Hydrogen foam flooding for integrated oil recovery and clean energy storage in depleted reservoirs

Within the broader strategy of deep decarbonization, hydrogen stands out as an emerging energy vector poised to influence various sectors. Recognizing that its role is in development and not yet fully realized, our research focuses on the transitional use of depleted oil reservoirs for hydrogen storage and enhanced oil recovery (EOR). While these reservoirs are not geologically superior for hydrogen storage, their established containment capabilities and existing infrastructure offer dual benefits and economic incentives through the valorization of residual oil. To circumvent the limitations of conventional hydrogen injection, such as poor sweep efficiency and premature breakthrough, we propose the use of high-viscosity hydrogen foam. Our experimental data reveals that such foam can significantly enhance oil recovery by 17.95% and increase storage efficiency to 36.2%. These improvements underscore the foam's ability to control hydrogen mobility and optimize sweep efficiency within heterogeneous geological formations. These findings suggest that high-viscosity hydrogen foam could significantly improve the effectiveness of depleted reservoirs for both energy storage and the recovery of residual oil. Looking forward, it is crucial to investigate the long-term integrity of subsurface hydrogen storage, the transition from laboratory to field-scale applications, and the environmental consequences to ensure that this approach is sustainable. Our study serves as an incremental step in recognizing the integral role hydrogen could play in achieving a decarbonized energy future.