CO₂ Foam Behavior in Carbonate Rock: Effect of Surfactant Type and Concentration

Abstract

An understanding of how CO 2 foam flows through a reservoir rock is useful for many subsurface applications, including enhanced oil recovery and CO 2 storage. There are economic and environmental benefits in identifying surfactants that exhibit good foaming behavior with CO 2 at both low concentrations and high foam qualities. Core flood experiments have been carried out to investigate the behavior of supercritical CO 2 foams flowing through a high-permeability Indiana Limestone. The foaming behavior and concentration response of two surfactants, a betaine and a sultaine, were investigated. For the two surfactants, the transition foam quality and the maximum apparent foam viscosity both decreased with reducing surfactant concentration. A comparison between the foaming behaviors of these surfactants with CO 2 and N 2 was also carried out. It was found that the N 2 generated stronger foam at low foam qualities, but the CO 2 was better at maintaining good foaming behavior at high foam qualities.

An experimental study of foam-oil interactions for nonionic-based binary surfactant systems under high salinity conditions

“…When carefully screened and combined, binary surfactant systems have the ability to enhance foaming behavior and stability through synergistic effects, such as increasing solubility, lowering the critical micelle concentration, and improving film elasticity. Jones et al 13 asserted that foams generated with binary surfactants tend to have faster foam propagation, higher apparent foam viscosity, and better performance than foams generated with single surfactants because of their enhanced solubility, mobility control, and film stability. By mixing two different surfactants, the solubility of the resulting mixture in both CO 2 and water can be increased, which can improve foam generation and stability 4 .…”

Interfacial properties and foam performance of alpha olefin sulfonate and CO2 switchable aminopropyl methyl siloxane surfactant mixtures

“…Foam properties are normally characterized by the initial height (foamability) and the height loss over time (foam stability) (Li et al, 2021). A great deal of research on the factors affecting foamability has been done, among which the types and structures of the surfactants, interfacial tension (IFT), and electrostatic charges are considered as the key ones (Alexander et al, 2022; Jones et al, 2022). As for foam stability, three main foam destabilization processes will have a negative impact, including liquid drainage (Zhan et al, 2022), bubble Ostwald ripening (also known as “bubble coarsening”) and bubble coalescence with other bubbles or with atmosphere (Zhou et al, 2020).…”