A Strategy for Low Cost, Effective Surfactant Injection

Abstract Ideally, in a chemical flooding process, one would like to inject a surfactant solution that has good solubility at the relevant conditions, ultralow interfacial tension (efficient oil mobilisation) and low loss of surfactant (better economics) in the porous medium. The key question is – can you have low loss of surfactant, i.e. low retention, at ultralow interfacial tension? To answer this question, we have undertaken a systematic study of surfactant solubility, phase behaviour, interfacial tension and retention as a function of salinity for a given surfactant formulation. The idea is to explore the interrelationship between these properties and find the best condition(s) for combined low interfacial tension and low retention in a surfactant flooding process. For the investigated surfactant formulation, ultra-low interfacial tensions (