Patent ID: 8684079

Claim:
A method of recovering hydrocarbons from an underground reservoir of the hydrocarbons, the method comprising: (a) injecting fluid, into the underground reservoir, comprising an emulsion and a viscosity-reducing solvent, (b) allowing the viscosity-reducing solvent to contact and at least partially dissolve into the hydrocarbons in the underground reservoir and reduce a viscosity of the hydrocarbons; and (c) producing reduced viscosity hydrocarbons from the underground reservoir; wherein the viscosity-reducing solvent has a viscosity at a reservoir pressure and temperature less than 1% of the viscosity of the hydrocarbons at the same pressure and temperature, the emulsion having an internal phase and an external phase, and the internal phase being substantially chemically inert with respect to components in the underground reservoir, and wherein the hydrocarbon recovery is by a cyclic solvent-dominated recovery process comprising injecting the emulsion and the viscosity-reducing solvent into a well completed in the underground reservoir, and then halting injection, and then producing at least a fraction of the emulsion, the viscosity-reducing solvent, and the hydrocarbons from the underground reservoir, and then halting production, and then repeating such cycles of injection and production.