Parameter Optimization On In-furnace Desulfurization Of Circulating Fluidized Bed And Optimization Of Control System

This paper took300MW CFB unit as platform,in-furnace desulfurization system as research object,established multi-objective parameters mathematical model according to main factors which impact in-furnace desulfurization after analyzing the process characteristics and influencing factors of in-furnace desulfurization. The model took consumption of limestone powder and total power consumption of desulfurization system as the objective functions, with parameters such as desulfurization efficiency,Ca/S moore ratio,bed temperature,SO2emission load,etc as constraint condition. Through the optimization and solution to parameters model,obtained a set of parameter solutions which not only met model constraint conditions but minimize the objective functions. In addition,this paper also proposed optimization and improvement scheme according to the shortage of control system.This paper firstly analyzed the influencing factors affecting the in-furnace desulfurization,ascertained that Ca/S moore ratio and bed temperature were two most influential factors to in-furnace desulfurization efficiency,meanwhile,these two factors were also parameters which could be adjusted at any time through changing coal quantity and limestone powder transport value of boiler during the period of unit operation. According to the economy principle of desulfurization system operation and the stability principle meanwhile limited Ca/S moore ratio and bed temperature which were viewed as constraint conditions after collecting data from desulfurization system of Shanxi certain coal gangue power plant. According to current pollutants emission standard and developmental level of desulfurization technology,took SO2emission load and desulfurization efficiency as constraint conditions of parameters model. Limestone powder consumption and the additional power consumption produced during the period of desulfurization system operation which affected desulfurization cost were also taken as objective functions,then calculated parameters solution which not only met constraint conditions but minimized objective functions after optimizing parameters.In addition,this paper also carried out optimization design according to shortages of the original desulfurization system. The original existed two obvious shortages including manual control and indeterminacy on whether pipeline clogged or not,so improved the original control system:export SO2emission load was took as the feedback signal so as to control the speed of feeding machine,and the pipelines pressure values were took as logical judgment signal to control the switch on start or stop of feeding machine. The system after improving overcomed the original shortages of the system and realized the better running performances.