瓦斯煤粉耦合体系着火实验研究

为研究煤矿井下瓦斯、煤粉、空气3成分体系的着火特性，在改进的粉尘云最低着火温度测试装置(G-G furnace)内，选取4种煤样进行瓦斯与煤粉耦合条件下的引燃实验研究。 实验结果表明：当有煤粉存在时，瓦斯-煤粉-空气3成分耦合体系的最低着火温度（MIT）均低于瓦斯、煤粉的最低着火温度，且煤粉粒径越小、煤粉挥发分越大，耦合体系的最低着火温度下降的越多。D50≈25 μm的1号煤样使得耦合体系的着火温度比瓦斯低340 ℃，比煤粉低110 ℃。说明煤矿井下电气设备按纯的甲烷气体进行防爆温度设计和选型，若不考虑煤粉的影响，具有引燃瓦斯-煤粉-空气3成分耦合体系的风险，需加以完善和改进。

Experimental study on the ignition of the coupling system of coal gas and coal dust

To analyze the ignition characteristics of gas，coal dust and air 3 component system，using the modified minimum ignition temperature of dust cloud test device(G-G furnace)，a set of experiments on the minimum ignition temperature of coal gas and coal dust coupled system was conducted in this study.The coal dust samples include brown coal，two types of bituminous coal and a type of anthracite coal.The results show that the minimum ignition temperature（MIT） of the coupling system is lower than that of coal gas and coal dust.Moreover，the higher the volatile matter and the finer the coal dust particles，the lower the MIT of the coupling system.For example，for the No.1 coal dust sample with D50≈25 μm，the MIT is 340 ℃ lower than that of coal gas and 110 ℃ lower than that of coal dust.The study demonstrates that it may not be safe enough to design the allowable temperature of the electrical equipment used in coal mine only based on the MIT of coal gas.This is because of the potential ignition risk due to the presence of coal gas coal dust coupling system.The actual technical requirements should be improved.