Abstract:
The effects of injecting CO
2, liquid phase de-blocking agents, and CO
2-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 CO
2 and li-quid phase de-blocking agents in these reservoirs. The results show that under conditions of 12 MPa and 100 ℃, CO
2 is not miscible with condensate oil, resulting in a permeability recovery rate of 30.54% in reservoir pollution removal experiments. In contrast, when CO
2 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 CO
2 injection for de-blocking, the CO
2 storage rate is 92.75%; however, when using CO
2-dissolved liquid phase de-blocking agents, the CO
2 storage rate reaches 98.47%. During the mass transfer of CO
2, it can dissolve in formation water and condensate oil, facilitating carbon storage. The CO
2-dissolved liquid phase de-blocking agent combines the advantages of CO
2 and chemical de-blocking agents, significantly improving de-blocking effectiveness while also enabling effective CO
2 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.