CHINA MINE ENGINEERING

To explore the expansion trend of CO₂ phase change blasting cracking in different drillhole spacings and its application value in coal seam methane mining, CO₂ phase change blasting cracking experiments were carried out in Anshun Hongfa Coal Mine, Guizhou Province, for comparison with the result of numerical simulation of crack growth by LS-DYNA. The research shows that under the same conditions in the field test, the carbon dioxide phase change blasting has the best cracking effect with a drillhole spacing of 10m, and the permeability coefficient of the coal seam can reach about 3 times that of the original coal seam after CO₂ phase change blasting and fracturing. In the software simulation, the crack propagation of the coal seam with a drilling spacing of 10m is optimal.