Research on Control Strategy of Dissolved Oxygen in Aerobic Wastewater Treatment Process

摘要

Aerobic biological wastewater treatment processes are difficult to be controlled because of their complex and nonlinear behavior, however, the control of the dissolved oxygen (DO) level in the reactors plays an important role in the operation of the facility, which affects the activity of activated sludge. A mathematical model of aeration system is established with the actual pulp and paper wastewater aerobic biological treatment process in Shandong as the background. Three control strategies for DO are designed. MATLAB simulation was carried out to compare the PID control, fuzzy control and fuzzy PID control of the step response. The robustness analysis of the three control systems is also researched. Conclusion is that the performance of Fuzzy PID control is the best.