Foam for secondary and tertiary recovery

摘要: Oil is moved in a subterranean oil-bearing formation by displacing the oil with foamed oil-external micellar dispersion. The dispersion, before foaming, contains 2 90 percent volume hydrocarbon, at least about 4 surfactant, 5 - aqueous medium, and optionally 0.01 20 cosurfactant and/or 0.0001 weight electrolyte. Useful gases for foaming dispersion include air, natural gas, nitrogen, flue gases, etc. can be it injected into or situ of formation. A mobility buffer fluid drive may used to displace foam toward production well recover crude therethrough.