Methods of using invertible oil external-water internal fluids in subterranean applications
AssigneeHalliburton Energy Services, Inc.
InventorsRobert S. Taylor, David W. Ritter
Life of this patent
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Abstract
Methods of using invertible oil external-water internal emulsions in drilling, hydraulic fracturing, gravel packing and completion and then inverting the emulsion to a water external-oil internal emulsion are provided. The methods basically comprise the steps of contacting the oil external-water internal emulsion with an aqueous acid solution containing an anionic sulfonate surfactant for preventing aqueous acid solution-crude oil emulsions and crude oil sludging and a chemical for preventing the anionic sulfonate surfactant from reacting with the emulsifier in the oil external-water internal emulsion.
Claims41
A method of treating a subterranean formation comprising the steps of:
- providing a treatment fluid comprising an invertible oil external-water internal emulsion stabilized with a nonionic emulsifier;
- pumping the treatment fluid into a subterranean formation;
- providing an aqueous acid solution comprising an acid, an anionic sulfonate surfactant, and a chemical for preventing the anionic sulfonate surfactant from reacting with the nonionic emulsifier after the nonionic emulsifier is made cationic by the acid;
- contacting the invertible oil external-water internal emulsion with the aqueous acid solution to substantially invert the emulsion;
- and,
- substantially removing the inverted water external-oil internal emulsion from the subterranean formation.
A method of fracturing a subterranean formation comprising the step of:
- inserting an invertible oil external-water internal emulsion fracturing fluid stabilized with a nonionic emulsifier into the subterranean formation at a pressure sufficient to create at least one fracture therein;
- and
- providing an aqueous acid solution comprising an acid, an anionic sulfonate surfactant, and a chemical for preventing the anionic sulfonate surfactant from reacting with the nonionic emulsifier after the nonionic emulsifier is made cationic by the acid;
- contacting the invertible oil external-water internal emulsion with the aqueous acid solution to substantially invert the emulsion;
- and,
- substantially removing the inverted water external-oil internal emulsion from the subterranean formation.
A method of installing a gravel pack comprising the steps of:
- providing a gravel pack composition comprising gravel particles and an invertible oil external-water internal emulsion delivery fluid stabilized with a nonionic emulsifier;
- introducing the gravel pack composition to the well bore so that the gravel particles form a gravel pack substantially adjacent to the wellbore;
- providing an aqueous acid solution comprising an acid, an anionic sulfonate surfactant, and a chemical for preventing the anionic sulfonate surfactant from reacting with the nonionic emulsifier after the nonionic emulsifier is made cationic by the acid;
- contacting the invertible oil external-water internal emulsion with the aqueous acid solution to substantially invert the emulsion;
- and,
- substantially removing the inverted water external-oil internal emulsion from the subterranean formation.
A completion method comprising the steps of:
- providing a completion fluid comprising an invertible oil external-water internal emulsion delivery fluid stabilized with a nonionic emulsifier;
- introducing the completion fluid to a well bore so as to substantially fill at least a section of the well bore;
- providing an aqueous acid solution comprising an acid, an anionic sulfonate surfactant, and a chemical for preventing the anionic sulfonate surfactant from reacting with the nonionic emulsifier after the nonionic emulsifier is made cationic by the acid;
- contacting the invertible oil external-water internal emulsion with the aqueous acid solution to substantially invert the emulsion;
- and,
- substantially removing the inverted water external-oil internal emulsion from the well bore.
Dependencies are inferred from the claim text.