Shaanxi Binchang Xiaozhuang Mining Industry Co., Ltd.
College of Safety Science and Engineering, Xi'an University of Science and Technology

煤层瓦斯抽采效率不足是高瓦斯及突出矿井采掘接续困难和瓦斯事故频发的主要原因,为了提高煤层采前瓦斯预抽效率,降低矿井瓦斯灾害治理成本,基于液态二氧化碳对煤层进行低温致裂增透和对煤层瓦斯进行相变交换置换驱替的两方面影响,针对彬长小庄煤矿低透气性、瓦斯难以抽采的问题,以40205工作面为研究对象,通过对其进行液态二氧化碳驱替煤层气技术深入分析和工程应用,分析了现场抽采效果。现场应用表明,驱替后的钻孔内瓦斯浓度平均增加1.425倍,纯量平均增加1.33倍,瓦斯抽采效率明显提升。该结果初步证实了液态二氧化碳驱替技术的适用性,为煤矿瓦斯抽采提供了一定的技术支撑。

The insufficient efficiency of coal seam gas extraction is the main reason for the difficulty in continuous mining and excavation and frequent occurence of gas accidents in high gas and outburst mines. In order to improve the gas pre extraction efficiency of coal seams before mining and reduce the governance costs of mine gas disasters, based on the influence caused by liquid carbon dioxide of two aspects of low-temperature fracturing and permeability enhancement of coal seams and phase change exchange substitution displacement of coal seam gas, aiming at the problems of low permeability and difficult gas extraction in Binchang Xiaozhuang Coal Mine, taking the 40205 working face as the research object, the on-site extraction effect is analyzed through in-depth analysis and engineering application of liquid carbon dioxide displacement coalbed methane technology. The on-site application shows that the average gas concentration in the borehole after displacement increases by 1.425 times, and the average pure quantity increases by 1.33 times, indicating a significant improvement in gas extraction efficiency. This result preliminarily confirms the applicability of liquid carbon dioxide displacement technology and provides certain technical support for coal mine gas extraction.