Viscous oil recovery using emulsions
AssigneeExxonMobil Upstream Research Company
InventorsRobert D. Kaminsky, Ramesh Varadaraj
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Abstract
The present invention is directed to a method of generating a basic water-in-oil emulsion for use in recovering hydrocarbons from a subterranean formation. The emulsion may be used to displace hydrocarbons from the formation. The emulsions used are ‘basic’ in the sense that they do not have added surfactants and are not solid-stabilized. The emulsions are made using a hydrocarbon having at least one of the following properties: (i) greater than five weight percent (wt %) asphaltene content, (ii) greater than two wt % sulfur content, and (iii) less than 22 dyne/cm interfacial tension between the hydrocarbon liquid and the aqueous liquid.
Claims29
A method for producing viscous hydrocarbons from a subterranean formation, comprising:
- a. selecting a hydrocarbon liquid and an aqueous liquid for generating an emulsion, wherein the hydrocarbon liquid has at least one of the following properties:
- (i) greater than about five weight percent (wt %) asphaltene content, (ii) greater than about two wt % sulfur content, and (iii) less than about 22 dyne/cm interfacial tension between the hydrocarbon liquid and the aqueous liquid;
- b. generating the emulsion having a continuous phase formed from the hydrocarbon liquid and an internal phase formed from the aqueous liquid, wherein the emulsion is a basic emulsion and the emulsion retains at least 70% of the aqueous liquid when the emulsion is used as a drive fluid, wherein a basic emulsion is substantially free from stabilizing solids and substantially free of any added stabilizing agent or component such as those found in artificially stabilized emulsions;
- c. injecting the basic emulsion into the subterranean formation for use as a drive fluid;
- and
- d. producing said viscous hydrocarbons from the formation using the basic emulsion.
A method of generating an emulsion, comprising:
- selecting a hydrocarbon liquid and an aqueous liquid, wherein the hydrocarbon liquid has at least one of the following properties:
- (i) greater than about five weight percent (wt %) asphaltene content, (ii) greater than about two wt % sulfur content, and (iii) less than about 22 dyne/cm interfacial tension between the hydrocarbon liquid and the aqueous liquid;
- forming a basic emulsion from the hydrocarbon liquid and the aqueous liquid, wherein the hydrocarbon liquid is the continuous phase component of the basic emulsion and the aqueous liquid is the internal phase component, wherein a basic emulsion is substantially free from stabilizing solids and substantially free of any added stabilizing agent or component such as those found in artificially stabilized emulsions;
- and
- improving the stability of the basic emulsion wherein the basic emulsion retains at least 70% of the aqueous liquid when the emulsion is used as a drive fluid, comprising:
- stressing the basic emulsion to rupture at least a portion of the internal phase component to produce a stressed emulsion and a broken-out portion of the internal phase component;
- and
- shearing the stressed emulsion with at least a portion of the broken-out portion of the internal phase component.
Dependencies are inferred from the claim text.