PROCESS FOR RECOVERING OIL

摘要

Process for recovering oil which process comprises (a) injecting surfactant into an oil-bearing formation and recovering from the formation a mixture containing oil, water and surfactant, (b) treating the mixture recovered in step (a) with salt or an aqueous salt solution and separating the treated mixture into an oil phase containing surfactant and an aqueous phase, and (c) washing the oil phase containing surfactant obtained in step (b) with water and recovering oil having a reduced surfactant content.