Experimental Investigation of Surfactant Partition in Heavy Oil/Water/Sand Systems

Abstract

Surfactant adsorption on reservoir rocks or sands is one of the major factors that may significantly reduce the effectiveness of an alkaline/surfactant flood for oil recovery. It is difficult to determine the surfactant adsorption by measuring the difference between surfactant concentrations before and after adsorption when the water phase contains fine oil drops. In this study, an extraction method was used to quantitatively determine the adsorptions of surfactant on sand and at oil-water interfaces in an alkaline/surfactant flood for heavy oil recovery. Experimental results showed that the formation of emulsions dramatically reduced surfactant loss to sand surface. The adsorptions of surfactant on sand and at oil-water interface were determined under various alkaline concentrations and salinities. The results provide useful information for evaluating and predicting surfactant adsorption in alkaline/surfactant flooding for enhanced heavy oil recovery.