不同粒径煤粉煤质变化及燃烧特性研究

摘要

采用哈氏可磨测试仪对阳泉无烟煤、印尼褐煤进行研磨,测出其哈氏可磨性指数HGI,同时用马尔文激光细度仪对可磨仪研磨后的煤样进行细度测量.利用振筛机对研磨后的煤样进行筛分,区分出4种不同粒径的煤粉,然后用工业分析仪测出其工业分析成分,研究其工业分析成分之间的区别;采用热重分析仪进行燃烧试验,研究粒径及工业分析成分变化对燃烧特性的影响.结果表明:研磨后煤粉中的不同粒径煤粉在研磨过程中产生工业分析成分的偏离,影响煤粉的热解、着火、燃烧等特性;研磨后煤粉中的细粉相对粗粉增大了比表面积并改变了孔隙结构,对煤粉的着火、燃烧稳定性、燃烬性等都有积极的影响;由于两种煤种煤质的不同,导致其燃烧机理及燃烧特性的不同.%The HGI (Hardgrove Grindability Index) analyzer was used to mill the Yangzhou anthracite and Indonesian brown coal and to obtain the HGIs of the two coals. Malvern Mastersizer was used to measure the size of the milled coals. A screen shaker was used to screen the coal samples into pulverized coals of four different sizes. An industrial analyzer was used to obtain the proximate analysis, and studied the effect of coal size on the distribution of coal type. A TGA was used to conduct combustion experiments, and studied the effects of coal sizes and coal types on the com-bustion properties. The results show that the coal size can significantly influence the distribution of coal types, and the distribution of coal types can influence the pyrolysis, ignition and combustion properties. Meanwhile, decreases in coal size can increase the specific surface area and change the pore structures, which can positively affect the ignition, com-bustion stability and burnout properties for the coal. Moreover, differences in coal properties can result in different combustion performances and mechanisms.