厚硬顶煤多维水力压裂增加冒放性技术  

Multi-dimensional hydraulic fracturing technology for thick and hard top coal to increase caving

作　　者：李良伟 武文宾 孙朋[1,2] 潘雪松 LI Liangwei;WU Wenbin;SUN Peng;PAN Xuesong(Chongqing Research Institute,China Coal Technology and Engineering Group,Chongqing 400037,China;State Key Laboratory of the Gas Disaster Detecting,Preventing and Emergency Controlling,Chongqing 400037,China)

机构地区：[1]中煤科工集团重庆研究院有限公司,重庆400037 [2]瓦斯灾害监控与应急技术国家重点实验室,重庆400037

出　　处：《中国矿业》2022年第5期150-156,共7页China Mining Magazine

基　　金：国家科技重大专项项目资助(编号:2016ZX05045004002);山东省重点科技创新工程项目资助(编号:2019SDZY02)。

摘　　要：针对厚硬煤层放顶煤开采时顶煤冒放性差的问题,通过现场试验研究了超前水力压裂结合支架间水力压裂的过程规律,考察了采取措施后顶煤的冒放效果。结果表明:①超前水力压裂的压力峰值在14~20 MPa之间,压裂总时间在74~138 min之间。H1号钻孔和H3号钻孔比H2号钻孔的压裂持续时间长,压力峰值高。②支架间水力压裂的压力峰值在18~22 MPa之间,压裂总时间在15~27 min之间。上端头的水压峰值较下端头水压峰值更高,压裂持续时间也更长。③超前水力压裂钻孔较深,控制范围大,压裂时间长但压力峰值低;支架间水力压裂钻孔浅,控制范围小,压裂时间短但压力峰值高;超前水力压裂钻孔平均压入水量约为支架间水力压裂钻孔平均压入水量的5倍。④试验工作面水力压裂稳定期的放煤高度较未进行水力压裂区域增加82%,已接近最佳采放比。Aiming at the problem of poor top coal caving performance during top coal caving mining in thick and hard coal seams,the process law of advanced hydraulic fracturing combined with hydraulic fracturing between hydraulic supports is studied through field tests.The results show that the peak pressure of advanced hydraulic fracturing is 14-20 MPa,and the total fracturing time is 74-138 minutes.Hole H1 and hole H3 have longer fracturing duration and higher pressure peaks than hole H2.The peak pressure of hydraulic fracturing between hydraulic supports is 18-22 MPa,and the total fracturing time is 15-27 minutes.The peak water pressure at the upper end is higher than that at the lower end,and the fracturing lasts longer.The advanced hydraulic fracturing hole is deeper,the control range is large,the fracturing time is long,but the pressure peak is low.The hydraulic fracturing holes between the hydraulic supports are shallow,the control range is small,the fracturing time is short,but the pressure peak is high.The average water injection rate of advanced hydraulic fracturing holes is about 5 times that of hydraulic fracturing holes between hydraulic supports.The coal caving height during the stable period of hydraulic fracturing at the test working face increased by 82%compared with the area without hydraulic fracturing,which is close to the optimal mining and caving ratio.

关 键 词：冒放性 顶煤压裂 封隔器 厚硬煤层 采放比 

分 类 号：TD823.97[矿业工程—煤矿开采]