Expert system based dissolved oxygen control in APMP wastewater aerobic treatment process

Because of such characteristics as severe non-linearity, time-delay in wastewater aerobic treatment process of alkaline peroxide mechanical pulping (APMP), no satisfied control performance can be obtained for the control of dissolved oxygen (DO) consistency by conventional control technologies such as PID (Proportional Integral Derivative). A novel control method based on expert system (ES) is proposed in this paper. The basic idea is concluded as follows: A feedforward and feedback plus PID control scheme based on expert system for DO value control is employed, by which different control rules are made according to the derivative of DO values in different stages. This control strategy has been embedded into a wastewater aerobic treatment process control system running in China and resulted in notable profits.