济北矿区煤尘层最低着火温度变化规律分析

Variation law of minimum ignition temperature of coal dust layer in Jibei Mining Area

为了探究埋深、粒径对煤尘层最低着火温度的影响,选取济北矿区煤样,在对深部煤层物化性质研究的基础上,通过热板实验测得不同埋深、粒径的煤最低着火温度。结果表明:在实验温度范围内,煤尘层厚度为5mm,埋深增加,其挥发分含量上升,由33.65%增至38.9%,煤尘层最低着火温度从330℃降至270℃,煤尘层着火现象用肉眼可观测到。随煤样粒径不断减小,不同埋深煤样的煤尘层最低着火温度明显减小,在煤尘层同为5mm时,随煤样粒径由180μm逐渐减小到75μm,3种不同埋深煤样煤尘层最低着火温度分别减小了16%、19%、25%,差异显著。

In order to explore the influence of buried depth and particle size on the minimum ignition temperature of coal dust layer,coal samples from Jibei Mining Area are selected.Based on the physicochemical properties of deep coal seams,the minimum ignition temperature of coal with different depths and particle sizes is measured by hot plate experiments.The results show that in the experimental temperature range,the thickness of the coal dust layer is 5 mm,the buried depth increases,the volatile content increases from 33.65%to 38.9%,and the minimum ignition temperature of the coal dust layer decreases from330℃to 270℃.The phenomenon of layer fire can be observed with the naked eye.As particle size of the coal sample decreases continuously,the minimum ignition temperature of the coal dust layer of different buried coal samples is significantly reduced.When the coal dust layer is 5 mm,as the coal sample particle size decreases from 180μm to 75μm,the minimum ignition temperature of the coal dust layer of three different buried depths decreases by 16%,19%and 25%respectively,the difference is significant.