Application of wetting agent in water injection of hydrophobic and difficult permeability coal seam

On the basis of introducing the mechanism of increasing permeability of wetting agent, taking the comprehensive excavation face of hydrophobic and difficult to penetrate coal seam as the test object, through the test of capillary reverse osmosis in the laboratory, the economic and reasonable concentration of 0.6% wetting agent solution for coal seam water injection is determined. In the field, we use clear water and wetting agent solution to carry out the coal seam water injection test, and make a comparative analysis of the technical effect of coal seam water injection. Using clear water to carry out coal seam water injection, the coal seam wetting radius is less than 0.5m, using wetting agent solution to carry out coal seam water injection, the coal seam wetting radius can reach more than 1.5m. The efficiency of water injection with wetting agent solution is 43.06% higher than that with clean water.