve the nitrogen removal performance and reduce sludge production. The mechanism and control strategy for treating low C/N (chemical oxygen demand/total nitrogen) ratio municipal wastewater will be explored. In order to enhance the anammox process, the biofilm will be used to enrich the anammox bacteria. Meanwhile, the alternate anoxic/aerobic condition, DO (dissolved oxygen) concentration control and OSA process will be integrated to suppress the NOB activity. Moreover, the biofilm and OSA process will be operated to enhance the sludge reduction performance and reduce the volume of anaerobic sludge retention tank. The impact of key parameters on the nitrogen removal performance and sludge reduction performance will be investigated, such as the anoxic/aerobic tank layout, intermittent aeration mode, hydraulic retention time, reflux ratio, temperature, etc. The sludge reduction mechanism will be revealed by analyzing the protease activity, α-glucosidase activity, ATP (adenosine triphosphate) concentration and dehydrogenase activity. The relationship among microbial population characteristics, nitrogen removal performance and sludge reduction performance will be analyzed. Finally, the optimal parameters and control strategy of the reactor will be determined, which will provide important guidance for low C/N ratio municipal wastewater treatment.