Enhancing Oil Recovery with Hydrophilic Polymer-Coated Silica Nanoparticles

Abstract

Nanoparticles (NPs) have been proposed for enhanced oil recovery (EOR). The research has demonstrated marvelous effort to realize the mechanisms of nanoparticles EOR. Nevertheless, gaps still exist in terms of understanding the nanoparticles-driven interactions occurring at fluids and fluid–rock interfaces. Surface-active polymers or other surface additive materials (e.g., surfactants) have shown to be effective in aiding the dispersion stability of NPs, stabilizing emulsions, and reducing the trapping or retention of NPs in porous media. These pre-requisites, together with the interfacial chemistry between the NPs and the reservoir and its constituents, can result in an improved sweep efficiency. This paper investigates four types of polymer-coated silica NPs for the recovery of oil from water-wet Berea sandstones. A series of flooding experiments was carried out with NPs dispersed at 0.1 wt.% in seawater in secondary and tertiary oil recovery modes at ambient conditions. The dynamic interactions of fluids, fluid–rock, and the transport behavior of injected fluid in the presence of NPs were, respectively, studied by interfacial tension (IFT), spontaneous imbibition tests, and a differential pressure analysis. Core flooding results showed an increase in oil recovery up to 14.8% with secondary nanofluid injection compared to 39.7% of the original oil in place (OOIP) from the conventional waterflood. In tertiary mode, nanofluids increased oil recovery up to 9.2% of the OOIP. It was found that no single mechanism could account for the EOR effect with the application of nanoparticles. Instead, the mobilization of oil seemed to occur through a combination of reduced oil/water IFT, change in the rock surface roughness and wettability, and microscopic flow diversion due to clogging of the pores.

Experimental Investigation of Polymer-Coated Silica Nanoparticles for EOR under Harsh Reservoir Conditions of High Temperature and Salinity

“…In addition, the IFT reduction can be due to the surface-active polymer molecules surrounding the surface of the NPs that provide steric repulsive forces and stabilization of the NPs suspension. Comparing the results of the IFT data from previous studies at room temperature [15,17], for the same NPs, the greatest IFT reduction is achieved at elevated temperature. This indicates that the wetting properties and the binding energy of the NPs to the oil/water interface increase with temperature.…”

“…The authors associated the EOR effect to the NPs' ability to decrease the injection pressure; the authors argued that displacement pressure decrease is related to the formation of a wedge film between the oil and the rock surface. More recently, Bila et al [15,16], Bila and Torsaeter [17] carried out a series of flooding experiments with polymer-coated SiO 2 NPs in Berea sandstone core plugs. Their studies revealed an incremental recovery ranging from 2.6% to 14% of the OOIP.…”

Experimental Investigation of Polymer-Coated Silica Nanoparticles for EOR under Harsh Reservoir Conditions of High Temperature and Salinity

“…In addition, www.videleaf.com the IFT reduction can be due to the surface-active polymer molecules surrounding the surface of the NPs that provide steric repulsive forces and stabilization of the NPs suspension. Comparing the results of the IFT data from previous studies at room temperature [15,17], for the same NPs, the greatest IFT reduction is achieved at elevated temperature. This indicates that the wetting properties and the binding energy of the NPs to the oil/water interface increase with temperature.…”

Preparation and properties of modified graphene oxide / polyacrylamide composite nanoparticle gel system

“…Due to the large specific surface area, high temperature, and high salt stability of nanomaterials, nanoparticles have shown unique advantages in oilfield extraction. Polymer-based composite nanoparticle system can enhance temperature, salt and shear resistance due to the presence of inorganic nanoparticles, [12][13][14][15][16][17][18][19] such as silica, nano-alumina, titanium oxide, nickel oxide, and others that can be combined with polymer molecules through hydrogen bonding or other intermolecular forces. 19,20 Meanwhile, the addition of nanoparticles such as silica, [21][22][23][24] carbon nanotubes, 25 and nanoclay 18 can directly affect the viscosity and rheology of the polymer.…”

“…Polymer-based composite nanoparticle system can enhance temperature, salt and shear resistance due to the presence of inorganic nanoparticles, [12][13][14][15][16][17][18][19] such as silica, nano-alumina, titanium oxide, nickel oxide, and others that can be combined with polymer molecules through hydrogen bonding or other intermolecular forces. 19,20 Meanwhile, the addition of nanoparticles such as silica, [21][22][23][24] carbon nanotubes, 25 and nanoclay 18 can directly affect the viscosity and rheology of the polymer. 26 Therefore, combining polymer with nanoparticles to prepare polymer composite nano particle system for profile control and flooding is considered to be one of the effective methods to improve oil recovery of HPAM under high temperature and high salt conditions.…”