屯兰煤矿超前排放钻孔有效排放半径的研究

Study on Effective Discharge Radius of Advance Drill Hole in Tunlan Coal Mine

为了解决屯兰煤矿防突措施中超前排放钻孔孔径选取和钻孔布置的问题,根据钻孔瓦斯涌出量与排放时间的关系,测定钻孔瓦斯涌出量变化率以确定超前钻孔的有效排放半径。结果表明:屯兰煤矿2^#、4^#、8^#和9^#煤煤层超前钻孔的有效排放半径分别为0.5m、1m、0.5m、0.5m,为屯兰煤矿超前排放钻孔的设计提供了依据,提高了防突措施效果。

In order to select borehole diameter and design borehole layout for outburst prevention in Tunlan Coal Mine, according to the relationship between gas emission and drainage time, the change rate of borehole gas emission was measured to determine the effective drainage radius of the advance borehole. The results show that the effective discharge radius of advance boreholes in No.2, No.4, No.8 and No.9 coal seams of Tunlan Coal Mine are 0.5 m, 1 m, 0.5 m and 0.5 m respectively. It provides a basis for the design of advance discharge boreholes in Tunlan Coal Mine and improves the outburst prevention effect.