极薄保护层钻采上覆突出煤层卸压瓦斯抽采技术

采用数值模拟和现场试验相结合的方法,系统地研究了极薄保护层钻采过程中上覆被保护煤层地应力及煤层变形的变化规律和煤层卸压瓦斯流动及瓦斯抽采规律。极薄保护层钻采后,被保护煤层弯曲下沉、卸压膨胀变形,煤层透气性提高了403倍,通过向被保护煤层施工网格式上向穿层钻孔进行卸压瓦斯抽采,被保护煤层瓦斯压力和瓦斯含量降低,消除了煤与瓦斯突出危险,成功实现了矿井安全高效生产。

Pressure Relief Gas Drainage Technology of Overlying Putburst Coal Seam Caused by Drilling Extremum Thin Seam

Numerical simulation and field test were adopted to investigate the change law of ground stress,deformation,pressure relief gas flow and gas drainage of the protected coal seam in the extremum thin protective layer exploitation.The results show that the protected coal seam is integrally bending and sinking,the expansion deformation is produced,and the permeability coefficient of the coal seam increases 403 times.The grid penetration boreholes are drilled evenly toward the protected coal seam for pressure relief gas drainage.The gas pressure and gas content decrease,the danger from coal and gas outburst has been eliminated and a safe and highly efficient production is successfully achieved.