Experimental Study of the Stabilization of CO₂ Foam by Sodium Dodecyl Sulfate and Hydrophobic Nanoparticles

Abstract

CO2 foam can control the CO2 mobility and improve the sweep efficiency in reservoirs; however, CO2 foam stabilized solely by surfactants is not stable. Nanoparticles can improve the performance of CO2 foam. The synergistic effect of SiO2 nanoparticles and sodium dodecyl sulfate (SDS) on the CO2 foam stability was studied in this paper. The experimental results show that the synergistic effect requires an SDS/SiO2 concentration ratio of 0.1–0.4. The strength of the effect increases as the SDS/SiO2 concentration ratio increases from 0.1 to 0.17 but then decreases as the ratio further increases from 0.17 to 0.4; thus, a ratio of 0.17 provides the best performance for CO2 foam. The mechanisms of the synergistic effect of SDS and SiO2 include modulating the position of nanoparticle adsorption on the CO2 and liquid interface, improving the interfacial properties of the CO2 foam, and reducing its liquid discharge and coarsening. SiO2 nanoparticles can also improve the CO2 foam performance under high temperatures and pressures. The visual flooding experiment reveals that the addition of SiO2 nanoparticles can improve the stability of CO2 foam in porous media and shows good tolerance of crude oil. SDS/SiO2 foam can increase the pressure differences of the flow in sandpacks after water flooding and improve the oil recoveries markedly. As the SDS/SiO2 concentration ratio increases, the pressure differences and enhanced oil recovery first increase and then decrease. The best CO2 foam flooding performance is achieved at an SDS/SiO2 concentration ratio of 0.17, which is related to the CO2 foam stability. The experimental results provide theoretical support for improving CO2 foam flooding under reservoir conditions.

Experimental study on stability and rheological properties of aqueous foam in the presence of reservoir natural solid particles

“…Concentration of solid particles in liquid phase, their wettability, size and shape are critical parameters affecting bulk foam stability [28][29][30][31][32][33][34][35][36][37][38][39]. Concentration of solid particles defines the quantity of particle association in foam lamellae and at the plateau borders, which is a key factor for apparent viscosity enhancement of bulk foam [38][39][40][41][42].…”

“…Nowadays, silica and metal nanoparticles are frequently used as a foam stabiliser agent for enhanced oil recovery processes [38,39,41,47]. It was found that nanoparticles at concentrations between 0.05 -2 wt% can stabilise foam in the presence of both non-ionic and anionic surfactants.…”

“…It was found that nanoparticles at concentrations between 0.05 -2 wt% can stabilise foam in the presence of both non-ionic and anionic surfactants. These types of nanoparticle foam are two to eighteen times more stable compared to the same foam without nanoparticles in its structure [34,38,39,41,47]. Properties and performance of particle-stabilised foam have been investigated by many researchers [30-33, 36-40, 42, 43, 47-50].…”

Hydraulic Properties of Porous Media Saturated with Nanoparticle-Stabilized Air-Water Foam

“…The specific gravity was 2.65. The effective diameter D 10 , D 30 , and D 60 were 0.27 mm, 0.35 mm, and 0.46 mm, respectively. The coefficient of uniformity was C u = 1.66, and coefficient of curvature was C c = 0.98.…”

Experimental study on controlled-release inhibitor foam for restraining spontaneous combustion of coal

“…With the loss of water, their inhibition efficiency is greatly decreased (Li et al, 2012b). In maintaining the high efficiency of inhibiting spontaneous coal combustion, the application of temperature sensitive materials as coating to allow the release of inhibitors at a specific temperature was investigated (Cui et al, 2017;Li et al, 2016a;Ma et al, 2016Ma et al, , 2017Qi et al, 2016). However, they did not consider the effect of diffusion and action range of inhibitors, and it was found that the covered area of coal was extremely limited after solid or liquid inhibitors were released.…”