Shaanxi Huangling No. 2 Coal Mine Co., Ltd.

为确定适合陕西黄陵二号煤矿顺层瓦斯抽采钻孔的合理封孔长度,开展基于钻孔应力状态分布特征的封孔长度分析,并运用巷道弹塑性软化模型定量得到符合黄陵二号煤矿地质条件的瓦斯抽采钻孔峰后应力升高区半径,通过理论计算确定该矿井的最佳封孔长度为12m。在此基础上应用双囊袋一体化封孔技术替代传统聚氨酯材料实施封孔,预抽钻孔平均瓦斯浓度由14.2%提升至30.2%,取得良好的瓦斯抽采效果。

To determine the reasonable sealing length for gas extracting boreholes along the seam in Shaanxi Huangling No. 2Coal Mine, a sealing length analysis based on the stress state distribution characteristics of the boreholes is carried out, andthe elastic-plastic softening model of roadway is adopted to quantitatively obtain the radius of the post-peak stress increasingzone of gas extracting boreholes under the geological conditions of the mine. The optimal sealing length for the mine is determined to be 12 m by theoretical calculation. The double-bag integrated sealing technology is applied to replace the traditional polyurethane material for sealing, and the average gas concentration of pre-extraction boreholes is increased from 14. 2%to 30. 2% , achieving good gas extraction effect.