Research on Gas Comprehensive Controlling Mode in Fully Mechanized Caving Face

The mining technique was fully mechanized in a working face of Kailuan Group, the mining intensity was big, and the gas emission quantity was large. Based on this, the gas controlling mode of the working face was put forward, and on the basis of "U+L" type ventilation, one cutting hole and dip high-level gas drainage borehole were added, the measures were taken to adjust the ventilation quantity of return airway and gas drainage gateway. Then the gas migration law in goaf was studied under the gas controlling mode by using numerical simulation, and the engineering application was done in site. The results showed that the air flow containing gas was induced into the gas drainage gateway and gas drainage borehole, and the gas influx into upper corner in the deep of goaf was stopped, which largely reduced the gas concentration of goaf inside and upper corner of working face, and solved the problem of local gas accumulation in upper corner.