催化剂对煤粉燃烧特性的影响及动力学研究

采用热分析技术,研究了CaO、Fe2O3、MgO和MnO24种催化剂对精煤和瘦煤燃烧特性的影响,以及非等温燃烧条件下,催化剂对燃烧反应动力学参数的影响。研究表明:当加入量为1%时,4种催化剂都能降低精煤和瘦煤的初始燃烧温度,其中CaO对煤粉的催化助燃效果最为显著。同为过渡金属氧化物,当加入量小于2%时,MnO2降低两种煤粉初始燃烧温度的效果要好于Fe2O3;当加入量为2%时,MnO2降低两种煤粉初始燃烧温度的作用减弱,比Fe2O3的作用要差,加入瘦煤试样时,该现象尤为明显。4种催化剂都能降低精煤和瘦煤在第1反应阶段的活化能,其中CaO表现出的助燃效果最好;在第2反应阶段,CaO对精煤的催化燃烧作用最好,而4种催化剂对瘦煤的催化燃烧作用不明显。

Kinetic Analysis and Effect of Catalysts on Combustion Characteristics of Pulverized Coal

The effect of four catalysts,CaO,Fe2O3,MgO and MnO2 on non-isothermal combustion characteristics and dynamic parameters of clean coal and lean coal was investigated with thermal analyzer.The results show that when the content of catalysts is 1%,four catalysts can reduce the initial burning temperature of two coals and CaO is the most effective catalyst to accelerate coal combustion.As transition metal oxide,MnO2 shows an optimum effect on reducing the initial burning temperature of two coals than Fe2O3 when the content of catalysts is fewer than 2%,but this condition changes when the content of catalysts is 2% especially when the two catalysts are added in lean coal.Four catalysts can decrease activation energy of two coals and CaO increases combustion process best during reaction stage 1.CaO accelerates combustion process of clean coal for best results and four catalysts have no significant effect to accelerate combustion process of lean coal during reaction stage 2.