摘要
针对瓦斯抽采钻孔周围煤岩体裂隙贯通和封孔材料失效导致漏气,造成钻孔抽采瓦斯浓度和纯流量大幅度下降并无法达到抽采预期目标的问题,分析了造成钻孔漏气的主要原因,提出一种具有普适性的失效钻孔修复技术,即通过数值模拟分析得到应力增高区和原岩应力区的交界位置,并在此处施工环形缝槽,辅以“两堵一注”带压注浆封孔工艺,对失效钻孔进行修复处理。现场试验结果表明:失效钻孔修复后,平均抽采瓦斯浓度提高3倍以上,平均抽采瓦斯纯流量提高50%以上,并有效延长了钻孔服务寿命。
In view of the problem that gas leakage is caused by fracture connection of coal and rock around gas extraction borehole and failure of sealing material,which leads the concentration and net flow of gas extracted from borehole decreases greatly and the expected target of extraction can’t be achieved,this paper analyzes the main causes of air leakage in borehole and puts forward a universal repair technology for failure borehole.That is,through numerical simulation analysis,the junction position of the stress increase zone and the stress zone of the original rock is obtained,and the annular slot is constructed here,supplemented by the“sealing two sections and grouting in the middle”with pressure grouting sealing technology,to repair the failure borehole.The field test results show that after the failure hole is repaired,the average gas extraction concentration increases by more than 3 times,the average gas extraction net flow increases by more than 50%,and the service life of the borehole is effectively prolonged.
作者
熊伟
XIONG Wei(State Key Laboratory of the Gas Disaster Detecting,Prerending and Emergency Controlling,Chongqing 400037,China;CCTEG Chongqing Research Institute,Chongqing 400037,China)
出处
《矿业安全与环保》
北大核心
2020年第1期80-83,共4页
Mining Safety & Environmental Protection
基金
国家科技重大专项(2016ZX05067004-004,2016ZX05043005-003)
企业科技创新创业资金专项项目(2018QN005,2019-TD-QN038)
关键词
瓦斯抽采
钻孔密封
钻孔漏气
失效钻孔
修复技术
水力割缝
gas extraction
borehole seal
gas leakage through borehole
failure borehole
repair technology
hydraulic slotting
