Permeability improvement technology of array crossing boreholes and its application in outburst coal seam

A new permeability improvement technology of array crossing boreholes was described and studied in detail,and the permeability improvement mechanism was put forward and analyzed.The in-situ experimental results show that the technology can eject coal from outburst seam,lead the remainder ones to loose pressure and extend fracture,and improve the coal permeability by an average of 150 times and the borehole flow by an average of 4 times.