Effects and influencing factors of the CO2-alkaline-water two-phase displacing gas and wetting coal

•After using the CADW, the amount of residual gas in coal increased significantly.•The water injection volume and moisture content in coal all increased obviously.•The coal permeability decreased by more than one order of magnitude.•Increasing injection pressure and time can distinctly improve effects of the CADW.•The CADW’s effect will reduce with rising ground stress and reducing temperature.