Pore-Scale Assessment of Nanoparticle-Stabilized CO₂ Foam for Enhanced Oil Recovery

Abstract

In this paper, we evaluate nanoparticle-stabilized CO2 foam stability and effectiveness in enhanced oil recovery at the pore and micromodel scales. The nanoparticle-stabilized CO2 gas-in-brine foams maintain excellent stability within microconfined media and continue to be stable after 10 days, as compared to less than 1 day for surfactant foam. The nanoparticle-stabilized CO2 foams are shown to generate a 3-fold increase in oil recovery (an additional 15% initial oil in place), as compared to an otherwise similar CO2 gas flood. Fluorescence imaging is applied to quantify emulsion size distribution (down to 1 μm) in both CO2 and nanoparticle-stabilized CO2 foam flood cases. Nanoparticle-stabilized CO2 foam flooding results in significantly smaller oil-in-water emulsion sizes with an average size of 1.7 μm (∼80% smaller than a CO2 gas flood), with negligible impact on water-in-oil emulsions. The effectiveness of nanoparticle-stabilized CO2 foam is compared for representative light, medium, and heavy oils. All three oils show substantial additional oil recovery and a potentially valuable reservoir homogenization effect. Collectively, these results highlight the pore-scale dynamics, effectiveness, and potential for nanoparticle-stabilized foams in enhanced oil recovery.

Application of Nanoparticles in Enhanced Oil Recovery: A Critical Review of Recent Progress

“…Nguyen et al [137] evaluated NP-stabilized CO2 foam stability and effectiveness in EOR of different types of oils (light, medium and heavy oils) at micromodel scales. All three oils showed substantial additional oil recovery and a potentially valuable reservoir homogenization effect because NP-stabilized CO2 foam flooding resulted in significantly smaller oil-in-water emulsions (Figure 16).…”

The role of condensing and non-condensing solvents in SA-SAGD

“…A closer look in the IR images showed that butane bubbles condensed in the mobile zone, and the condensation of butane bubbles would have brought high flow in this region. The high effectiveness of the C4-SAGD run is thought to be due to the combined effect of bubbles reducing the mobility of the penetrating fluid and reducing the viscous fingering phenomena [32], bubble condensation leading to fast flow in the mobile zone, and the dissolution of butane in bitumen. The pore scale analysis of the C4-SAGD showed a 3.19% recovery improvement over 5 seconds in the captured pore scale region as shown in Fig.…”

Study on a Novel Gelled Foam for Conformance Control in High Temperature and High Salinity Reservoirs

“…Polymer is the most commonly used stabilizer to keep foam stable; however, it is only suitable for low-temperature conditions of no higher than 90 • C because of heat degradation in polymers [30,31]. Nanoparticles are also very popular and effective stabilizers [32][33][34][35]. However, the poor dispersion ability of nanoparticles limits their application in high temperature and high salinity conditions.…”