Influence of coal particles on methane/air mixture ignition in a heated environment
Influence of coal particles on methane/air mixture ignition in a heated environment
复制标题
加热环境下煤颗粒对甲烷/空气混合物点火的影响
DOI：
10.1016/j.jlp.2012.09.012
复制
发表时间：
2013-01-01
影响因子：
3.5
通讯作者：
Yuan Chun-miao
中科院分区：
文献类型：
--
作者：
Li Gang;Li Chang;Yuan Chun-miao
煤尘发光的温度通常比甲烷/空气混合物的自燃温度(AIT)低得多，因此需要更好地理解在有煤粒存在的高温环境中甲烷/空气的点火。利用卧管式燃烧装置，研究了褐煤、两种烟煤和无烟煤对甲烷/空气燃烧特性的影响。对于所测试的四个煤样，煤颗粒的存在显著降低了甲烷/空气混合物在高温环境中着火的最低温度。直径为12 mm的1号烟煤将着火温度从595℃降低到500℃，认为是煤粒加热后释放的低AIT挥发分预燃点燃了甲烷/空气混合物。挥发分、硫含量和堆积的煤颗粒的大孔隙率都有利于甲烷/空气混合气在高温环境下的着火，而含水率和小颗粒尺寸则会降低着火。对于无烟煤，除了直径12 mm的样品外，当加热环境的温度低于甲烷的Ait(595℃)时，没有发生着火。无烟煤不容易点燃甲烷/空气混合物，其着火机理与燃烧的香烟有些相似。(C)2012爱思唯尔有限公司。保留所有权利。
The temperature at which coal dust glows is normally much lower than the auto-ignition temperature (AIT) of methane/air mixtures, and thus a better understanding is needed regarding methane/air ignition in a heated environment in the presence of coal particles. A horizontal tube apparatus was used to test the effect of brown coal and two kinds of bituminous and anthracite on methane/air combustibility. For the four coal samples tested, the presence of coal particles significantly reduced the minimum temperature for ignition of methane/air mixtures in a heated environment. No. 1 bituminous coal with 12 mm diameter decreased the ignition temperature value from 595 to 500 degrees C. It is thought that pre-ignition of low-AIT volatiles emitted from the heated coal particles ignited the methane/air mixtures. Volatiles, sulfur content, and large porosity of piled coal particles all enhanced ignition of methane/air mixtures in a hot environment, while water content and small particle size reduced ignition. For anthracite, no ignition occurred when temperatures of the heated environment were lower than the AIT of methane (595 C), except for the 12-mm-diameter sample. Anthracite did not readily ignite methane/air mixtures and the ignition mechanism was somewhat similar to that of a burning cigarette. (C) 2012 Elsevier Ltd. All rights reserved.