The invention discloses a method for improving the extraction rate of a high residual gas content
coal seam of an underground
coal mine. The method comprises the following steps that a mounting hole is drilled; a hole opening sealing connection
pipe fitting is mounted and fixed; construction of a gas extraction
drill hole is conducted; CaC2 is stored in the gas extraction
drill hole; a mine waterpressing pipeline is connected with the hole opening sealing connection
pipe fitting, water is jetted into the gas extraction
drill hole, and the hole opening sealing connection
pipe fitting is closedafter jet is finished; CaC2 in the gas extraction
drill hole and the water are subjected to reaction to generate Ca(OH)2 and C2H2, a large amount of heat is generated at the same time, under the
thermal effect,
coal seam gas is accelerated to conduct desorbing; and the hole opening sealing connection
pipe fitting is connected with an extraction pipe, and gas extraction is conducted through pipe-linking. According to the method for improving the extraction rate of the high residual gas content coal seam of the underground coal mine, the temperature in the
drill hole is further improved to promote gas
desorption of the coal seam, and the gas extraction rate is improved accordingly; and interval hole drilling implement or concentrated hole drilling implement can be adopted according to occurrence characteristics of the coal seam and the
drill hole arranging form. The method for improving the extraction rate of the high residual gas content coal seam of the underground coal mine has the characteristics of safety, high efficiency, reliability and small
engineering quantity, and can be widely used in the field of gas extraction of the underground coal mine.