The present invention addresses to an oil-in-water microemulsion composition to increase the injectivity of produced water in reservoirs of oil production fields, contemplates a solution that has the potential to reduce the water-oil interfacial tension, to increase the mobility of produced water in the reservoir and to restore the wettability of the reservoir rock.

The present invention addresses to an oil-in-water microemulsion composition to increase the injectivity of produced water in reservoirs of oil production fields, contemplates a solution that has the potential to reduce the water-oil interfacial tension, to increase the mobility of produced water in the reservoir and to restore the wettability of the reservoir rock.

The invention relates to a method including a system of additives which increase fluidity and/or flow capacity and minimize pressure drops from the steps of lifting in production wells, collection lines, dehydration systems and ducts for transporting heavy and extra-heavy hydrocarbons. In addition, the injected system of chemical additives increases the dilution capacity of the solvents that need to be applied to improve the quality of the crude oil (reduce viscosity and density, and increase API gravity), thereby facilitating the dehydration and transport.

This invention relates to a surfactant composition, production and use thereof in tertiary oil recovery. The present surfactant composition comprises a cationic surfactant and an anionic-nonionic surfactant, and exhibits significantly improved interfacial activity and stability as compared with the prior art. With the present surfactant composition, a flooding fluid composition for tertiary oil recovery with improved oil displacement efficiency and oil washing capability as compared with the prior art could be produced.

This invention relates to a surfactant composition, production and use thereof in tertiary oil recovery. The present surfactant composition comprises a cationic surfactant and an anionic-nonionic surfactant, and exhibits significantly improved interfacial activity and stability as compared with the prior art. With the present surfactant composition, a flooding fluid composition for tertiary oil recovery with improved oil displacement efficiency and oil washing capability as compared with the prior art could be produced.

The invention relates to a method for recovery of hydrocarbons present in an underground formation by injection of a saline aqueous solution comprising at least one surfactant, by means of a numerical flow simulator including a model of the evolution of the interfacial tension between the saline aqueous solution and the hydrocarbons as a function at least of salinity, wherein the interfacial tension evolution model is calibrated as follows: i) carrying out interfacial tension measurements for a plurality of emulsions having distinct salinity values corresponding at least to the optimum salinity, to two salinities bounding the optimum salinity in a 5-10% limit, to the zero salinity and to the solubility limit of the salts; ii) determining the constants of the interfacial tension evolution model by minimizing a difference between the model and the interfacial tension measurements.

The invention relates to a method for recovery of hydrocarbons present in an underground formation by injection of a saline aqueous solution comprising at least one surfactant, by means of a numerical flow simulator including a model of the evolution of the interfacial tension between the saline aqueous solution and the hydrocarbons as a function at least of salinity, wherein the interfacial tension evolution model is calibrated as follows: i) carrying out interfacial tension measurements for a plurality of emulsions having distinct salinity values corresponding at least to the optimum salinity, to two salinities bounding the optimum salinity in a 5-10% limit, to the zero salinity and to the solubility limit of the salts; ii) determining the constants of the interfacial tension evolution model by minimizing a difference between the model and the interfacial tension measurements.

Recovering heavy oil from a subterraneous formation penetrated by at least one injection well and one production well, by injecting into the injection well a mixture of steam and an alkyl alkoxylated carboxylate salt, increasing the apparent viscosity of the steam while at the same time lowering the steam mobility, and recovering oil from the subterranean formation.

Recovering heavy oil from a subterraneous formation penetrated by at least one injection well and one production well, by injecting into the injection well a mixture of steam and an alkyl alkoxylated carboxylate salt, increasing the apparent viscosity of the steam while at the same time lowering the steam mobility, and recovering oil from the subterranean formation.

Disclosed are surface-modified nanoparticles and surfactants used in compositions and methods for enhancing hydro-carbon recovery from subterranean formations.