Abstract: Different chars have been prepared from Datong coal with the spouted bed reactor at four pyrolysis temperatures, 550, 650, 750 and 850℃. The influence of pyrolysis temperature on the combustion characteristics of different chars is studied using a thermo-gravimetric device. A new dimensionless combustion index Z has been proposed to describe the combustion behavior of coal and char. The higher the Z value, the better the combustion behavior. Under the condition of 2℃/min heating rate for example, the Z value of Datong raw coal is 0.41, that of Yangquan anthracite 0.12, and Z values of chars at four pyrolysis temperatures, 550, 650, 750 and 850℃, respectively are 0.39, 0.35, 0.31, 0.21. The combustion reactivity of different chars is lower than that of Datong raw coal, but higher than that of Yangquan anthracite. For different chars, with the increasing of pyrolysis temperature the Z decreases, the combustion behavior becomes worse, which agrees with the variation of ignition temperature and apparent combustion activation energy.

Key words: char, ignition temperature, combustion index, kinetic parameter

摘要： 利用喷动载流床模拟煤拔头工艺，在550, 650, 750和850℃温度下对大同烟煤进行热解得到拔头半焦，采用非等温热分析方法对原煤及拔头半焦的燃烧特性进行了研究. 由热分析实验数据归纳提出了表征煤和半焦着火、燃烧及燃烬性能的无量纲综合燃烧指数Z. Z值越大，煤样综合燃烧性能越佳. 结果显示，大同烟煤在2℃/min升温速率下Z值为0.41；4个热解温度(由低到高)下所得拔头半焦的Z值分别为0.39, 0.35, 0.31, 0.21，且拔头半焦的燃烧性能均低于原煤，但高于阳泉无烟煤，且随热解温度升高Z值降低，燃烧反应性降低. Z值与着火温度及表观燃烧活化能表现出的反应性一致.

关键词: 半焦, 着火温度, 燃烧指数, 动力学参数