Evaluating the potential of surface-modified silica nanoparticles using internal olefin sulfonate for enhanced oil recovery

Abstract

Recently, nanoparticles have proven to enhance oil recovery on the core-flood scale in challenging high-pressure high-temperature reservoirs. Nanomaterials generally appear to improve oil production through wettability alteration and reduction in interfacial tension between oil and water phases. Besides, they are environmentally friendly and cost-effective enhanced oil recovery techniques. Studying the rheological properties of nanoparticles is critical for field applications. The instability of nanoparticle dispersion due to aggregation is considered as an unfavorable phenomenon in nanofluid flooding while conducting an EOR process. In this study, wettability behavior and rheological properties of surface-treated silica nanoparticles using internal olefins sulfonates (IOS 20-24 and IOS 19-23), anionic surfactants were investigated. Surface modification effect on the stability of the colloidal solution in porous media and oil recovery was inspected. The rheology of pure and surfacetreated silica nanoparticles was investigated using a HPHT rheometer. Morphology and particle size distributions of pure and coated silica nanoparticles were studied using a field emission scanning electron microscope. A series of core-flood runs was conducted to evaluate the oil recovery factor. The coated silica nanoparticles were found to alter rheological properties and exhibited a shear-thinning behavior as the stability of the coated silica nanoparticles could be improved considerably. At low shear rates, the viscosity slightly increases, and the opposite happens at higher shear rates. Furthermore, the surfacemodified silica nanoparticles were found to alter the wettability of the aqueous phase into strongly water-wet by changing the contact angle from 80° to 3° measured against glass slides representing sandstone rocks. Oil-water IFT results showed that the surface treatment by surfactant lowered the oil-water IFT by 30%. Also, the viscosity of brine increased from 0.001 to 0.008 Pa s by introducing SiO 2 nanoparticles to the aqueous phase for better displacement efficiency during chemicalassisted EOR. The core-flood experiments revealed that the ultimate oil recovery is increased by approximately 13% with a surfactant-coated silica nanofluid flood after the conventional waterflooding that proves the potential of smart nanofluids for enhancing oil recovery. The experimental results imply that the use of surfactant-coated nanoparticles in tertiary oil recovery could facilitate the displacement efficiency, alter the wettability toward more water-wet and avoid viscous fingering for stable flood front and additional oil recovery.

Wettability Changes Due to Nanomaterials and Alkali—A Proposed Formulation for EOR

“…Sharma et al [ 16 ] observed that IFT was reduced in a brine/oil system by almost half of the initial, after adding 1 wt.% of SiNPs. Ahmed et al [ 17 ] reported that IFT in an oil/brine system decreased by three times its original value after surface-treated SiNPs were added to the brine. They observed that IFT reduction was more significant when the concentration of NPs was increased.…”

Numerical simulation of enhanced oil recovery studies for aqueous gemini surfactant‐polymer‐nanoparticle systems

“…The critical NP concentration obtained in case of surfactant‐polymer‐nanoparticle (SPN) fluids is lower (0.025 wt.%) as compared to that obtained for surfactant fluids (0.030 wt.%). Beyond this limit, IFT was observed to increase gradually owing to improved steric effect in the presence of higher concentration species 59,60 . This indicated desorption of interacting molecules/particles from the interface to the bulk solution phase and consequent transition of mixed micelles to super micelles or vesicles 59,60 .…”

“…Beyond this limit, IFT was observed to increase gradually owing to improved steric effect in the presence of higher concentration species 59,60 . This indicated desorption of interacting molecules/particles from the interface to the bulk solution phase and consequent transition of mixed micelles to super micelles or vesicles 59,60 . SPN fluids are able to recover oil with IFT values in the desired optimal range and sweep crude oil with greater efficacy as compared to surfactant‐nanoparticle and surfactant formulations.…”

Hybrid Application of Nanoparticles and Polymer in Enhanced Oil Recovery Processes

“…The contact angle is an influential parameter for determining wettability alteration, relative permeability curves, and capillary pressure. These parameters have significantly affected the oil recovery performances, as they has been affected by the water–wet or oil–wet property between rock surface and fluid [ 76 , 77 ]. The contact angles were measured for polymer and water treatment on the surface area in the presence of various nanoparticles concentrations (SiO 2 nanoparticle).…”