Technology of Liquid Carbon Dioxide Deep Hole Blasting Enhancing Permeability in Coal Seam

In order to improve gas drainage rate in low permeability high gas outburst coal seam,CO2 deep hole blasting enhancing permeability technology was attempted to apply to the low permeability and high outburst coal seam in certain coal mine. By designing blast parameters,an application test was conducted,and the blasting effects were studied by analyzing such as coal seam gas permeability coefficient,gas flow of 100 meters drilling hole,gas drainage quantity,gas drainage coefficient,and outburst prediction sensitive indexes. After applying CO2 pre-split blasting enhancing permeability technology,it further extends the efficient draining radius and increases the coal permeable,and finally raises the coal seam's gas-extracting quantity and gas-extracting rate.