微气泡曝气生物流化床反应器SNAD过程脱氮性能研究

Performance Study of Nitrogen Removal in Simultaneous Partial Nitrification, ANAMMOX and Denitrification(SNAD) Process in a Microbubble-Aerated Fluidized Biofilm Reactor

运行微气泡曝气生物流化床反应器(MAFBR),研究了不同运行策略下同步短程硝化-厌氧氨氧化-反硝化(SNAD)过程实现及生物脱氮性能。结果表明,MAFBR反应器采用高碳氮比(C/N)启动并逐渐降低C/N的运行策略时,生物脱氮过程为同步硝化-反硝化,硝化过程效率较低且为生物脱氮的限制因素,生物脱氮性能不理想。MAFBR反应器采用低C/N启动并控制适宜溶解氧(DO)浓度的运行策略时,生物脱氮过程由同步硝化-反硝化逐渐转变为SNAD过程,从而实现高效生物脱氮性能。MAFBR反应器可在C/N为1、DO平均质量浓度为1.29 mg/L条件下实现SNAD过程,其氨氮平均去除率和平均去除负荷可达到69.87%和0.31 kg/(m^3·d),总氮(TN)平均去除率和平均去除负荷可达到63.93%和0.29 kg/(m^3·d),厌氧氨氧化对TN去除的平均贡献率可达到52.89%以上。

A microbubble-aerated fluidized biofilm reactor（MAFBR） was operated in different operation strategies to realize simultaneous partial nitrification, ANAMMOX and denitrification（SNAD） process and its performance of nitrogen removal was investigated. The results indicated that the simultaneous nitrification and denitrification（SND） process was responsible for nitrogen removal in MAFBR, when one operation strategy as start-up at high ratio of carbon to nitrogen（C/N） and then reducing C/N gradually was applied, and the nitrification process was inefficient as the limiting factor for nitrogen removal, resulting in inefficient performance of biological nitrogen removal. When another operation strategy as start-up at low C/N and controlling suitable dissolved oxygen（DO） concentration was applied in MAFBR, the initial SND process for nitrogen removal converted gradually to SNAD process, which contributed to high performance of biological nitrogen removal. The SNAD process could be achieved in MAFBR at a C/N of 1 and an average DO concentration of 1.29 mg/L. In this case, the average removal efficiency and loading rate removed of ammonia nitrogen reached to69.87% and 0.31 kg/（m^3·d）, respectively. The average removal efficiency and loading rate removed of total nitrogen（TN） reached to 63.93% and 0.29 kg/（m^3·d）, respectively. The average contribution percentage of ANAMMOX process for TN removal was higher than 52.89%.