K2CO3/Al2O3固体吸附剂脱碳试验与数值模拟的比对分析OA

To promote the engineering application of the CO2 capture technology by K2CO3/Al2O3 solid adsorbents,the comparative study of experiment and simulation for the adsorption-regeneration cyclic decarburization system by K2CO3/Al2O3 solid adsorbents was conducted.Firstly,an experimental setup for the adsorption-regeneration cyclic decarburization system by K2CO3/Al2O3 solid adsorbents was established.Cold-state gas-solid flow experiments ensured excellent solid circulation in the setup.In the hot-state CO2 capture experiments,for a flue gas treatment capacity of 4.0m3/h,under operating conditions of a solid circulation rate of 30kg/h,adsorber bed height of 350mm,adsorption temperature of 333K,and regeneration temperature of 573K,the setup achieved approximately 80％CO2 capture efficiency over 20-hour continuous operation.Besides,the adsorbent maintained excellent decarburization capability despite the presence of wear.Secondly,to explore the multiphase reactive mechanism within the experimental system,three-dimensional numerical simulations were performed.The results showed that the CO2 mass fraction at the gas-solid separator outlet was 2％,corresponding to a CO2 capture efficiency of 80％.The dry-based CO2 mass fraction at the regenerator outlet reached 99％,meeting industrial requirements.At the inlet of the gas-solid separator,the mass fractions of K2CO3 and KHCO3 were 17.4％and 14.5％,respectively,while at the return pipe,the mass fractions of K2CO3 and KHCO3 were 29.9％and 0.1％,respectively,with the adsorbent conversion rate of 36.5％.Finally,by combining experimental and numerical methods,effects of fluidized bed parameters on CO2 capture efficiency were further analyzed.It was found that increasing the solid circulation rate,adsorber bed height,water vapor concentration,and regeneration temperature helped improve the CO2 capture efficiency.Keeping other parameters constant,when the solid circulation rate increased(10kg/h→30kg/h),the CO2 capture efficiency increased(69.3％→81.3％).When the adsorber bed height increased(250mm→450mm),the CO2 capture efficiency increased(68.2％→85.7％).When the water vapor concentration increased(8％→14％),the CO2 capture efficiency increased(66.0％→82.1％).When the regeneration temperature increased(473K→573K),the CO2 capture efficiency increased(63.1％→81.3％).Nevertheless,enhancing the cyclic decarburization performance by varying fluidized bed parameters was also influenced by comprehensive energy consumption.