Enhancing CO_(2) huff-n-puff strategies for improved oil recovery in the Bakken formation: A numerical simulation approachOA

This study investigates the performance of various huff and puff(HnP) strategies for enhanced oil recovery(EOR) in the Sanish field of the Bakken formation, using a numerical model developed with CMG software. The model integrates PVT validation, CO_(2) miscibility, swelling tests, heterogeneity, and history matching with field data. Several HnP strategies, including Supported(S HnP), Alternative Supported(AS HnP), and Alternative Zigzag Supported(AZS HnP), were evaluated. Key findings show that dual porosity and permeability are essential for accurate modeling, while CO_(2) diffusion has minimal impact in field-scale simulations with high fracture spacing. The S HnP strategy improves oil recovery with 50%less CO_(2) than the Normal HnP, and the AS HnP further enhances production. The AZS HnP outperforms both, offering higher oil recovery and better CO_(2) utilization. Fracture length was found to influence recovery significantly, and the sensitivity of oil production to CO_(2) injection rates was notably higher in the AZS HnP compared to the N HnP scenario. These results highlight the potential for optimized CO_(2)-EOR strategies in unconventional reservoirs.