Rapid Seam Opening and Outburst Prevention Technology of Three Soft Seam with Deep Depth and High Outburst

According to the high outburst dangerproblem in No.B1 seam in Xinyi Mine, with the analysis on the advantage and disadvantage of the different outburs t prevention technical measures for the seam opening working face at the crosscut, the side cut-off of the gateway, the cross borehole gas drainage in the gateway with the standing blasting in the short pilot chamber were applied to rapidly open the three soft seam with serious outburst. The results showed that with 40 days gas drainag e operation, the gas drainage rate of the seam opening working face was reached to 34.6%. Before the seam opened, the previous gas content was 6.3712.84 m3/t.After the outburst prevention measures with the centralized gas drainage conducted, the residual gas content value would be 6.508.00 m3/t.Before the seam opened, the out burst prevention measures effect inspected the drilling cutting gas desorption index Oh2 of the seam opening working face and the max value was 80 Pa.The above me asured index could show that after the rapid seam opening technology applied in the three soft seam with serious outburst, the outburst danger of the seam opening wo rking face was eliminated. After the standing blasting applied to the seam opening, the max value of the gas volume fraction would be only 0.04% and the No.B1 seam W as safety and successfully opened.