Experimental study on decrease of gas gush strength led by active water

To solve gas overload problem in mining face, the relationship between gas pressure and exposure time in falling coal of mining face was analyzed. A series of methane absorption-degradation comparison experiments on immersed coal particles praevia and rear in active water and pure water were carried out by use of a methane absorption-degradation equipment in laboratory. Follow on, comparison experiments on methane desorption by spraying active water and pure water were carried out in falling coal of three driving faces in a coal mine. In conclusion, active water has the same gas desorption effect on both praevia and rear immersed coal particles. By spraying active water solution in falling coal of driving face, the methane desorption degree can be reduced 53.56%-54.76% than that of pure water. And the maximum gas inrush velocity in the beginning decreases 54.42%-71.29% than that of pure water. It is found that injecting or spraying active water under low pressure and high flow conditions is even conducive to postpone gas gush and decrease gush strength.