Upscaling CO2 Foam for EOR as CCUS from On- To Offshore

Abstract

Two major challenges in CO2 enhanced oil recovery (EOR) are the high mobility of CO2 and reservoir heterogeneity. High CO2 mobility, related to the low density and viscosity of CO2, compared to in-situ fluids can cause viscous fingering, gravity override, and flow in thief zones resulting in poor reservoir sweep efficiency and low oil recoveries. Mobility control foam can improve CO2 EOR and CO2 storage potential by mitigating unfavorable CO2 properties and reducing the impact of reservoir heterogeneity. CO2 foam injection involves injecting a foaming agent (surfactant) with CO2 to generate stable foams in porous media. This work presents an incremental physical upscaling approach that moves from the pore- to core- to field-scale for characterizing and optimizing foam systems for CO2 mobility control, EOR, and CO2 storage. An additional focus was to visualize and describe in-situ fluid saturation dynamics during CO2 storage processes. We address the challenges associated with transferring CO2 foam EOR technology offshore, using lessons learned from an ongoing onshore pilot in the Permian Basin of west Texas. The aim is to encourage co-optimized CO2 EOR and long-term CO2 storage foam technology as part of carbon capture, utilization, and storage (CCUS) for offshore applications.