摘要
CO_(2)致裂技术是一种操作简便、使用环保的煤层增透技术,具有安全、高效以及可以重复使用的优点。为了探究CO_(2)致裂技术在贵州高瓦斯低渗透煤矿的应用效果,选取了贵州两处高瓦斯、低渗透煤矿进行现场实验并观测实验结果。通过检测CO_(2)致裂前后煤层瓦斯宏观参数变化,并进行对比分析,结果表明:CO_(2)致裂技术对煤层增透效果明显,相较于未作用煤层,透气性系数提高了3倍,结合瓦斯自然流量衰减系数,原煤层由较难抽采变为可抽采;瓦斯抽采体积分数、瓦斯抽采纯量均有明显提升,并且致裂后瓦斯抽采纯量在30 d范围内有先增加再降低的趋势,应该是致裂后CO_(2)驱替瓦斯导致;致裂后残余瓦斯含量低于5.5 m^(3)/t,小于原始煤层瓦斯含量,并低于《防治煤与瓦斯突出规定》规定的残余吨煤瓦斯含量临界值8 m^(3)/t。表明CO_(2)致裂技术在增透低渗煤层上具有良好的运用效果。
CO_(2) fracturing technology is an easy and environmental permeability enhancement technology in coal mines with advantages such as safety,efficiency,and reusability.To explore the application effect of CO_(2) fracturing technology in high-gas and low-permeability coal mines in Guizhou,we selected two high-gas and low-permeability coal mines to observe the on-site experimental results.The comparison of the macroscopic parameters of gas before and after CO_(2) fracturing showed that CO_(2) fracturing technology demonstrated a significant effect on enhancing the permeability of coal seams.Compared with untreated coal seams,the gas permeability coefficient has increased by three times;combined with the attenuation coefficient of the natural gas flow,the results showed the transformation from the difficult-extracted coal seams to the extractable coal seams.The gas extraction concentration and pure amount significantly increased by four times,and the pure amount of gas extraction after fracturing tended to increase first and then decrease in the range of 30 d,which could be attributed to the replacement of gas by CO_(2) after fracturing.The residual gas content after fracturing was less than 5.5 m^(3)/t,less than the original gas content,and lower than the critical value(8 m^(3)/t)of residual gas content per ton stipulated in the Provisions on Prevention and Control of Coal and Gas Outburst.The study showed that CO_(2) fracturing technology presented good application effects on permeability enhancement for low-permeability coal seams.
作者
彭鑫
PENG Xin(Guiyang Mineral Energy Investment Group Co.,Ltd.,Guiyang 550014,China)
出处
《山西煤炭》
2024年第1期71-80,共10页
Shanxi Coal
关键词
煤与瓦斯突出
CO_(2)致裂
瓦斯抽采
煤层增透
coal and gas outburst
CO_(2)fracturing
gas extraction
coal seam permeability enhancement
作者简介
彭鑫(1994—),男,贵州贵阳人,硕士,工程师,主要从事瓦斯治理研究,E-mail:18085082532@163.com。
