覆岩采动卸压瓦斯高位钻孔抽采技术

1.西安科技大学 能源学院,陕西 西安 710054; 2.教育部 西部矿井开采及灾害防治重点实验室,陕西 西安 710054

低透气性煤层; 外错高抽巷; 采动裂隙; 卸压瓦斯; 高位钻孔

High level borehole drainage technique of the overlying strata mining-induced pressure-relief gas
SHUANG Hai-qing1,WANG Hong-sheng1,2,LI Shu-gang1,2,

(1.College of Energy Science and Engineering,Xi'an University of Science and Technology,Xi'an 710054,China; 2.Key Laboratory of Western Mine Exploration and Hazard Prevention,Ministry of Education,Xi'an 710054,China)

low permeability coal seam; lateral high drainage roadway; mining-induced fissure; pressure-relief gas; high level borehole

DOI: 10.13800/j.cnki.xakjdxxb.2015.0602

备注

为解决工作面隅角瓦斯超限难题,提出了在外错高抽巷内布置高位钻孔抽采工作面覆岩采动卸压瓦斯方法。针对李雅庄煤矿2-603工作面开采技术条件,建立了高位钻孔围岩结构力学模型,采用理论分析、数值模拟分析及现场实测分析等方法,确定了外错高抽巷内高位钻孔终孔合理位置。首先,覆岩采动裂隙主要分布在上山采动角62°以内,下山采动角65°以内,距离煤层底板13~25 m和38.6~50 m等2个区域,高位钻孔终孔应布置于第二区域内。其次,高位钻孔终孔位于2煤顶板44 m处,采空区内投影长度不小于28 m时,钻孔抽采瓦斯浓度高,且持续抽采时间长。最后,工程应用效果表明,2-603工作面上隅角瓦斯浓度生产班、检修班分别为0.50%~0.95%,0.47%~0.89%,避免了隅角瓦斯超限,保障了工作面安全高效回采。

To solve the problem of the gas consistence exceeding limit at the corner of coalface,a new method that pressure-relief gas in fractured zone of the upper section coalface's overlying strata was extracted by high level boreholes in lateral high drainage roadway was proposed.Based on the mining technology conditions of the No.2-603 coalface of Liyazhuang coal mine,mechanical model of the high level borehole was established,the reasonable final hole position of the high level borehole was determined by theoretical analysis,numerical simulation and field observing analysis.Firstly,the fractured zone was at the height of 13~25 m,38.6~50 m to the floor,and in the rise-entry mining angle of 62°,and in the down-entry mining angle of 65°,and the final location have been layouted at the second zoon.Secondly,the borehole's final hole position was 44 m high over the roof,and the projection length of the borehole was not less than 28 m in the gob,and the value of the gas concentration was high,and the draining time was long.Finally,the engineering application effect showed that the problem of the gas consistence exceeding limit was solved,the gas consistence at the upper corner were 0.50%~0.95% and 0.47%~0.89%,and the coalface was mined safely and effectively.