Gas Occurrence Regularity And Control Factors Of15~#Coal In Yangquan Wu Mine

Through studies such as observation, sampling, combined with variousexperiments, coal characteristics and gas occurrence regularity and control factors of15#coal in Yangquan Wu Mine are studied. Coal characteristics of15#coal arestudied by SEM, mercury injection and gas adsorption isotherm test et al. Theexperiments analysis results show that, pore of the15#coal are development and theyare mainly transition pore, accounted for about50%. The experiments analysis resultsof gas adsorption isotherm test show that, adsorptive gas content of15#coal isbetween33-35cm3/g, its adsorptive capacity of gas is strong.The performance of thegas occurrence regularity of Yangquan Wu Mine is that gas content and gas pressuredistribute with the trend of "west high and east low". Gas emission amount are mainlyfrom the country rock, only a small amount are from15#coal seam.Research shows that, geological controlling factors of15#coal seam gasoccurrence mainly include geological structure, coal seam depth, roof and floorlithology combination of coal seam and pore characteristics of coal, coal quality andcharacteristics of15#coal et al, the buried depth of coal seam is the main controllingfactor. In the aspect of structure, collapse column and small faults are developmentalin the Wu Mine, gas content in the structure is mainly affected by them. Mudstone orsandy mudstone caprock of collapse column are conducive to the occurrence of gas,sandstone or exposed on the surface caprock are beneficial to gas’ escaping. Smallfaults usually develop into intensive belt, they are usually the fault sealing, it isbeneficial to gas enrichment; In aspects of coal seam depth and roof and floorlithology, the correlation coefficient of gas content and buried depth of coal seam is0.9778, the correlation coefficient of gas content and roof and floor lithology arerespectively0.7556,0.9203; In the aspect of coal quality,15#coal are mainlyanthracite, gas volume generated by anthracite coal are large, and adsorption capacityof anthracite on gas is also large, it is beneficial to gas occurrence; In the aspect ofcharacteristics of15#coal seam, porosity of15#coal of Wu Mine are mailytransition pore, they increase the surface area of coal, enhance the capacity ofcoal adsorbed gas, it is beneficial to gas occurrence.According to the distribution of gas unusual emission points in the Wu Minemining area, the gas outburst occurs easily in those conditions that geologicalstructures are complex, coal seam depth is deep, gas pressure and gas content are high,the prevention suggestions of coal and gas outburst are summarized.