Gas Migration Law And Stereo Gas Drainage Technology Of Coal Seam With Soft And Low Permeability Under The Effect Of Mining

By use of the experimental study, theoretical analysis, numerical simulationmethod, and combining with field practice, safety mining key technology of the singlecoal seam gas with soft and low permeability characteristics are carried out, which takethe No.3coal mine seam of Yuwu coal mine as study object. First, the gas occurrencelaw and its influence factors of the No.3coal mine seam in Yuwu coal mine areanalyzed and grasped, and based on the above analysis we investigate into the mainreason of dynamic disaster containing gas. By using numerical simulation andnumerical simulation, the influence of buried depth on the stress and displacementdistribution of coal mine stope are investigated and grasped; the development height ofstope three zones with soft and low permeability characteristics are analyzedquantitatively and qualitatively, and the evolution law of the mining-induced fracturesfield and the seepage field are investigated and grasped. And the "Stereo Gas DrainageSystem” are established, which is baesd on the gas drainage of coal seam and combinedwith the horizontal multilateral drainage well and the kilometer rig drainage method.Finally, we investigated into the effect of "Stereo Gas Drainage System” gas drainage,and evaluated the gas prevention and control technology of the single coal seam withsoft and low permeability characteristics.