Patent ID: 7624804

Claim:
A method for recovering oil from a gas-lifted oil well penetrating a subterranean oil-bearing formation, the method comprising: A) providing a lift gas and a surfactant at an oil well wherein the oil well penetrates a subterranean oil-bearing formation and has formation fluids in the well bore; B) injecting a lift gas into the oil well; and C) injecting a surfactant into the oil well, wherein i) the surfactant functions to: (a) reduce the surface tension between the formation fluids and the lift gas; (b) create a lift gas-formation fluid foam; or (c) both (a) and (b); ii) the surfactant and lift gas are injected into the oil well at a depth sufficiently deep to lift formation fluids to the surface; and iii) the surfactant consists essentially of a member selected from the group consisting of sultaines and all salts thereof, hydroxy sultaines and all salts thereof, and mixtures thereof.