相邻工作面采动影响下瓦斯预抽钻孔封孔技术研究

发布时间：2018-03-06 13:35

本文选题：煤层瓦斯预抽　切入点：松动圈　出处：《煤炭科学技术》2017年12期 　论文类型：期刊论文

【摘要】：为解决余吾煤业井下瓦斯预抽钻孔抽采瓦斯浓度低的问题,对该矿不同巷道预抽钻孔抽采浓度进行了调查分析。认为相邻的回采工作面采动影响对巷道内预抽钻孔抽采瓦斯浓度的影响最大。采用理论分析和现场实测相结合的方法,研究得出采动影响区域预抽钻孔抽采瓦斯浓度低的原因为:采动影响范围内,受应力增高影响,巷道围岩松动圈厚度增大,预抽钻孔封孔时封孔注浆段没有避开围岩松动圈,所注浆液沿裂隙泄露,造成封孔失效。针对采动影响区域,提出了增加封孔深度、减小封孔长度的新型封孔方法。实践证明:采用新型封孔方法,受采动影响巷道瓦斯预抽钻孔的抽采浓度明显提升,接近80%钻孔的抽采瓦斯体积分数能达到30%以上,体积分数在30%以上的钻孔占比将近原来的10倍。
[Abstract]:In order to solve the problem of low gas concentration in underground gas pre-drainage hole in Yuwu coal industry, This paper makes an investigation and analysis on the concentration of pre-drainage borehole extraction in different roadways in this mine. It is considered that the influence of adjacent mining face on the concentration of gas extracted by pre-drainage boreholes in the roadway is the greatest. The method of combining theoretical analysis with field measurement is adopted. The reasons for the low concentration of gas extracted by pre-drainage boreholes in the area affected by mining are as follows: in the affected area of mining, the thickness of surrounding rock loose circle increases due to the increase of stress, and the grouting section of sealing hole does not avoid the loosening circle of surrounding rock when pre-drainage hole is sealed. The grouting fluid leaks along the fissure, which results in the failure of sealing holes. A new sealing method, which increases the depth of sealing holes and reduces the length of sealing holes, is put forward for the area affected by mining. The practice proves that the new method of sealing holes is adopted. The extraction concentration of gas pre-drainage boreholes in roadway affected by mining movement is obviously increased. The gas extraction volume fraction of nearly 80% boreholes can reach more than 30%, and the proportion of boreholes with volume fraction above 30% is nearly 10 times of that of the original boreholes.
【作者单位】：中煤科工集团重庆研究院有限公司;
【基金】：国家科技重大专项资助项目(2016ZX05067004-004,2016ZX05043005-003)
【分类号】：TD712.6

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