摘要
针对沙曲矿近距离煤层群开采中的瓦斯防治问题,综合运用理论分析、数值模拟的方法对保护层开采时底板卸压效果进行分析,结合塑性区的发育形态编写fish语言获取被保护层中渗透系数的变化规律,并用于工程实践。结果表明:在2号煤层作为保护层开采的情况下,底板卸压深度可达20~36m,大于3+4号煤层与3号煤层之间的最大垂直距离,3+4号煤在上煤层的保护范围内;随着保护层的开采,被保护层渗透性系数明显提高,最大值可以达到5.2,虽然随着工作面推进覆岩垮落,渗透性系数会有所回落,但与初始值相比依然有较大提升;在2号煤层的回采时,对底板穿层钻孔进行了瓦斯浓度实测,钻孔中瓦斯浓度最大值可达到70%,抽采效果良好。
Aiming at the gas control problems when mining the contiguous coal seams in Shaqu Coal Mine,theoretical analysis and numerical simulation are used comprehensively to analyze the effect of floor stress relieving during protective layer mining,and combining with the development form of plastic zone,the variation law of permeability coefficient in the protected layer is obtained using fish language.The results show that when No.2 coal seam is mined as the protective layer,the stress relief depth of the floor can reach 20~36 m,which is greater than the maximum vertical distance between No.3+4 coal seam and No.3 coal seam,and No.3+4 coal seam is within the protected range of the upper coal seam.With the exploitation of the protective layer,the permeability coefficient of the protected layer is significantly increased,and the maximum value can reach5.2.The permeability coefficient,though falls as the working face continues to advance,is greatly improved compared.In the mining of No.2 coal seam,the gas concentration in floor seam-crossing borehole is measured,which can reach 70%,showing a favorable extraction effect.
作者
李海涛
闫大鹤
浦仕江
程志恒
李志亮
白爱卿
LI Hai-tao;YAN Da-he;PU Shi-jiang;CHENG Zhi-heng;LI Zhi-liang;BAI Ai-qing(Mine Safety Technology Branch of China Coal Research Institute,Beijing 100013,China;Shaqu No.1 Mine of Huajin Coking Coal Co.,Ltd.,Liulin 033300,China;Mining College of Guizhou University,Guiyang 550025,China;School of Safety Engineering,North China Institute of Science and Technology,Beijing,10160 China;Huake Zhongan Technology(Beijing)Co.,Ltd.,Beijing 102300,China)
出处
《煤炭工程》
北大核心
2020年第7期78-82,共5页
Coal Engineering
基金
国家重点研发计划资助项目(2017YFC0804206-002)
国家十三五重大专项(2016Z X05067005-005)
中央高校基本科研业务费资助项目(3142019005)。
关键词
近距离煤层群
保护层开采
卸压范围
渗透性系数
抽采效果
close coal seams
protective layer mining
stress relief range
floor extraction tunnel
extraction effect
