Interfacial Rheology of Foam Stabilized by Nanoparticles and Their Retention in Porous Media
Qian Sun, Wei Liu, Songyan Li, Na Zhang, Zhaomin Li
Abstract
Nanoparticle-stabilized foam has aroused people’s attention due to its wide applications in oil fields. Understanding the dynamic surface properties of nanoparticles and their retention in reservoir formation is crucial for their application. This research presents the impact of mixing SiO2 nanoparticles and sodium dodecyl sulfate (SDS) on foaming and interfacial properties. Also, the retention behaviors of nanoparticles in sandpacks with different permeabilities are discussed by employing the core-flooding apparatus. The experimental results show that nanoparticles and SDS exhibit synergy on foam stability, although the foam volume decreases in the presence of nanoparticles. It is inferred that SDS may determine the equilibrium surface pressure of the mixed system, as the nanoparticles can affect the surface pressure slightly. There exists a competitive behavior between SDS and nanoparticles during adsorption, and the presence of nanoparticles lowers the adsorption rate of the mixing system. The film behaves more elastic for SiO2/SDS dispersion as the dilatational elasticity of the dispersion is enhanced in the presence of nanoparticles, while the dilatational viscosity changes little. In the retention experiments, nanoparticles can flow through the sandpack smoothly due to their nanometer sizes with few changes on the sandpack permeability. The nanoparticle retention decreases with increasing the sandpack permeability, and it is possible to reinject the recovered nanoparticles into the formation by comparing the foam properties before and after sandpack injection. We hope this research may guide the further application of nanoparticle-stabilized foam in oil fields.