穿层钻孔水力化卸压增透技术

低透气性煤层瓦斯抽采是我国矿井瓦斯治理的瓶颈所在。近年来水力射流技术在矿井石门揭煤、底板巷消除地应力方面有了很大的发展,因此,开展水力射流技术在本煤层强化瓦斯抽采方面的研究具有重要意义。采用水力射流扩大钻孔的直接影响范围,通过对扰动煤体的体积、表面积、单孔瓦斯抽采量、钻孔影响半径的考察,对比分析了水力射流技术和钻孔抽采技术的数据,得出钻孔直径增大11.7～19.2倍,扰动煤体体积提高3 471～6 971倍;钻孔瓦斯衰减周期延长了7～10倍;单孔抽采效果提高6～8倍。

Hydraulic Pressure Relief and Increasing Permeability Technology of Cross Hole

Low permeability coal seam gas drainage is the bottleneck of China's coal mine gas control.In recent years,water jet technology has been greatly developed in rock cross-cut coal uncovering and the elimination of ground stress.Therefore,carrying out water jet technology to strengthen the coal seam gas drainage is important.Using hydraulic jet to expand the direct influence range of drilling,through the investigating of volume,surface area,single-hole gas extraction amount and drilling affect radius of disturbance coal,the datum of the hydro-jet technology and drilling extraction technology are compared and analyzed.The paper achieves that the borehole diameter increases 11.7 to 19.2 times,the volume of the disturbance coal increases 3 471 to 6 971 times;The borehole gas decay cycle extends 7 to 10 times,the single hole drainage effect increases from 6 to 8 times.