为了解决传统煤层气开发工艺采收率低的问题,向煤层中注CO2既可以提高采收率,又可以实现CO2地质埋存,减少CO2排放。从CO2物性参数、煤岩微观孔隙特征、煤层渗流规律、煤岩吸附/解析附、煤岩力学稳定性和体积变形等方面,综述了国内外CO2与煤层相互作用的研究进展。针对在井下CO2极易达到超临界状态,结合国内外在CO2气体状态下的研究方法,指出超临界状态的CO2对煤层吸附-渗流-力学-变形性质的耦合影响是未来的研究方向,提出了利用注超临界CO2开发煤层气需要解决的关键问题。
In order to solve the low drainage recovery rate problem of the conventional coalbed methane development technique,the CO2 injection in the seam could improve the drainage recovery rate and could realize the geological deposition of CO2. From the CO2 physical parameters,the micro pore features of the coal and rock,the seepage law of the seam,adsorption and solution of the coal and rock,stability of the coal and rock mechanics,the volume deformation and others,the paper stated the study progress on the interaction between the CO2 and seam at home and abroad. According to the CO2 easy to reach the supercritical state in the underground mine,in combination with the study methods under the CO2 gas state at home and abroad,the paper pointed out that the CO2 in the supercritical state affected to the coupling of the seam adsorption- seepage- mechanics- deformation property would be the future study orientation. The paper provided the key problems to be solved in the coalbed methane development with the application of the supercritical CO2.