Study of temperature and salinity effect on encapsulated surfactants ability to alter wettability and decrease interfacial tension
Abstract
In recent decades, the task of increasing the oil recovery factor from productive formations has not lost its relevance. Today, there is a rapidly growing interest in the use of chemical methods to increase oil recovery to enhance production, in particular, using surfactants. To overcome the problem of high adsorption, which prevents the widespread introduction of surfactant flooding in carbonate formations, it is proposed to use the technology of encapsulating surfactants in a solid shell. Thus, the active substance can cover a large part of the reservoir, and therefore more oil can be extracted by injecting surfactants. In this work, the influence of typical reservoir conditions (high temperature and salinity) on the main properties of the dispersions of encapsulated surfactants, namely, a decrease in interfacial tension and a change in wettability, was studied. It is shown that the application of the encapsulation method preserves the necessary properties of surfactants, at which low interfacial tension is observed, and the surface of the carbonate rock becomes more hydrophilic.