New surfactant classes for enhanced oil recovery and their tertiary oil recovery potential

We investigate four different types of surfactants for effectiveness in tertiary oil recovery (TOR). The selected surfactant formulations were tested for enhanced oil recovery using coreflood tests on Berea sandstones. In addition to the corefloods, one sandpack surfactant flood was performed. The porous media were conditioned to residual waterflood oil saturation prior to surfactant slug injection. This was followed by polymer drive slug injection, and incremental oil recovery was measured against time.The tested formulations were selected after an extensive research effort including measuring interfacial tensions (IFT) and adsorption behavior on kaolinite clay. Effective were low 1-naphthol concentrations dissolved in 1-butanol in alkyl polyglycoside surfactant formulations which led to significant additional incremental oil recovery (40% TOR) due to dramatic reductions in IFT. Three other types of surfactants in this study include:
• a di-tridecyl sulfosuccinic acid ester,
• coconut diethanolamide, and
• alkylpropoxy sulfate sodium saltswhich led to TOR of 15%, 75% and 35–50%, respectively.These results indicate that a wide variety of surfactants can meet the technical requirements as enhanced oil recovery (EOR) agents.