王家岭煤矿CO_2相变致裂煤层增透技术应用研究

Application Research of CO_2 Phase Change Crack Technology on Permeability Enhancements of Coal Seam in Wangjialing Coal Mine

针对王家岭煤矿2^#煤层低透气性的特点，采用CO2相变致裂技术进行煤层增透现场实验研究，现场测试得出爆破深度在27～30m内，当爆破孔与控制孔间距1．5m时，单孔CH。抽采纯量和浓度分别提高至6倍和5倍，160min后CH。浓度衰减明显；当爆破孔与控制孔间距2．5m时，单孔CH4抽采纯量和浓度分别提高至4倍，120min后CH4浓度衰减明显。说明在30m爆破范围内，对于王家岭煤矿低透气性煤层CO2爆破短时间抽采效果明显。

In the light of the characteristics of low permeability of 2^# coal seam in Wangjialing coal mine,and according to on-site experiment research of the coal seem C02 phase change crack,it has been found distance to that when the blasting depth is in the range of 27-30 meters,and the control hole 1.5 m the blasting hole, the CH4 extraction and concentration in single control hole were increased to 6 and 5 times, respectively,and the CH4 extraction effect attenuate obviously after 160 minutes.When the control hole 2.5 m distance to the blasting hole,the CH4 extraction and concentration in single control hole were increased to 4 times, respectively, and the CH4 extraction effect attenuate obviously after 120 minutes. The result shows that in the range of 30 meters the pumping effect of carbon dioxide explosion in low permeability coal seam is obvious in short time.