煤岩混合型粉尘云最低着火温度试验研究

Experimental study on the minimalist ignition temperature of the mixed coal and rock dust cloud

为研究半煤岩巷道中岩粉质量分数和煤的挥发分与煤岩混合型粉尘云最低着火温度的关系,选取挥发分差异较大的5种煤样以相同比例配制煤岩混合型粉尘,利用粉尘云最小点火温度测定仪进行煤岩混合型粉尘试验。结果表明,当煤岩混合型粉尘中岩粉质量分数低于40%时,岩粉的混合会导致混合型粉尘云最低着火温度发生小幅度波动;当岩粉质量分数高于40%时,煤岩混合型粉尘最低着火温度会随岩粉质量分数的增加而大幅度升高;挥发分质量分数越小的煤粉,其混合型粉尘云最低着火温度越容易受岩粉质量分数的影响。

The purpose of this paper is to explore the relations among such factors,as the rock dust content in semi coal rock tunnel,the volatile matter in the coal and the minimalist ignition temperature of the mixed dust cloud,for it is a crucial indicator to control the dust explosion to be caused by the minimalist ignition temperature of the coal dust cloud. What is more,it is necessary to do lots of industrial analysis experiments to disclose the aforementioned relations. It is just for this purpose that we have prepared five coal samples with the distinctive volatile features,trying to make the mixed dust samples of the rock dust content at different percentages（ e. g. 20%,30%,40%,50%,60%,70%,and 80%） by using a minimalist ignition temperature testing and measuring instrument. Thus,it would be possible for us to arrive at the following conclusions through data mining,curve fitting and diagram analysis. First of all,it can be deduced that,when the rock dust content remains at a percentage less than40%,it would be possible to reduce the minimum ignition temperature of the mixed dust cloud in case it be mixed with the rock powder. In other words,less than 40% of coal powder would be enough to prohibit or prevent the coal powder from being exploded. On the other hand,when the rock powder content is over40%,it would dramatically increase the minimum ignition temperature of the mixed dust to lead to likely explosion of the rock powder. In such a status-in-situ,the rock powder can effectively prevent the coal powder from being ignited. Thus,the experiment results can further imply that there must be existing a linear relationship between the reduction of the minimum ignition temperature and the volatile content of the mixed rock powder. Or,more specifically speaking,the less volatile matter the coal powder contains,the more remarkably the minimum ignition temperature can be affected by the content of the rock dust. Thus,it is concluded that the paper has provided more accurate data and information ground for preventing from the coal dust explosion and the temperature minimalist limit for the electrical device and applicance.