综放工作面采空区高位定向钻孔抽采效果影响因素分析

为了分析采空区高位定向钻孔设计抽采参数对抽采效果的影响，运用统计方法研究了矿井53个高位定向钻孔的布置参数和抽采数据，确定了合理的钻孔布置层位和平距。以王家岭煤矿12311为试验工作面，试验了不同抽采负压和钻孔孔径下高位定向钻孔的抽采效果，综合判定了高位定向钻孔的最佳抽采负压和合理钻孔孔径，并对高位定向钻孔设计和抽采参数进行了优化，对优化后的钻场抽采效果进行了试验和分析。结果表明：高位定向抽采钻孔的合理布置层位为25～45m，平距为20～60m，最佳抽采负压为22.7kPa，最优孔径为133mm，优化后瓦斯抽采率提高15.5%，有效降低了回风流瓦斯浓度。

Analysis of Influencing Factors of High Level Directional Drilling in Caving Face Goaf

In order to analyze the influence of design parameters of high directional drilling on the extraction effect of goaf, the layout parameters and extraction data of 53 high directional drilling in mine were compared by statistical method, the reasonable layout horizon and spacing of drilling were determined; taking 12311 as test working face, the pumping effect of high directional drilling under different negative pressure of pumping and borehole aperture is tested, the optimum negative pressure and reasonable bore diameter of high directional drilling are determined; the design of high level directional drilling and extraction parameters are optimized, and the extraction effect of optimized drilling field is tested and analyzed. The results show that the reasonable decorate horizon of high directional drilling extraction of 25 m ~ 45 m, horizontal distance is 20m~ 60 m, the best extraction negative pressure of 22.7 Kpa, the optimal pore size for 133 mm, the gas extraction rate increased by 15.5% after optimization, effectively reduce the return current gas concentration.