Hybrid Modeling and Operating Optimization Method of Oxidation Process of Wet Flue Gas Desulfurization (WFGD) System

Wet flue gas desulfurization systems (WFGD) are the most popular method to remove the SO2 from the flue gas in China's power plants. Most WFGD systems contain an oxidation subsystem, which is one of the most important subsystems. In this paper, a hybrid modeling and operating optimization method of oxidation process of WFGD system is proposed, verified and applied on the WFGD system of a typical 1000 MW unit. The influence of important parameters such as the diameter of droplets or bubbles, the liquidgas ratio or the gas-gas ratio (the ratio of between oxidized air flow rate and flue gas flow rate) and the height of the natural oxidation zone or the slurry level on natural oxidation rate and forced oxidation rate are further explored. The application results show that the above method can significantly reduce the operating energy consumption of the oxidation fan by more than 25 %. Furthermore, field tests are also carried out on the WFGD systems of 130 t/h and 220 t/h circulating fluidized bed (CFB) units. The energy consumption can be reduced by 30.6 % and 37.5 %, respectively. The results will be helpful to reduce the auxiliary power consumption and additional CO2 emission of WFGD.(c) 2022 Institution of Chemical Engineers. Published by Elsevier Ltd. All rights reserved.