循环流化床富氧燃烧下CaO碳酸化实验研究

Research on the carbonation of CaO in oxy-fuel fired circulating fluidized bed

利用热天平对富氧气氛下CaCO3煅烧产物碳酸化特性进行了实验研究,分析发现,温度是决定碳酸化反应速率快慢及最终转化率高低的关键因素,在一定的温度范围内,随着温度的升高,碳酸化反应速率加快,最终转化率提高。同时发现,CO2浓度增加可加快化学反应阶段速率,但最终转化率相差不大。对CaO活化能的计算,采用了分阶段计算。不同CO2浓度的活化能相差不大,而且产物层控制阶段的活化能都比化学反应控制阶段的活化能大很多。

The carbonation of CaO calcinated from analytical regent CaCO3 is studied in a thermo gravimetric analyzer and the reaction is in oxy-fuel condition. Experiment results show that temperrature is the key factor of carbonation reaction. Within a certain temperature range, higher temperature can accelerate the carbonation of CaO and increase the conversion ratio. It is also found that CO2 cncentration can accelerate the reaction as well, while the conversion ration remains almost the same. The activation energy of carbonation of CaO is calculated according to different stages and result shows that the activation energy doesn＇t differ a lot when the CO2 concentration changes. And the activation energy in product layer diffusion control regime is much larger than that in the chemical reaction control regime.