The search for methods and technologies for enhanced oil recovery is a priority task for Vietsovpetro JV. The Lower Miocene of the Northern Area of White Tiger field has a long history of development and injection process with the highest water cut and relatively low oil viscosity. The specific characteristics of the area geology, petrophysical properties, reservoir properties, energy and temperature regimes, formation fluid properties and development indicators determined its selection as a pilot test object. For the selected pilot area, successive laboratory studies were carried out to determine the parameters of the fluid and rock, the surfactant and polymer, the formulation of the surfactant-polymer composition and filtration in the pore medium using core material. The choice of surfactants for the current conditions of the field was carried out on the basis of a hydrophilic / hydrophobic ratio for an equivalent separation between oil and synthetic solution. For this study, thermostable hydrophilic molecules from two types of surfactants are considered. Three filtration tests were carried out to assess dynamic adsorption and mechanical destruction on the prepared core material. As a result of the experiments, the oil displacement efficiency was 0.75-0.86, which is higher by 30-40% than displacement efficiency obtained during flooding (0.45). The following parameters were determined: the optimal concentrations of surfactant and polymer, the formulation of a thermally stable surfactant-polymer composition that allows achieving ultra-low phase tension and is suitable for operation in the conditions of the Lower Miocene object of the Northern Area of the White Tiger field.
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