The injection of supercritical CO₂ into coal seam alters the mechanical properties of the coal, which should be paid close attention when considering security issues during CO₂-Enhanced CoalBed Methane recovery (CO₂-ECBM). In this study, the Qinshui Basin is considered as the research object, and mechanical parameters, such as the peak strength, elastic modulus, and Poisson's ratio of anthracites under the coupled influences of CO₂ saturation pressure, CO₂ saturation time, and water content were investigated. The results indicate a decrease in the peak strength and elastic modulus and an increase in the Poisson's ratio of the CO₂-saturated coal. Increasing the CO₂ saturation pressure, extending the CO₂ saturation time, and increasing the water content contributes to the softening of the coal. The modified Langmuir equation and stretched exponential (SE) equation are used to accurately predict the peak strength and elastic modulus reduction with CO₂ saturation pressure and CO₂ saturation time, respectively. The failure patterns change from brittle shear failure for natural coal and transitional shear failure for supercritical CO₂-saturated coal to the ductile non-dilatant barreling for the supercritical CO₂+water-saturated coal. The softening effect of coal can be attributed to the chemical and physical reactions between coal and CO₂, including the surface energy reduction of CO₂-bearing coal, extraction and plasticization reactions, differential adsorption swelling and swelling stress, and dissolution of carbonate solution for the mineral filling pore/fracture. In view of the geo-mechanical changes caused by CO₂ to coal, the optimization of the targeted reservoir is pivotal for the successful implementation of CO₂-ECBM.

将超临界CO ₂注入煤层会改变煤的机械性能，在考虑CO ₂增强煤层气回收（CO ₂ -ECBM）期间的安全性问题时应密切注意。本研究以沁水盆地为研究对象，在CO ₂饱和压力，CO ₂饱和时间和含水量的共同影响下，无烟煤的峰值强度，弹性模量和泊松比等力学参数为研究对象。被调查了。结果表明，CO ₂饱和煤的峰值强度和弹性模量降低，泊松比增加。增加CO ₂饱和压力，延长CO ₂饱和时间并增加水含量有助于煤的软化。修改后的Langmuir方程和拉伸指数（SE）方程分别用于精确预测随CO ₂饱和压力和CO ₂饱和时间的峰值强度和弹性模量降低。破坏模式从天然煤的脆性剪切破坏和超临界CO ₂饱和煤的过渡剪切破坏变为超临界CO ₂ +水饱和煤的延性非膨胀桶状破坏。煤的软化作用可以归因于煤与CO ₂之间的化学和物理反应包括降低含CO _2的煤的表面能，萃取和增塑反应，不同的吸附溶胀和溶胀应力，以及用于填充矿物/孔隙的碳酸盐溶液的溶解。考虑到CO ₂对煤造成的地质力学变化，目标油藏的优化对于成功实施CO ₂ -ECBM至关重要。