Patent ID: 8061422

Claim:
A method for recovering liquid hydrocarbons from an underground reservoir, comprising (a) closing production wells, to form a sealed reservoir; (b) injecting a first surfactant solution into the reservoir, wherein the first surfactant increases the pressure in the reservoir; (c) maintaining the sealed reservoir, to maintain increased pressure; (d) opening production wells, wherein production wells remove the released liquid hydrocarbons; (e) injecting a second surfactant solution into the reservoir, wherein injecting a second surfactant solution comprises maintaining the increased pressure within the reservoir; (f) removing liquid hydrocarbons, the first surfactant solution, and the second surfactant solution from the reservoir; (g) recycling the first surfactant solution to step (b) and the second surfactant solution to step (e); and (h) recovering the liquid hydrocarbons.