Effect Of Reducing Components And Additives On Desulfurization And Denitrification Processes In CFB Boiler Furnace

The circulating fluidized bed(CFB)boiler is a clean coal combustion equipment that can effectively reduce the emission of gas pollution because of its intense gas-solid mixture,appropriate furnace temperature,etc.By using calcium-based desulfurization agent and SNCRdenitration in CFB boiler can get high desulfurization and denitration efficiency.But with the environmental emission regulations are becoming more and more strict,it is a big challenge for the application of the existing technology of desulfurization and denitration.In this dissertation by using self-made equipment,the effect of reducing component/the kind and ratio of different additives/reaction temperature for desulfurization and denitration were researched.By using TGA-FTIR system and quartz tube furnace heating system,bituminous coal and CO were selected as reducing components to react with desulfurization products and the reaction product and result were analyzed and researched.Different experimental results showed the consistent conclusion,by increasing the ratio of reducing components inreactants the fraction of desulfurization decomposed and released S became higher.It was a negative influence during desulfurization process.In the sample mixed with bituminous coal and CaSO4,when the mass fraction of bituminous coal increased from 4.1%to 20.2%,the fraction of desulfurization decomposed and released Sincreased from 14.84%to 26.14%.On a SNCR denitration experimentalsystem,we focused on how to raise the efficiency of SNCR denitration under low load condition of CFB boiler.Several kinds of gas and liquid additives were selected to research the effect of additives on the SNCR denitration efficiency/ammonia escape/the emission of COand N20 which were air pollutions.All of the additives can widened the SNCR reaction temperature window to low temperature direction in different degrees.On this basis,CH4/C3H8/ethanol/NaCl/NaOH were selected as additives to investigate the effect on the SNCR denitration efficiency on a medium scale denitration experimental system.Only CH4 increased about 8%SNCR denitration efficiency when the addition ratio was 1.2 under 805?.The performance of the rest additives were not as good as CH4.