CeO_2及其复合催化剂对煤粉燃烧效率的影响

Effect of CeO_2 and Its Composite Catalyst on Combustion of Pulverized Coal

利用热重分析法研究了稀土氧化物CeO2和其复合催化剂对煤粉燃烧特性的影响。研究了稀土氧化物及其复合催化剂的添加量、配比对煤粉燃烧特性的影响。结果表明:CeO2可以促进烟煤挥发分析出和燃烧,改善其燃烧性能,CeO2添加质量分数为4%时其催化效果最为显著;不同催化剂对无烟煤燃烧的催化效果各异,MnO2有利于挥发分析出,而CeO2促进了残碳的燃烧,其催化作用不同于烟煤;Ce-Fe-Mn系复合催化剂催化效果优于单组分催化剂,其中CeFeMn(3∶1∶1)的催化效果最佳。利用Coats-Redfern动力学模型分析了煤粉燃烧活化能、指前因子等动力学参数,添加CeFeMn(3∶1∶1)的煤粉反应速率常数较大,催化效果显著。

The effect of CeO2 and its composite catalyst on combustion characteristics of pulverized coal was investigated by thermogravimetric analysis. The experiments of different catalyst additive amount and components were conducted from room temperature to 900 ℃ in air. The results show that CeO2 can promote precipitation and combustion of volatiles and combustion characteristics of bituminous varied in different additive amount of CeO2. The combustion characteristics of bituminous with 4% CeO2 are improved obviously. Different catalysts can play different roles in combustion of anthracite. MnO2 promotes combustion of volatiles and CeO2 performs well in residue carbon combustion. Ce-Fe-Mn series composite catalyst shows better performance than the single one and the composite catalyst CeFeMn（3 ： 1 ： 1） performed best. Kinetic parameters were calculated by Coats-Redfern model. The value of reaction rate constant of pulverized coal with CeFeMn（3 ： 1 ： 1） is higher than others.