Several benefits of CO₂ injection are reported in the literature such as its ability to mitigate greenhouse gas emissions and the increase in oil recovery at a low cost. However, the correlated reservoir-engineering problems with low-temperature CO₂ injection including formation damage and leakage risk are still uncertain and has not been comprehensively investigated. This research examines the effect of low-temperature CO₂ on lowering of formation breakdown pressure, and the associated formation damage from a geomechanical prospective. This study presents the coupling of the equilibrium stress equation, the system energy balance equation, continuity equation, and saturation equation to develop thermoporoelastic model for the reservoir rock. We determined the cooling-induced formation damage due to decrease in temperature and thermal stresses, formation contraction and tensile stresses, and examine its effects on formation properties, stresses, joint and fracture stability. We observed that low-temperature CO₂ would create a low thermal stress region and thus the formation could fail in tension. This process might increase formation permeability but it would decrease the stability of reservoir, basement and caprock. We analyzed several factors affecting formation deformation such as injection rate for both miscible and immiscible CO₂ flooding, formation porosity, depth, temperature, and formation breakdown pressure. We also compared our results and findings with experimental data, finding excellent match and similar consequences. Furthermore, as a sequence of low-temperature CO₂ injection, the initial formation breakdown pressure was initially at 2560 psi and it reduced to 1928 for immiscible case and 1270 psi for miscible case in the selected case study. We also propose that shallow reservoirs should be avoided for CO₂ capture and storage because of stability issues.

文献中报道了注入CO _2的若干好处，例如其减轻温室气体排放的能力以及以低成本增加石油采收率。然而，与低温CO ₂注入相关的储层工程问题，包括地层破坏和泄漏风险仍然不确定，因此尚未进行全面研究。这项研究考察了低温CO _2的影响降低地层击穿压力，以及地质力学前景对地层造成的损害。本研究提出了平衡应力方程，系统能量平衡方程，连续性方程和饱和度方程的耦合，以开发储层岩石的热孔隙弹性模型。我们确定了由于温度和热应力，地层收缩和拉伸应力降低而导致的冷却引起的地层损伤，并研究了其对地层性质，应力，接缝和断裂稳定性的影响。我们观察到低温CO ₂会产生低的热应力区域，因此地层可能无法拉伸。这个过程可能会增加地层渗透率，但会降低储层，基底和盖层的稳定性。我们分析了几种影响地层变形的因素，例如可混溶和不可混溶的CO ₂驱注入速率，地层孔隙度，深度，温度和地层破裂压力。我们还将我们的结果和发现与实验数据进行了比较，发现了出色的匹配结果和相似的结果。此外，作为低温CO ₂的顺序注入时，初始地层破裂压力最初为2560 psi，在选定的案例研究中，对于不混溶的情况，降低至1928 psi；对于混溶的情况，降低至1270 psi。我们还建议，由于稳定性问题，应避免将浅层储层用于CO _2的捕集和封存。