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Right under Oxyfuel CFB furnace heat transfer characteristics were studied and analyzed . Reference conventional air state heat transfer model , the establishment of circulating fluidized bed boiler at the oxyfuel combustion heat transfer model . At different oxygen concentrations ( eg 30 %, 50 %, 70 % oxygen concentration) , the analysis of the flue gas composition , particle size , flue gas temperature , porosity , gas concentration , and other parameters of the boiler furnace height internal gas-solid two phase flow , volatile release and combustion , combustion of coke , obtained under the conditions of various parameters on the oxygen circulating fluidized bed heat transfer parameters affect the curve . Combustion model combines equal density shrinking core model and Equal shrinking core model , introduced and coal ash layer resistance associated with the diffusion rate , the introduction of a common power coal reaction rate theory . And conventional air through the heat transfer calculation compared to the results validate the model . The main conclusions are: oxygen-rich conditions compared to air mode , flue gas composition on the heat transfer coefficient influential but little heat transfer characteristics change is not too obvious, conventional boiler may be through some relatively simple modification to meet the oxyfuel conditions . Select a 300MW CFB boiler unit for the study to study internal boiler heat transfer characteristics , the analysis of the results by the model discussed under oxyfuel CFB boiler design . Respectively 30%, 50 %, 70% three concentrations of the heating furnace and the heat absorption surface area ratio calculated ratio , compared to obtain the oxyfuel combustion furnace . Summed CFB boiler size , liquidity , and heat transfer characteristics with increasing oxygen concentration variation and conducted under oxyfuel furnace conceptual design .
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