中国矿山工程

In order to promote the effect of coal seam gas drainage, the surface fracturing method is adopted by Tunlan Mine to improve the coal seam gas permeability, and parameters of surface fracturing boreholes and coal seam permeability enhancement are set up. After surface fracturing is applied on site, the 2# fracturing area presents an oval shape with surface fracturing well in the center and two axes of 100m and 40m; after fracturing, the coal seam permeability coefficient, gas drainage concentration and purity have increased by 227.2%, 170% and 158% respectively, which indicates that the surface fracturing improves the gas drainage effect significantly.