低渗煤层高压水射流割缝增透技术试验研究

Experimental study on permeability improvement technology by cutting seam using high pressure water jet in coal seam with low permeability

霍尔辛赫煤矿为高瓦斯矿井，3号煤层为较难抽放煤层，如何有效增加3号煤层透气性、提高瓦斯抽采效果，成为矿方亟需解决的问题。为此，采用自主研发的瓦斯抽采孔水力作业机，开展了低渗煤层高压水射流割缝增透抽采瓦斯技术试验研究。研究表明：经高压水射流割缝后，瓦斯抽采钻孔的平均抽采浓度增加3．87～9．31倍，平均抽采纯量增加2．67～7．33倍，增透效果显著；割缝钻孔出煤量为2．3～3．4 t，使钻孔周围煤体地应力得以有效释放，这也正是瓦斯抽采效果显著提高的主要原因。

Huoerxinhe Mine is a high gas coal mine, and the No.3 coal seam is difficult to drainage.How to effec-tively increase the permeability of No.3 coal seam and improve gas drainage effect have become the problem which needs to be solved as soon as possible.Therefore, by applying the self-developed gas drainage hole hydraulic ma-chine, the experimental study on permeability improvement technology by cutting seam using high pressure water jet in coal seam with low permeability was carried out.It showed that after cutting seam using high pressure water jet, the average drainage concentration of gas increased by 3.87~9.31 times, the average drainage pure quantity in-creased by 2.67~7.33 times, and the effect of permeability improvement was remarkable.The coal output of cut-ting seam borehole was 2.3~3.4 t, which made the stress of coal body around the borehole can be effectively re-leased, which is the main reason for the obvious increase of gas drainage effect.