Experimental Investigation and Modeling of a Nanoparticle-Based Foam: Core Scale Performance for Enhanced Oil Recovery

Abstract

Abstract Nanoparticle-based foam shows promise to enhance oil recovery; however, there is limited experimental investigation on the influence of injection sequence on recovery. The objective of the present study is to systematically compare the injection sequence of SiO2 nanoparticle-based foam, viz, brine-gas-foam-gas (N2) and brine-foam-brine, using core flooding experimental and simulation analyses. Relative permeability endpoints and Corey exponents are found by history matching the experimental production data using a commercial software. To match foam parameters and assess recovery considering underlying physics a software was used. Three coreflooding experiments using a novel nanoparticle-based foam were conducted on two unaged and one aged sandstone cores to investigate two injection sequences (i.e., water (brine)-gas-foam-gas and water-foam-water) at reservoir conditions. The stability and solubility of the nanofoam were studied in high-pressure and high-temperature interfacial tension experiments. Experimental results indicate that the water (brine)-gas-foam-gas sequence results in higher recovery at core scale with a 13.2% increase in recovery after foam injection and total recovery of 80.2% after respective injections of 2.0, 1.8, 1.2 and 0.5 PV of water-gas-foam-gas. The water-foam-water sequence results in a 4.4% increase in recovery after foam injection and total recovery of 61.6% after respective injections of 0.9, 2.9 and 2 PVs in water-wet core and a 6.6% increase after foam injection and total recovery of 73.3% after respective injections of 1.2, 0.6, and 0.6 PV (brine-foam-brine) in an oil-wet core. Increased oil recovery in all experiments ranged from 6.6 to 30.6%. Unlike previous studies, we investigate different nanofoam injection sequences in different wetting condition (aged/unaged cores). A limited number of studies for nanofoam on highly permeable sandstones (500–750 mD) have been reported. Results of this study show that the generated nanoparticle-based foam can be used to favorably control mobility and enhance oil recovery. The numerical simulation efforts led to several critical learnings on the physics of incremental oil recovery from dry-out effects of the foam, as well as the limitations of current commercial simulators in properly replicating the entire physics.