摘要
为了解决深井高地应力低透气性强突出中硬煤层瓦斯抽采钻孔工程量大、抽采时间长、瓦斯灾害频发的难题,通过对中压水力割缝破煤机制、设备构成、割缝工艺技术流程进行研究,提出煤体顺层长钻孔中压水力割缝卸压增透技术,并在中煤新集二矿220108工作面1煤层开展工程实践。结果表明:中压水力割缝增大了煤体内暴露空间体积,割缝等效半径可达到1.25~1.95 m;割缝钻孔瓦斯涌出初速度增大了7.3倍,瓦斯涌出衰减系数降低了73.1%;割缝钻孔抽采瓦斯浓度提高了1.8倍,抽采瓦斯纯流量提高了1.3倍,实现了持久高浓度连续抽采。与未割缝普通钻孔相比,割缝钻孔抽采15、30 d的钻孔抽采半径分别增大34.8%、32.2%,可有效缩短瓦斯抽采达标时间,同时减少了瓦斯治理工程量,能够解决采掘接替失衡难题,实现强突出煤层的安全高效开采。
In deep wells gas extraction with high geostress,low gas permeability,and prominent medium hard coal seams,the volume of gas drainage drilling projects is large,the drainage time is long,and gas disasters are frequent.In order to solve these problems,based on the study of the medium pressure hydraulic slotting mechanism,equipment composition and technical process of slotting,the pressure relief and anti-reflection technology for medium pressure hydraulic slotting in long boreholes along coal seams was proposed,and the engineering practice was carried out in No.1 coal seam of 220108 working face in Xinji No.2 Coal Mine.The results show that the medium pressure hydraulic slotting increases the volume of exposed space in coal mass,and the equivalent radius of the slotting can reach 1.25 m to 1.95 m;the initial velocity of gas emission from the slotting increases by 7.3 times,and the attenuation coefficient of gas emission decreases by 73.1%;the drainage concentration of slotting borehole is increased by 1.8 times,and the drainage volume is increased by 1.3 times,so as to achieve continuous high-concentration drainage.Compared with unslotting ordinary boreholes,the extraction radius of drainage for 15 d and 30 d is increased by 34.8%and 32.2%,respectively,which can effectively shorten the time of drainage compliance,reduce the amount of gas control projects,and solve the problem of unbalanced mining replacement,and achieve safe and efficient mining of strong outburst coal seams.
作者
乔伟
QIAO Wei(State Key Laboratory of the Gas Disaster Detecting,Preventing and Emergency Controlling,Chongqing 400037,China;CCTEG Chongqing Research Institute,Chongqing 400037,China)
出处
《矿业安全与环保》
北大核心
2022年第2期122-126,共5页
Mining Safety & Environmental Protection
关键词
卸压增透
中压水力割缝
割缝工艺
衰减系数
抽采效果
pressure relief and anti-reflection
medium pressure hydraulic slotting
slotting process
attenuation coefficient
drainage effect
作者简介
乔伟(1986-),男,河南新野人,硕士,副研究员,主要从事矿井瓦斯灾害防治研究工作。E-mail:403229474@qq.com。
