Application of Borehole Hydraulic Flushing Technology to Soft and Outburst Seam with Low Permeability

According to the present status of the soft and low permeability seam in Luobo'an Mine , Jiahe County,a borehole hydraulic flushing and permeability mea sures were selected. The borehole hydraulic flushing and permeability mechanism and the basic technical procedure were introduced.The application effect of the boreh ole hydraulic flushing in the soft and low permeability and outburst seam region for the gas drainage and outburst elimination measures was studied. The study showed t hat the application effect of the borehole hydraulic flushing in the soft and low permeability outburst seam region for the gas drainage and outburst prevention measures was obvious.seven tons of coal could be flushed from one single borehole 558.3 m3 gas could be flushed from one single borehole,the equivalent borehole diameter of the drainage borehole was improved by 13.38 times,the effective drainage influence radius of the borehole could be improved by 23 times,the pre-drained gas content 0 f the borehole could be improved by 45 times, the drainage attenuation period could be improved over 3 times.