Establishment and application of the stereo drainage model for high gas working face of short distance seam group

Abstract：According to the geological and mining conditions on high gas working face of short distance seam group, es- tablished a model for the gas stereo drainage roadway during the roadway excavation and mining at high gas working face. By pre-digging the inboard floor low-position roadway or the inboard roof high-position roadway, and arranging the drilling through seam or the drill field for gas stereo drainage during the roadway excavation;digging inboard high-posi- tion roadway drilling through seam and the crossheading bedding drilling for pre-drainage was done during the working face mining. Based on the stereo drainage model, combined with the geological conditions, the surrounding rock condi- tions of roadway and the exploitation of environmental and the technical conditions, through the field experiments and applications, some parameters are got, like that the vertical and inboard distance of the gas drainage roadway is 15 m,the drill field distance of high-position roadway is 100 m and the crossheading bedding drilling dis- tance is 2 m. And the gas pre-drainage of protective seams is carried out. By the gas stereo drainage, it reaches the re- quirement of gas drainage between roadway excavations and working face mining, so the new technology can be used to control the concentration of gas, achieve the mining safety and release the gas of the upper seams.