Application Study on Hydraulic Fracturing and Deep Hole Pre-splitting Blasting Joint Permeability Improvement Technology

In view of the complicated geological structure, poor permeability and poor extraction efficiency of the No.8 coal seam in the northern of Lubanshan Mine, the combined technology of hydraulic fracturing and deep hole pre-splitting blasting in the coal seam of No.8 coal seam is carried out in 152 floor roadway. The results show that the technology is better than hydraulic fracturing technology, deep hole pre-splitting blasting technology and ordinary extraction technology, which improves the permeability of coal seam. The pure volume of gas extraction is 1.55 times higher than that of hydraulic fracturing, and it is 1.39 times that of deep hole pre-splitting blasting and 2.3 times of normal extraction. The combined concentration of hydraulic fracturing combined with deep hole pre-cracking permeability improvement technology remains over 42% without attenuation.