Analysis on Gas Drainage Based on High-Pressure Water Injection
Gas outburst has been a major disaster in high gas mine. Flow law of gas in coal seam was studied, and gas drainage measures were proposed were extraordinarily useful for mine safety and rational use of gas. Finite element numerical method was applied to study changing law of gas pressure before and after the high-pressure water injection and damage deformation of coal under high-pressure water based on fluid-solid coupling and gas-solid coupling and damage theory. This research shows that: (1) a damage area was generated in coal seam under high-pressure water injection. Range of the damage area increase rapidly at the start of water injection and gradually slow down with the passage of time, eventually be more stable. (2) The permeability of rock mass of coal under high-pressure water injection. (3) High-pressure water injection had significant effect on gas drainage in a certain area. It provided a theoretical basis for selecting reasonable design programs to product gas by high-pressure water injection technology.