Characteristics of Oil Displacements by Aqueous Surfactant Solutions

Abstract

ABSTRACT The aim of this laboratory work was a detailed study of oil recovery ability of aqueous surfactant solutions. The first part included determination of relevant physical chemical properties of additive solutions, i. e. interfacial and rheological properties, phase diagram exploration as well as an evaluation of the specific adsorption-retention properties of surfactant polymer solutions in porous media used for oil recovery tests. In the second part, the results of the series of oil displacements were analysed –to give a precise description of the main features of displacements by aqueous surfactant solutions,–to assess their oil recovery efficiency, shown to depend on surfactant concentration in slug injected, consecutive or simultaneous injection mode of polymer and surfactant and additive retention properties in the porous media chosen,–to compare the oil recovery performances of surfactant solutions and microemulsions taken from the same Winsor III type diagram. Finally, application of a Buckley-Leverett type approach was considered to aid in the interpretation of the successive displacement steps observed during flooding by surfactant solutions at low or moderate concentrations.