Alternate Slugs of Gas and Dilute Surfactant for Mobility Control During Chemical Flooding

TLDR

The study introduces a novel mobility‑control technique for chemical flooding that injects alternating slugs of inert gas and dilute surfactant, offering a potential alternative to polymer‑thickened water. Performance was evaluated in consolidated sandstone and carbonate cores, including large sandstone slabs oriented to maximize gravity segregation of gas. Results show that the gas–surfactant slugs perform comparably to water‑soluble polymers while avoiding disadvantages such as foam drainage and gravity segregation in large sandstone slabs.

Abstract

Abstract Studied was a novel technique for mobility control during chemical flooding, namely, the injection of alternate slugs of inert gas and surfactant solution. This method of reducing mobility offers a possible alternative to polymer thickened water. Performance was investigated in consolidated sandstone and carbonate. Sandstone included cores, and large slabs of rock oriented so as to maximize gravity segregation of gas. Reported data suggest that, for mobility control in laboratory rocks, performance of alternate slugs of gas and dilute surfactant compares favorably with water soluble polymers, without the many disadvantages of the latter. During experiments in large sandstone slabs, excessive foam drainage, and gravity segregation of gas, did not occur.