Research On FGD Reforming Technologies Of The 2×135MW CFB Boiler Of Lingzhou Power Plant

With environmental pollution has become more and more severe. As a result, the nation is imposing an increasingly strict control over air quality. Coal-fired power plant emissions have always been the focus of environmental control. The latest "Emission standard of air pollutants for the thermal power plant" (GB13223-2011), which was formally implemented on Jan 1,2012, greatly improves the requirement on SO2 emission control, with the SO2 emission limits of coal-fired power plants reduced to 100mg/m3, while that for the coal-fired power plants in key areas is reduced to 5Omg/m3.Lingzhou power plant of Ningxia Ninglu coal limited liability company performs the SO2 emission standard in key areas. Though a furnace limestone injection desulfurization system is established for its 2×135MW CFB boiler, the plant can’t meet the lately enforced standard GB13223-2011. Facing that the plant will have to be forced to shut down for not being able to meet the standard, Lingzhou power plant plans to reconstruct using limestone-gypsum wet desulphurization.Combining the actual demand of Lingzhou plant CFB boiler flue gas desulfurization project, this paper mainly researches on the desulfurization process design scheme, the selection of basic parameters and the principle of material balance calculation of the CFB boiler limestone-gypsum wet desulphurization. The computational fluid dynamics (CFD) technique is used to conduct the numerical simulation study for the absorption zone of absorption tower and the gas-liquid flow field of mist eliminator and the corresponding optimization design measures are proposed. Through the simulation calculation and the debugging test to the whole process, the integration and optimization of materials and energy flow are completed and the optimal process and operating parameters are achieved. FGD system is reliable and stable, while the desulfurization efficiency, dust emission concentration, limestone consumption and other performance targets all meet or exceed the designing performance requirements after the desulfurization renovation project of Lingzhou plant is put into operation.The paper focus on the application of limestone-gypsum wet flue gas desulfurization technology on the 135MW thermal power CFB boiler flue gas desulphurization project to achieve the latest "thermal power plant air pollutant emission standards" requirements. The proposal of SO2 emission control technology and system optimization scheme of wet FGD system, as well as the application of the combining technology of furnace limestone injection desulfurization and limestone-gypsum wet flue gas desulfurization well meet the emission standard and ensure a high efficiency and low energy consumption operation, which have an important demonstration effect for CFB boiler flue gas desulphurization renovation.