Plugging a tubing/casing annulus in a wellbore with a polymer gel
AssigneeMarathon Oil Company
InventorsDavid N. Burdge, Richard W. McAtee, Robert D. Sydansk
Life of this patent
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Abstract
A tubing/casing annulus in a wellbore penetrating a subterranean hydrocarbon-bearing formation is plugged using a gel comprising a high molecular weight, water-soluble carboxylate-containing polymer and a chromic carboxylate complex crosslinking agent. The gel components are combined at the surface and injected into the annulus to form a continuous single-phase gel therein.
Claims12
A process for plugging an annulus formed between a casing and a tube internal and concentric to the casing in a wellbore in fluid communication with a subterranean hydrocarbon-bearing formation, comprising:
- (a) preparing a gelation solution at the surface comprising a water-soluble carboxylate-containing polymer and a complex capable of crosslinking said polymer comprising a chromic species and a carboxylate species;
- (b) injecting said gelation solution into said annulus to be plugged;
- and
- (c) crosslinking said gelation solution to substantial completion in said annulus to form a gel which substantially plugs said annulus.
A process for plugging an annulus formed between a casing and a tube internal and concentric to the casing in a wellbore in fluid communication with a subterranean hydrocarbon-bearing formation, comprising:
- (a) admixing a gelation solution at the surface consisting essentially of a water-soluble carboxylate-containing polymer, a complex capable of crosslinking said polymer and formed of at least one chromic species and at least one acetate species, and a solvent for said polymer and said complex;
- (b) injecting said gelation solution into said annulus to be plugged;
- and
- (c) crosslinking said gelation solution to substantial completion in said annulus to form a nonflowing crosslinked polymer gel which substantially plugs said annulus.
A process for plugging an annulus formed between a casing and a tube internal and concentric to the casing in a wellbore in fluid communication with a subterranean hydrocarbon-bearing formation, comprising:
- (a) admixing a gelation solution at the surface consisting essentially of a water-soluble carboxylate-containing polymer, a complex capable of crosslinking said polymer and formed of at least one chromic species, at least one acetate species, and at least one species selected from the group consisting of electronegative oxygen species, electronegative hydroxide species, inorganic monovalent ions, inorganic divalent ions, water molecules, and mixtures thereof, and a solvent for said polymer and said complex;
- (b) injecting said gelation solution into said annulus to be plugged;
- and
- (c) crosslinking said gelation solution to substantial completion in said annulus to form a nonflowing crosslinked polymer gel which substantially plugs said annulus.
Dependencies are inferred from the claim text.