Mohammad Simjoo..

In response to growing environmental concerns and increasing global focus on reducing greenhouse gas emissions, Carbon Capture, Utilization, and Storage (CCUS) has emerged as one of the most effective engineering solutions to combat climate change. One of the key methods within this technology is the injection of carbon dioxide (CO₂) into geological formations for long-term storage. However, challenges such as high gas mobility, early breakthrough, uneven flow distribution, and poor performance in heterogeneous porous media have prompted the exploration of complementary methods to improve flow control. Among these, the use of CO₂ foam as a flow control and efficiency-enhancing agent has received significant attention in both research and industrial applications. CO₂-based foam exhibits high viscosity and the ability to drastically reduce gas mobility. This leads to improved flow stability, prevention of preferential flow in high-permeability zones, and enhanced sweep efficiency throughout the reservoir. Furthermore, in multiphase systems containing residual oil, foam can improve displacement efficiency and increase oil recovery, making it a dual-purpose and economically attractive option for integrated CCUS-EOR projects. Findings from laboratory experiments, numerical simulations, and field trials have demonstrated that CO₂ foam can multiply gas storage capacity while simultaneously reducing the risk of CO₂ leakage and unwanted migration. This technology has proven particularly effective in dual-layer systems with permeability contrast, aiding in the optimization of injection processes in complex reservoirs. In summary, the application of foam in CCUS not only enhances gas injection performance at an industrial scale but also facilitates the implementation of safe, stable, and cost-effective storage projects. Further development of this approach requires research into foam stability, optimal formulation design, and comprehensive economic evaluation.

Keywords: CCUS, CO₂ foam, Gas mobility control, Heterogeneous reservoirs, EOR, Subsurface CO₂ Storage.

Co-author/s:

Mohammad Simjoo, Associate Professor, Sahand University of Technology.