大倾角碎软低渗煤层封孔提浓成套技术
Complete Set of Technology of Hole Sealing and Concentration Increasing in Big Dip Broken Soft and Low Permeability Coal Seam
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摘要: 新疆艾维尔沟矿区大倾角碎软低渗煤层存在预抽瓦斯浓度低且衰减快问题,抽采效果不理想。为解决该技术难题,基于围岩应力和裂隙带分布特征确定合理封孔参数,根据管流流体力学理论,研发了抽采钻孔封孔参数检测装备,实现了封孔深度、密封效果等参数的检测检验;提出了径向膨胀主动承压注浆封孔工艺,设计研制新型浆体膨胀封孔材料及工艺装备,形成了适合新疆地区大倾角多煤组赋存条件的高效封孔提浓成套技术装备。结果表明:通过在新疆焦煤二一三〇煤矿应用试验,经检测抽采钻孔封孔深度应超过12 m,试验钻孔封孔注浆压力达到1.5 MPa,单孔瓦斯抽采浓度提高比例在96%以上,抽采效果大幅改善。Abstract: The large dip and broken soft low permeability coal seam in Ewirgol Mining Area in Xinjiang has the problems of low pre-drained gas concentration and fast attenuation, and the extraction effect is not ideal. In order to solve this technical problem, a reasonable hole sealing parameter was determined based on the surrounding rock stress and crack zone distribution characteristics, according to the theory of pipe flow hydrodynamics, the equipment for testing the parameters of the drilling hole sealing was developed, and the testing and inspection of the sealing depth and sealing effect were realized. The radial expansion active pressure grouting sealing technology was proposed, and a new design was developed. The slurry expansion sealing material and process equipment have formed a complete set of high-efficiency sealing and concentration increasing technology equipment suitable for the occurrence conditions of large inclination multiple coal groups in Xinjiang. The results show that through the application test in Xinjiang Coking Coal No.2130 coal mine, the borehole sealing depth of the tested drilling should exceed 12 m, the grouting pressure of the borehole sealing of the test borehole reached 1.5 MPa, and the single-hole gas drainage concentration increased by 96% more than 96%, the extraction effect has been greatly improved.