低渗煤层机械造穴增透强化瓦斯抽采钻孔工艺参数研究设计OA

Enhancing permeability and strengthening gas extraction in low-permeability coal seams is one of the important measures to improve the effectiveness of coal seam gas extraction,which can effectively solve the problem of coal seam gas control.Taking the No.3505 mining face of Huo'erxinhe Coal Mine in Shanxi Province as the research object,in response to its mechanical cavitation technolo-gy for enhancing permeability and strengthening gas extraction,the mechanism of coal seam permeability enhancement under different occurrence parameter conditions was revealed.The optimization of mechanical cavitation parameters,drilling structure design and lay-out,and optimization of drilling process parameters were carried out.The drilling structure parameters and layout suitable for under-ground coal seam gas drainage in Huo'erxinhe Coal Mine were designed,and the construction process of mechanical hole making and enhancement was optimized.The airbag type"three blockages and two injections"continuous high-quality sealing technology was pro-posed,and the overall layout optimization of mechanical cavitation and enhancement gas drainage drilling holes was completed.Research has shown that when the length of mechanical cavitation holes is 1.5 meters and the spacing between holes is 3 meters,the pure gas ex-traction and gas concentration of a single hole are both increased by 80％.The research provides scientific basis and practical guidance for improving the efficiency and effectiveness of gas extraction from low-permeability coal seams in the mine,shortening the half-life of gas extraction boreholes,and other aspects.