Study On Simulation Of Wet Lime Flue Gas Desulfurization System For 660MW Units

This paper focuses on the wet lime flue gas desulphurization Systems of power plants which are widely used in China, limestone/gypsum wet flue gas desulphurization system for two 660MW units of a power plant is taken as the research object, the mathematic model has been developed and simulation analysis has been done.The significance of gas desulphurization project for power plant is presented firstly, then, the mechanism of wet limestone/gypsum desulphurization system is discussed, the mechanics flow and equipments of wet limestone/gypsum desulphurization system are introduced in detail. Based on the model of reactivity mechanism, according the research achievements of various chemical reaction, mass transfer, heat exchange, flow in the desulphurization technology, a dynamic simulation model of wet flue gas desulphurization has been developed using the idea of module. The model includes chemical reaction model,reactor model of spray tower and Oxidation tank,heat exchanger model,the conservation laws of mass-energy model. The main physical and chemical steps can be described, such as absorption of SO₂ and CO₂, dissolution of limestone, oxidation of sulfite and crystallization of gypsum, e.g.Based on static experiments, the impacts on efficiency of desulphurization from gas flow,concentration of SO₂,L/G and PH were discussed, and the Strategies for optimization in the step of operation were made; Based on the dynamic experiments, the impacts on efficiency of desulphurization and temperature parameters from gas flow,quantity of circular serous,partial pressure of SO₂,heat transfer area or heat exchanger,smoke density, e.g. According the coherence of the simulation results of static experiments,the dynamic experiments and other correlative datum, the correct of the model is proved from the verification on the precision and rationality of model.The simulation research on the limestone/gypsum wet flue gas desulphurization system in this paper can provide reference and consultation for the operating workers and developing the simulation training system.