Experimental Research On Minimum Ignition Temperature Influence Factors Of Coal And Rock Mixed Dust Cloud

The minimum ignition temperature of dust cloud is a crucial parameter in dust explosion.The purpose of this study is to explore the relations between factors,i.e.,the influence factors of the mixed dust cloud minimum ignition temperature,the industrial analysis parameters of coal and coal dust cloud minimum ignition temperature,rock dust content in semi coal rock tunnel and coal dust cloud minimum ignition temperature,plus water content and mixed dust cloud minimum ignition temperature.To investigate these relations,many industry analysis experiments have been conducted.This thesis selected 10 kinds of coal sample,which have a gap of industry analysis parameters.Using a minimum ignition temperature measuring instrument to test the dust cloud minimum ignition temperature of pure coal.Then,in the above,selected 5 coal samples with distinct volatile matters.Mixed dust samples with different percentage(20%,30%,40%,50%,60%,70%,and 80%)of rock dust content and test these mixed dust cloud minimum ignition temperature.By adding water to join in the mixed dust mass fraction is 5% ~ 35% of the water,then,test mixed dust cloud minimum ignition temperature.the experiment result s show that: The overall trend,there is a linear correlation between volatile matter of coal and the pure coal cloud minimum ignition temperature.But the inherent moisture and inherent ash in coal has less affected to pure coal cloud minimum ignition temperature.When the percentage of rock dust content is less than 40%,the mixing of rock powder will slightly reduce the minimum ignition temperature of mixed dust cloud.On the other hand,when the percentage of rock powder is higher than 40%,the minimum ignition temperature of mixed dust will increase dramatically with the percentage of rock powder.Moreover,the less volatile matter the coal dust has,the more significantly the minimum ignition temperature is influenced by the content of rock dust.More specifically,the increase of moisture content will make hybrid dust cloud a significant rise in the minimum ignition temperature.The less volatile matter the coal dust has,the more sensitive with Stone powder content and moisture content.