低透气性突出煤层煤巷“三带”的研究与应用

针对车集煤矿2309工作面煤层瓦斯含量较高、煤层透气性较差等问题，采用Origin数值分析，对2309工作面切眼两侧顺层钻孔内瓦斯浓度变化规律及2309工作面切眼两侧卸压带宽度进行了研究。研究得出:2309工作面切眼卸压带内宽度自巷道左帮开始为0~12.7 m，应力集中带位于12.2~16.7 m，原始应力区为大于16.7 m。因此，2309工作面向前掘进时进尺不大于12.7 m，且对本煤层施工的顺层钻孔封孔长度不小于12.7 m，才能够有效保证钻孔的抽采效果；同时根据钻孔瓦斯浓度衰减规律，要求顺层钻孔在封孔结束后30 d内必须保证抽采负压，确保钻孔的抽采效果。研究为矿井的瓦斯抽采和巷道掘进速度提供技术支撑，有效保证了突出煤层瓦斯防治的治理水平。

Research and application of "Three Zone" for coal seams with low permeability outburst seam

In view of the problems such as high gas content and poor gas permeability of coal seam on 2309 working face of Juji Coal Mine，using the numerical analysis of Origin，the change rule of gas concentration in the boreholes along the sides of the 2309 working face and the width of the pressure relief strip on the 2309 sides of the cut face were studied.The results showed that the width of cut relief in 2309 working face is 0~12.7 m from the left-hand side of the roadway，the stress concentration zone is in the range of 12.2~16.7 m，the original stress zone is larger than 16.7 m.Therefore，when the 2309 working face moves forward，the advance footage is no more than 12.7 m，and the sealing length of the straight borehole in the coal seam construction is not less than 12.7 m，which can effectively ensure the drilling drainage effect.Meanwhile，the law of concentration attenuation requires that the vertical drilling must ensure the negative pressure of pumping during the 30 days after sealing，so as to ensure the pumping effect of drilling.The research provides technical support for mine gas drainage and roadway driving speed，effectively ensures the control level of the outburst coal seam gas prevention and control and improves the efficiency of mine gas treatment.