Effect of microemulsion on foam stability

Abstract

Microemulsion-foam interactions are significant in the low tension gas process, an emerging enhanced oil recovery method. As oil-water-surfactant systems are subjected to various salinity environments and microemulsion phase behavior varies, foam strength has also been observed to vary. This may be due to the action of oil-swollen micelles within liquid lamellae. Winsor Type I microemulsions were characterized according to surface tension, oil content, oil-swollen micelle size, and viscosity. Their impact on foam stability was quantified via dynamic Bikerman-style glass column tests and static decay tests in a physical rock network microfluidic chip to observe behavior and trends across scales. Foam stability tests demonstrated up to 90% decrease in stability with similar trends at both scales as oil-swollen micelle diameter increased from 9.30 to 27.08 nm and concentration decreased over 80%. Decrease in micelle availability and micellar structuring effectiveness, with interaction effects, explains the impact of microemulsion on foam stability.