不同密度级别无烟煤粉催化燃烧研究

利用热重法研究了K₂CO₃对不同密度无烟煤煤粉燃烧特性和动力学的影响。结果表明:K₂CO₃能够改善煤粉的燃烧性能; 在K₂CO₃溶液最佳添加量浓度为 15%时, 低密度煤粉着火温度降低 56.7℃,中密度煤粉着火温度降低 30℃;随着K₂CO₃负载量的增加, 煤样的最大失重速率对应的温度先降低后升高, 但均低于原煤; 由于中密度煤粉矿物质含量高, K⁺离子含量低,在最佳催化剂含量下, K₂CO₃对低密度煤粉的催化作用优于对中密度煤粉的催化作用; K₂CO₃催化煤燃烧机理可用氧转移理论解释; K₂CO₃可减小体系表观活化能。

Catalytic Combustion of Anthracite Coal with Different Density Fractions

The effects of K₂CO₃ on combustion property and kinetics of different fraction coal samples were investigated with a non-isothermal thermogravimetry. The results show that K₂CO₃ can improve the combustibility of pulverized coal. When the optimum value of the K₂CO₃ loading is 15%, the ignition temperature of the lower density fraction decreases by 56.7 ℃ comparing with a medium density fraction decreasing by 30 ℃. The temperature of maximum rate decreases first and then increases with the load of K₂CO₃ increasing, but it is always lower than untreated coal. K₂CO₃ has more effect on coal sample with low density fraction than that with high density fraction under the best circumstance, because of high mineral content and low K⁺ iron in medium density fraction. Oxygen-transfer can explain the reason and K₂CO₃ reduce the apparent activated energy.