Di-Alkyl Chain Surfactants as a Main Surfactant for Enhancing Oil Recovery for Tight Oil Formations

Abstract

Some reservoirs have tight oil formations, such as the Changqing reservoir. The surfactant polymer flooding and low-tension gas flooding are two potential chemical flooding methods for use in tight oil formations. In these methods, an oil displacement agent, or surfactant, is added. Derivatives of nonionic surfactants with extended chains (by propylene oxide and ethylene oxide) from di-alkyl alcohols were developed and tested. A synergistic blend of surfactants was developed between the di-alkyl chain surfactants and anionic surfactants that lowers interfacial tension and improves surfactant solubility in high salinity water and oil.

Dependencies are inferred from the claim text.