基于低透气性煤层的二氧化碳爆破增透技术试验研究

Experimental study on CO_2 antireflective blasting technology based on low breathability of coal seam

为考察利用二氧化碳爆破增透技术对低透气性煤层瓦斯抽采效果的影响,采用理论分析研究了二氧化碳爆破增透技术对低透气性煤层的增透原理,并在20321工作面回风巷道进行了二氧化碳增透技术试验,对比分析了爆破孔间距分别为2 m和3 m时与爆破前的增透效果。试验表明,距离2m处的抽采孔瓦斯抽采浓度提高至5倍,抽采纯量提高至6倍,160min后瓦斯浓度衰减明显;距离3m处抽采孔瓦斯抽采浓度提高至4倍,抽采纯量提高至4倍,120min后瓦斯浓度衰减明显。

In order to study the influences of CO2 antireflective blasting technology on gas extraction effects in low-breathability coal seam,the antireflective theory of the CO2 antireflective blasting technology was studied by using theoretical analysis method,and the test was conducted in return airway of 20321 working face,which contrastively analyzed the antireflective effects before and after the blasting,and analyzed the differences when the pitch of holes was 2 mand 3 mrespectively.The test results showed that when the pitch of holes was 2 mand,the gas extraction concentration in holes was increased by 4 times and the extraction quantity was increased by 5 times,after 160 minutes,the gas concentration decreased obviously;while the pitch of holes was 3 m,the gas extraction concentration in holes was increased by 3 times and the extraction quantity was increased by 3 times,after 120 minutes the gas concentration decreased obviously.