为给矿井本煤层瓦斯预抽钻孔间距设计提供依据,将煤层视为孔隙裂隙二重介质,综合考虑瓦斯的渗流与扩散解吸过程,建立了瓦斯流动方程,求出了满足预抽时间和煤层瓦斯预抽率要求的最大钻孔间距,作为本煤层瓦斯预抽钻孔的合理布置间距.在杜儿坪矿8号煤层工作面进行了应用研究,结果表明:随着钻孔间距的增加,同样时间内的煤层瓦斯预抽率呈减小趋势;在预抽时间为200 d,煤层瓦斯预抽率为30%的要求下,工作面采用5 m的钻孔间距是最为合理和经济的.%In order to provide the basis for the design of the gas pre-drainage berehole space in the mining seam, taking the mining seam as the double medium of the porous fractures, in comprehensive consideration of the gas penetration flow and diffusion desorption processing, a gas flow equation was established and the max space between the boreholes to meet the requirements of the pre-drainage time and the seam gas pre-drainage rate was calculated as for the rational pattern space for the gas pre-drainage boreholes in the mining seam. The applied study was conducted on the coal mining face in No. 8 seam of Du'er'ping Mine and the results showed that as the space between the boreholes increased, the seam gas pre-drainage rate would be in the reduction tendency at the same time. And within a pre-drainage time of 200 d, under the requirement of the seam gas pre-drainnge rate of 30％, the 5 m space between boreholes applied in the coal mining face would be most rational and economic.
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