A/O脱氮工艺实时控制对策的试验研究

以人工合成废水为研究对象,系统研究了提高A/O(anoxic/oxic)工艺氨氮和硝酸氮去除效率的实时控制对策.氨氮控制的本质是通过控制DO设定值和好氧区体积大小使出水氨氮浓度达标排放.硝酸氮控制的本质在于高效利用缺氧区反硝化潜力,为此建立了以调节内循环回流量或(和)外碳源投加量维持缺氧区末端硝酸氮浓度处于设定值的实时控制对策.系统控制采用两级结构,高水平监控层用来选择低水平执行层的设定值,而低水平执行层对DO值、好氧区体积、内循环回流量和外碳源投加量进行直接控制,试验表明上述控制对策可以显著提高系统脱氮效率,降低出水氨氮和硝酸氮浓度,并最大程度节约运行费用.

Experiment Study on Real-Time Controlling Rules of A/O Nitrogen Removal Process

The aim of this work is operational optimization of an A/O process in the lab plant with synthetic wastewater for improving nitrogen removal efficiency. Ammonia control aims at maintaining the required concentration of ammonia in the effluent by manipulating the dissolved oxygen (DO) set point and aeration volumes. Nitrate control aims at the optimal use of the denitrification potential at any moment by continuously adjusting the internal recirculation flow or (and) external carbon addition flow in order to maintain a desired nitrate set point in the anoxic zone. The control strategies have been based on a hierarchical structure where a high level or supervisory control selects the set point of the low level or conventional controllers. Results indicated that it was possible to increase nitrogen removal efficiency, improve the effluent water quality, save energy, and reduce operating costs.