CO₂ Foam and CO₂ Polymer Enhanced Foam for Heavy Oil Recovery and CO₂ Storage

• Main Authors: Ali Telmadarreie, Japan J Trivedi
• Format: Article
• Language: English
• Published: MDPI AG 2020-11-01
• Series: Energies
• Subjects: CO₂ foam; polymer enhanced foam; heavy oil recovery; CO₂ storage; fractured reservoir
• Online Access: https://www.mdpi.com/1996-1073/13/21/5735

Enhanced oil recovery (EOR) from heavy oil reservoirs is challenging. High oil viscosity, high mobility ratio, inadequate sweep, and reservoir heterogeneity adds more challenges and severe difficulties during any EOR method. Foam injection showed potential as an EOR method for challenging and heterogeneous reservoirs containing light oil. However, the foams and especially polymer enhanced foams (PEF) for heavy oil recovery have been less studied. This study aims to evaluate the performance of CO₂ foam and CO₂ PEF for heavy oil recovery and CO₂ storage by analyzing flow through porous media pressure profile, oil recovery, and CO₂ gas production. Foam bulk stability tests showed higher stability of PEF compared to that of surfactant-based foam both in the absence and presence of heavy crude oil. The addition of polymer to surfactant-based foam significantly improved its dynamic stability during foam flow experiments. CO₂ PEF propagated faster with higher apparent viscosity and resulted in more oil recovery compared to that of CO₂ foam injection. The visual observation of glass column demonstrated stable frontal displacement and higher sweep efficiency of PEF compared to that of conventional foam. In the fractured rock sample, additional heavy oil recovery was obtained by liquid diversion into the matrix area rather than gas diversion. Aside from oil production, the higher stability of PEF resulted in more gas storage compared to conventional foam. This study shows that CO₂ PEF could significantly improve heavy oil recovery and CO₂ storage.