摘要
顶煤冒放性是决定特厚煤层综放工作面煤炭资源回收率和安全生产的关键因素,水压致裂则是提高顶煤冒放性的有效技术之一。以小庄煤矿40309工作面为研究对象,采用理论分析、理论计算,结合现场监测(钻孔窥视、微震和矿压监测)和现场调研,对特厚煤层综放工作面水压致裂技术的应用开展研究。研究结果表明:(1)顶煤大厚度夹矸和裂隙发育程度低导致工作面回采率低和端头长时间悬顶。(2)水压致裂能有效扩张煤(岩)体原生裂隙,破坏煤(岩)体结构;水压致裂提高了顶煤覆岩压力2.5%~6%,增加顶煤破碎程度;微震事件总能量和频次增加1.98倍和1.70倍。(3)采取水压致裂措施后,工作面端头悬顶时间缩短53.3%,工作面回采率增加1.9%。
Caving ability of top coal is the key factor of comprehensive caving working face in extrathick coal seam,which will determine the rate of coal recovery and safe production.Hydraulic fracturing is one of the effective techniques to improve top coal caving.Rearding the No.40309 face of Xiaozhuang coal mine as the research object,analyzed the application of hydraulic fracturing technology in extrathick coal seam by theoretical analysis and calculation,field monitoring(drilling peep and water pouring statistics,microseism and rock pressure monitoring)and field investigation.The result shows that:(1)The large thickness of partings and the low development of top coal fractures lead to the poor caving ability of top coal.(2)Hydraulic fracturing can effectively expand the fracture of top coal;Hydraulic fracturing increased the overburden pressure of top coal by 2.5%-6%,which increase the fracture of top coal;The total energy and frequency of microseismic events increased by 1.98 times and 1.70 times,respectively.(3)Having been taken the measures of hydraulic fracturing,the hanging time of top coal is shortened by 53.3%,and the recovery rate of it is increased by 1.9%.
作者
李仕牧
柳东林
李凡
LI Shimu;LIU Donglin;LI Fan(Shaanxi Binchang Xiaozhuang Mining Co.,Ltd.,Xianyang 713500,China)
出处
《煤炭技术》
CAS
北大核心
2022年第9期125-129,共5页
Coal Technology
关键词
特厚煤层
综放工作面
水压致裂
顶煤冒放性
extra-thick coal seam
comprehensive caving working face
hydraulic fracturing
caving ability of top coal
