文摘
Soft sensing models of the desulfurization process are developed in a circulating fluidized bed (CFB) boiler that can capture sulfur dioxide (SO<sub>2sub>) with the limestone sorbent in the furnace. First, calcining utilization of CaCO<sub>3sub> and sulfating utilization of CaO are proposed by mechanism analysis of the theoretical air and flue gas, and the online prediction method is achieved by using an adaptive-tree-structure-based fuzzy inference system (ATSFIS). Second, condition monitoring models of active CaCO<sub>3sub>, active CaO, and soft sensing model of SO<sub>2sub> emissions are studied by using the experimental data of a CFB boiler in China, which can monitor the storage and condition of the limestone in the furnace and predict SO<sub>2sub> emissions. Finally, a nonlinear proportional–integral–derivative (PID) control system based on the above models is designed to control the feed rate of limestone for the reduction of SO<sub>2sub> emissions. The simulation results show that the soft sensing models are consistent with the mechanism test results and can accurately predict SO<sub>2sub> emissions. The control system of limestone is also proven to be effective.