Use of a solvent and emulsion for in situ oil recovery

摘要

Described is a way to reduce solvent usage in solvent-dominated oil recovery processes through the use of an emulsion. Injection of an emulsion into an oil reservoir is performed as an alternative or supplement to solvent injection to minimize solvent usage per unit amount of oil recovered. The emulsion may contain solvent and the solvent may form an external-phase of the emulsion. A solvent-external emulsion may be injected and formed using an aqueous liquid or a gas as the internal phase. The emulsion may be an aqueous-external, vapor-internal emulsion with solvent being injected separately or simultaneously. Polymer may be added to viscosify the emulsions and use them for flow diversion in a solvent-dominated process.