To counter to the problems of difficult gas drainage from the outburst coal seam with low permeability and long outburst-elimination time, the gas geological conditions of 6-2 coal seam in a mine in Huanan Coal Mining Area was taken as an example, pressure grouting by deep and shallow holes was adopted to seal the rock cracks around the roadway and drilling site so as to improve the gas drainage effect;the concussion blasting by medium-deep holes was used to make the coal cracks to be well developed so as to enhance the gas permeability of the coal seam and improve the gas drainage rate. The engineering practice showed that the grouting by deep and shallow holes increased the hole gas drainage concentration by 7. 4 ~10. 5 times; the average pure gas drainage volume increased by 9. 2 times after concussion blasting by medium-deep holes, and the drainage time to the standard was 85 d, shortened by 4 months as compared to the traditional method. The grouting by deep and shallow holes was the key measure for improving gas drainage concentration, and the permeability enhancement with concussion blasting by medium-deep holes was the basic measure for improving the gas drainage volume by holes and shortening gas drainage time.%针对低透气性突出煤层瓦斯抽采困难、消突时间长等问题,以淮南矿区某矿6-2煤层具体瓦斯地质条件为例,采用深浅孔带压注浆技术措施封堵巷道及钻场深浅部围岩裂隙,改善瓦斯抽采效果;采用中深孔松动爆破技术措施使煤体裂隙充分发育,提高煤层透气性和瓦斯抽采率. 工程实践表明:深浅孔注浆技术提高钻孔瓦斯抽采浓度7. 4 ~10. 5 倍;中深孔松动爆破后平均抽采瓦斯纯量提高了9. 2倍,抽采达标时间85 d,比传统方法缩短了4个月. 深浅孔注浆是提高瓦斯抽采浓度的关键措施,中深孔松动爆破增透是提高钻孔抽采量、缩短抽采达标时间的基础措施,该技术还可保障矿井正常采掘接替.
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