Xintian Coal Mine, Yonggui Energy Development Co., Ltd.

水射流措施往往在煤层增透上有着良好效果,但是不同的水射流措施所取得的效果各不相同。为解决常规不同水射流对煤层的破坏机理,采用相同水压的脉冲水射流和水力冲孔这两种不同水射流措施在贵州新田煤矿9#煤层上进行试验。试验结果表明,随着水压稳定在20MPa时,水力冲孔措施所冲出煤量大于脉冲射流措施所冲出的煤量,并且水力冲孔煤块为微粒形煤块,脉冲射流所冲出的煤块为大块样煤块。脉冲射流的单孔瓦斯流量较水力冲孔的单孔瓦斯流量增长了1.18倍,瓦斯浓度较水力冲孔的增长了13.46%,对于出煤量少的现象是脉冲射流对煤表面呈现出裂纹细密且规则的破碎效果,水力冲孔对煤表面呈现出破碎效果,裂纹混乱且无规律。

Water jet measures often have good effects on enhancing coal seam permeability, but the effects achieved by different water jet measures vary. To solve the failure mechanism of conventional different water jets on coal seams, two different water jet measures, pulse water jet and hydraulic punching with the same water pressure, are tested on the coal seam of Xintian Coal Mine in Guizhou. The experimental results show that as the water pressure stabilizes at 20 MPa, the amount of coal punched out by hydraulic punching measure is greater than that punched out by pulse jet measure, and the coal blocks punched out by hydraulic punching are in the form of fine particles, while the coal blocks punched out by pulse jet are in the form of large block sample. The single hole gas flow rate of pulse jet is 1.18 times higher than that of hydraulic punching, and the gas concentration is 13.46% higher than that of hydraulic punching. For the phenomenon of small coal output, the pulse jet presents a fine and regular crack crushing effect on the coal surface, while hydraulic punching presents a chaotic and irregular crack crushing effect on the coal surface.