Anaerobic-Anoxic-Oxic (AAO) process is widely used in municipal wastewater treatment plants because of its simple structure, rich experience in engineering design, easy operation control and simultaneous nitrogen and phosphorus removal. The energy consumed in the aeration process occupies more than 50% of the total energy consumption of the sewage treatment plant, and reducing aeration is one of the major ways to reduce energy consumption. With the nitrification effect, the sewage treatment equipment controlled the dissolved oxygen (do) concentration in the aeration tank to 2 mg/L or more. The result shows that even nitrification can achieve complete nitrification. In a low oxygen state, the sewage treatment plant is reduced in energy consumption The degradation of pollutants in AAO process under different DO concentration was studied in a pilot-scale test. At the same time, the effects of temperature and carbon source on nitrogen removal in the system at low DO concentration were investigated, and the microflora structure was analyzed, in order to provide a reliable theoretical basis for the actual wastewater treatment plant to achieve stable and efficient nitrification at low DO concentration and save energy consumption.

厌氧-缺氧-氧化（AAO）工艺由于其结构简单，丰富的工程设计经验，易于操作的控制以及同时去除氮和磷的优点而广泛用于市政废水处理厂。曝气过程中消耗的能量占污水处理厂总能耗的50％以上，减少曝气是减少能耗的主要方法之一。利用硝化作用，污水处理设备将曝气池中的溶解氧（do）浓度控制在2 mg / L或更高。结果表明，即使硝化也可以实现完全硝化。在低氧状态下 通过中试研究，研究了在不同溶解氧浓度下AAO工艺中污染物的降解。同时，研究了温度和碳源对低溶解氧浓度下系统脱氮的影响，并分析了菌群结构，为实际废水处理厂实现稳定和稳定提供了可靠的理论依据。在低溶解氧浓度下进行高效硝化，并节省能源消耗。