Control Strategy Optimization for Electrostatic Precipitator System of Coal-Fired Power Plant Integrated With the Waste Heat Recovery System During Load Cycling Dynamic Processes

Abstract Coal-fired power plants will undertake more and more peak shaving and frequency regulation tasks to accommodate high penetration of fluctuating renewables. As a result, they often operate in load cycling dynamic processes, and the emissions of particulate matter (PM) are unavoidably affected by operation mode. Electrostatic precipitator (ESP) is widely applied in coal-fired power plants for collecting PM from flue gas, and the wet flue gas desulfurization (WFGD) system also removes PM while achieving efficient desulfurization. Because the flue gas temperature is an important factor affecting the PM removal efficiency, the regulation of the waste heat recovery system integrated within coal-fired power plants, which will influence the temperature of flue gas to ESP, will affect the operation of ESP. To achieve efficient PM removal, the dynamic characteristics and control strategies for the electrostatic precipitator system during load cycling dynamic processes should be further studied. In this study, the dynamic model of ESP was developed based on the Deutsch’s model, and the dynamic model of PM removal in WFGD system was developed with neural networks. These models were coupled with the dynamic model of a coal-fired power plant integrated with the waste heat recovery system. Then, changes in PM emissions were dynamically simulated during the load cycling processes. Dynamic characteristics of PM emissions influenced by the waste heat recovery system and WFGD system during the transient processes were obtained. Furthermore, an optimization control strategy for the electrostatic precipitator system was proposed based on the dynamic characteristics of PM emissions. When the proposed control strategy was adopted, the transient overshoot of PM emissions during the loading up processes could be avoided, and the power consumption of electrostatic precipitator system could be reduced considerably during the loading down processes.