Enhanced oil recovery mechanism with nanofluid injection

Abstract

The development and application of enhanced oil recovery technologies using nanofluids have been observed in last decade. It was found that the use of these reagents leads to the wettability alteration of the pore walls of the rock, an interfacial tension reduction, a decrease in oil viscosity, and an increase in the disjoining pressure. This paper presents the results of studying the displacement of residual oil on homogeneous quartz sandstone using the nanofluids, obtained by peptizing the sediments in a mixture of seawater with calcium and magnesium salts. Nitric and organic acids were used as peptizing agents. When using the developed nanofluids, an increase in oil production by 15-20% was achieved in comparison with seawater. A new approach for the mechanism of action of nanoparticles on the formation, leading to an increase in oil production, is proposed. Keywords: oil recovery; displacement efficiency; nanofluid; peptization; wettability alteration; interfacial tension.