Study On Gas Prevention And Control Technology At Fully Mechanized Caving Face Of Liujia Coal Mine

According to the phenomenon of gas abnormal emission and exceeding the limit during the period of tunneling and production at Liujia coal mine WⅡN16-7 fully mechanized caving face, use direct method to test the gas content of self coal seam 6-7 and adjacent coal seam 6-8, 0.73m3/t and 0.62m3/t, respectively. Apply different-source prediction to predict the gas emission, the gas emission of goaf is 1.14m3/t, accounting for approximately 65% of total gas emission. On the basis of analyzing the gas emission characteristics, through the ground atmospheric pressure and underground gas concentration measurement, the reason is due to the changes of ground atmospheric pressure, and the output of working face and different working process. Adopt borehole gas drainage in upper goaf and the coal goaf buried tube drainage combined control measures, increase nitrogen injection measures based on gas drainage, realize controlling gas and fire prevention parallel technical measures, use T-junction and piston to install tubes for the first time, ensure the safety of normal production.