To further improve carbon dioxide enhanced oil recovery CO₂-EOR efficiency in heterogeneous reservoirs, the use of CO₂ microbubbles as a temporary blocking agent is attracting widespread interest due to their significant stability. This study aims to investigate the plugging performance of CO₂ microbubbles in both homogeneous and heterogeneous porous media through a series of sandpack experiments. First of all, CO₂ microbubble fluids were generated by stirring CO₂ gas diffused into polymer (Xanthan gum (XG)) and surfactant (Sodium dodecyl sulfate (SDS)) solution with different gas: liquid ratios. Then, CO₂ microbubbles fluids were injected into single-core and dual-core sandpack systems. The results show that the rheological behaviors of CO₂ microbubble fluids in this study were followed the Power-law model at room temperature. The apparent viscosity of CO₂ microbubble fluid increased as the gas: liquid ratio increased. CO₂ microbubbles could block pore throat due to the “Jamin effect” and increase the resistance in porous media. The blocking ability of CO₂ microbubbles reached an optimal value at the gas:liquid ratio of 20% in the homogeneous porous media. Moreover, the selective pugging ability of CO₂ microbubbles in dual-core sandpack tests was significant. CO₂ microbubbles exhibited a good flow control profile in the high permeability region and flexibility to flow over the pore constrictions in the low permeability region, leading to an ultimate fractional flow proportion (50%:50%) in the dual-core sandpack model with a permeability differential of 1.0:2.0 darcy. The fractional flow ratio was considerable compared with a polymer injection. At the higher heterogeneity of porous media (0.5:2.0 darcy), CO₂ microbubble fluid could still establish a good swept performance. This makes CO₂ microbubble fluid injection a promising candidate for heterogeneous reservoirs where conventional CO₂ flooding processes have limited ability. This finding would be helpful in developing the utilization of CO₂ microbubbles in EOR operation by better understanding their plugging mechanism in porous media.

为了进一步提高非均质油藏中二氧化碳提高采收率的CO ₂ -EOR效率，使用CO ₂微泡作为临时封堵剂因其显着的稳定性而受到广泛关注。本研究旨在通过一系列填砂实验研究CO _{2微泡在均质和非均质多孔介质中的堵塞性能。}首先，通过搅拌扩散到不同气液比的聚合物（黄原胶（XG））和表面活性剂（十二烷基硫酸钠（SDS））溶液中的CO _{2气体，生成CO 2微泡流体。}那么，CO ₂微泡流体被注入单核和双核砂包系统。结果表明，本研究中CO ₂微泡流体在室温下的流变行为遵循幂律模型。CO ₂微泡流体的表观粘度随着气液比的增加而增加。CO ₂微泡由于“贾敏效应”而堵塞孔喉，增加了多孔介质的阻力。在均质多孔介质中，气液比为20%时CO ₂微泡的阻隔能力达到最佳值。_{此外，CO 2}微泡在双芯砂包试验中的选择性堵塞能力显着。二氧化碳₂微气泡在高渗透区表现出良好的流动控制剖面和在低渗透区流过孔隙收缩的灵活性，导致具有渗透率的双芯砂包模型中的最终分流比例（50%:50%） 1.0:2.0 达西之差。与聚合物注入相比，分流比相当大。在多孔介质非均质性较高（0.5:2.0 darcy）下，CO ₂微泡流体仍能建立良好的波及性能。这使得CO _{2微泡流体注入成为常规CO 2}驱油过程能力有限的非均质油藏的有希望的候选者。这一发现将有助于开发 CO _2的利用通过更好地了解其在多孔介质中的堵塞机制，提高采收率作业中的微气泡。