摘要
超高压水射流割缝技术能显著改善深部煤层的应力状态、减少抽采钻孔工程量。针对割缝作业工艺参数选取缺少依据、易导致割缝误穿透相邻钻孔、卸压增透效果差等问题,开展了大埋深条件下的突出煤层超高压水射流割缝工艺参数研究。首先,理论分析了水射流压力、割缝时间、水射流旋转速度等工艺参数对超高压水射流割缝效果的影响;然后,通过不同参数下水射流割缝卸压增透效果现场考察,获得最佳水射流割缝工艺参数组合;最后,在赵固二矿西胶带大巷进行现场工艺验证。试验结果表明:优化后的煤层割缝钻孔抽采瓦斯纯量为对比钻孔的3.8倍,割缝钻孔有效瓦斯抽采半径为对比钻孔的2倍,割缝后穿层钻孔设计参数由4 m×5 m优化为8 m×5 m布置,在钻孔工程量减少50%的基础上,抽采达标时间由12个月以上缩短为7个月,抽采达标时间缩短了约40%。
The technology of ultra-high pressure water jet slotting can significantly improve the stress state of deep coal seam and reduce the amount of drilling work.In view of the problem that due to the lack of evidence for the selection of slotting process parameters,it is easy to cause the slotting to penetrate the adjacent borehole by mistake and the effect of pressure relived and permeability enhanced is poor.In this paper,the technological parameters of ultra-high pressure water jet slotting in outburst coal seam under the condition of large buried depth were studied.Firstly,the influence of technological parameters including water jet pressure,slotting time and rotation speed of water jet on the effect of ultra-high pressure water jet slotting was theoretically analyzed;secondly,by field investigation of pressure relived and permeability enhanced effect of water jet slotting under different parameters,the optimum parameters combination of water jet slotting were obtained;finally,the field process verification was carried out in the western belt roadway of Zhaogu No.2 Coal Mine.The test results show that the gas drainage purity of the optimized coal seam slotting borehole is 3.8 times that of the contrasted borehole,the effective gas drainage radius of the slotting borehole is 2 times that of the contrasted borehole.After slotting,the design parameters of perforating borehole were optimized from 4 m×5 m to 8 m×5 m,and on the basis of the 50%reduction of the drilling work,the time to reach the drainage standard has been shortened from over 12 months to 7 months,and the drainage time to reach the standard has been reduced by about 40%.
作者
李生舟
乔伟
王建
LI Shengzhou;QIAO Wei;WANG Jian(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
2020年第4期57-61,共5页
Mining Safety & Environmental Protection
基金
国家重点研发计划项目(2017YFC0804206)
中国煤炭科工集团有限公司科技创新创业资金专项(2018MS011)
中煤科工集团重庆研究院有限公司项目(2017YBXM31)。
关键词
超高压
水力割缝
深部煤层
卸压
瓦斯抽采
工艺参数
ultra-high pressure
hydraulic slotting
deep coal seam
pressure relief
gas drainage
process parameter
