煤粉细度对燃烧特性影响的实验研究

对冷水江和斗笠山两种煤粉,采用热天平进行了热重分析实验,分析了煤粉样在不同细度下的着火特性、燃烧特性、燃尽性能及动力学参数,给出了反映煤粉燃尽性能的综合判别指数Hj并进行了对比.结果表明:在相同的升温速度下,随着煤粉粒径的减小,挥发分析出量及DTG峰值增大,出现最大燃烧速率的时间提前;煤粉粒径减小,活化能降低,着火温度降低,着火提前,煤粉的燃烧特性也随之变好.

Experimental Investigation of the Influence of Coal Powder Fineness on Combustion Characteristics

Thermogravimetric tests of pulverized Lengshuijiang and Doulishan coal have been carried out.Ignition and combustion characteristics,burnt-out performance and dynamic parameters of coal samples of different fineness have been analyzed.A comprehensive discrimination index H_j,which may reflect the coal powder's burnt-out performance,is being recommended with comparisons performed.Results show that,under the same heating-up rate,the amount of released volatile matter and the DTG peak value,both increase with reducing coal particle size,which also causes the maximal combustion rate to appear earlier.On the other hand,decreasing coal particle size causes a reduction of activation energy and ignition temperature with an earlier occurrence of ignition;thus effecting an improvement of combustion characteristics.