Optimizing the development plan for oil production and CO2 storage in target oil reservoir

Carbon dioxide enhanced oil recovery (CO 2 -EOR) technology is used for oil production and CO 2 storage in reservoirs. Methods are being constantly developed to optimize oil recovery and CO 2 storage during the CO 2 displacement process, especially for low-permeability reservoirs under varying geological conditions. In this study, long-core experiments and trans-scale numerical simulations are employed to examine the characteristics of oil production and CO 2 storage. Optimal production parameters for the target reservoir are also proposed. The results indicate that maintaining the pressure at 1.04 to 1.10 times the minimum miscible pressure (MMP) and increasing the injection rate can enhance oil production in the early stage of reservoir development. In contrast, reducing the injection rate at the later stages prevents CO 2 channeling, thus improving oil recovery and CO 2 storage efficiency. A solution-doubling factor is introduced to modify the calculation method for CO 2 storage, increasing its accuracy to approximately 90 %. Before CO 2 breakthrough, prioritizing oil production is recommended to maximize the economic benefits of this process. In the middle stage of CO 2 displacement, decreasing the injection rate optimizes the coordination between oil displacement and CO 2 storage. Further, in the late stage, reduced pressure and injection rates are required as the focus shifts to CO 2 storage. • The micro-mechanisms of CO 2 flooding and sequestration under varying miscibility degrees. • A comprehensive factor for evaluating CO 2 displacement and sequestration effectiveness is proposed. • Refinement of mathematical models for CO 2 displacement and sequestration across different production stages.