Synergistic Mechanism of CO₂ and Liquid Phase De-Blocking Agent and Their Performance of Carbon Storage in Condensate Gas Reservoirs

The effects of injecting CO₂, liquid phase de-blocking agents, and CO₂-dissolved liquid phase de-blocking agents on the removal of condensate and water block pollution in condensate gas reservoirs were investigated. The research emphasized the mechanisms of synergistic de-blocking and carbon storage involving CO₂ and li-quid phase de-blocking agents in these reservoirs. The results show that under conditions of 12 MPa and 100 ℃, CO₂ is not miscible with condensate oil, resulting in a permeability recovery rate of 30.54% in reservoir pollution removal experiments. In contrast, when CO₂ is dissolved in a liquid phase de-blocking agent, the permeability recovery rate significantly increases to 74.38%, demonstrating enhanced de-blocking effectiveness. In the process of CO₂ injection for de-blocking, the CO₂ storage rate is 92.75%; however, when using CO₂-dissolved liquid phase de-blocking agents, the CO₂ storage rate reaches 98.47%. During the mass transfer of CO₂, it can dissolve in formation water and condensate oil, facilitating carbon storage. The CO₂-dissolved liquid phase de-blocking agent combines the advantages of CO₂ and chemical de-blocking agents, significantly improving de-blocking effectiveness while also enabling effective CO₂ storage. This approach addresses the need for enhanced gas recovery and carbon neutrality. The results of the research provide new technical perspective for the efficient development of condensate gas reservoirs.