Study on Radial Swelling and Permeation Borehole Sealing Technology of Gas Drainage Borehole

According to the serious air leakage of the gas drainage borehole in the mining seam, low drained gas content and short effective gas drainage period, t his paper analyzed the air leakage mechanism and key technology of borehole sealing of the gas drainage boreholes in the mining seam, provided the radial swelling a nd permeation sealing technology of the gas drainage borehole in the mining seam and stated the technical principle of the technology to seal the borehole with crack Z one around the borehole. Finally, combination with the cases, a rational borehole sealing depth of the gas drainage borehole for No. 2210 coal mining face in a mine wa s determined as 16 m. The experiment showed that with the application of the radial swelling and permeation sealing technology, the fraction of the gas drainage volum e was increased by 21% ~ 32%, the average gas drainage flow was increased by 0.016 m3/ min and the gas drainage period could be extended by 1 ~ 2 months. Thu s a safety and high efficient gas drainage could be ensured and the waste of the sealing material and the formation of the gas drainage blind zone could be avoided.