摘要
在工作面回采中,坚硬顶板的完整性较好,自稳能力强,在采后会形成大面积悬顶,严重威胁工作面人员和设备的安全。为实现安全回采,在东峰煤矿21902工作面开展了工作面初采坚硬顶板切顶卸压技术的研究。通过对比3种不同切顶方式的优缺点,结合煤层的地质条件,确定采用水力压裂切顶的方式。在确定切顶高度和角度的基础上,设计布置压裂钻孔27个,长度15 m,仰角为45°,垂直高度10.6 m。现场应用表明,每个点的压裂时长约为30 min,压力13.3~21.8 MPa。钻孔窥视表明,石灰岩出现了明显的裂隙,具有平行于巷道方向的破碎带初次来压步距减少67.5%,取得了理想的压裂效果。
In the mining of the working face,the integrity of the hard roof is good,and the self-stabilizing ability is strong.After mining,a large area of suspended roof will be formed,which seriously threatens the safety of personnel and equipment in the working face.In order to realize safe mining,the research on roof cutting and pressure relief technology of hard roof was carried out in No.21902 Face of Xinyuan Mine.By comparing the advantages and disadvantages of three different roof cutting methods,combined with the geological conditions of the coal seam,the hydraulic fracturing roof cutting method was determined.On the basis of determining the height and angle of roof cutting,27 fracturing boreholes were designed and arranged,with a length of 15 m,an elevation angle of 45°and a vertical height of 10.6 m.Field application showed that the fracturing time of each point was about 30 min,and the pressure range was 13.3~21.8 MPa.Borehole peep showed that there were obvious cracks in limestone,and the initial pressure step of the fracture zone parallel to the roadway direction was reduced by 67.5%,and the ideal fracturing effect was achieved.
作者
汪隆靖
Wang Longjing(CCTEG Chongqing Research Institute,Chongqing 400037,China)
出处
《煤炭与化工》
2025年第11期54-57,共4页
Coal and Chemical Industry
