Single-fluid mixed scale dissolution
AssigneeHalliburton Energy Services, Inc.
InventorsEnrique Antonio Reyes, Sarai Santos, Kristina Henkel Holan, Antonio Recio, III
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Abstract
Methods and treatment fluids for removing mixed scale. A treatment fluid is introduced into a wellbore comprising a mixed scale of interspersed calcium carbonate and calcium sulfate. The treatment fluid comprises: phosphonomethyliminodiacetic acid, glycine-N,N-bis(methylene phosphonic acid), or a combination thereof; and an aqueous base fluid. The treatment fluid has a pH in a range between about 6 to about 8. The method further comprises contacting the mixed scale with the treatment fluid.
Claims20
A method of removing mixed scale, the method comprising:
- introducing a treatment fluid into a wellbore comprising a mixed scale of interspersed calcium carbonate and calcium sulfate, wherein the treatment fluid comprises:
- phosphonomethyliminodiacetic acid, glycine-N,N-bis(methylene phosphonic acid), or a combination thereof, and
- an aqueous base fluid;
- wherein the treatment fluid has a pH in a range between about 6 to about 8;
- and
- contacting the mixed scale with the treatment fluid.
A treatment fluid for treating mixed scale, the treatment fluid comprising:
- phosphonomethyliminodiacetic acid, glycine-N,N-bis(methylene phosphonic acid), or a combination thereof, and
- an aqueous base fluid;
- wherein the treatment fluid has a pH in a range between about 6 to about 8;
- wherein the treatment fluid does not comprise a carboxylate-containing alkanol, a carboxylated alkyl halide, or a multicarboxylic acid;
- and wherein the treatment fluid does not comprise carbonate or bicarbonate.
A system for removing mixed scale from a wellbore, the system comprising:
- a treatment fluid comprising:
- phosphonomethyliminodiacetic acid, glycine-N,N-bis(methylene phosphonic acid), or a combination thereof, and
- an aqueous base fluid;
- wherein the treatment fluid has a pH in a range between about 6 to about 8;
- wherein the treatment fluid does not comprise a carboxylate-containing alkanol, a carboxylated alkyl halide, or a multicarboxylic acid;
- and wherein the treatment fluid does not comprise carbonate or bicarbonate;
- mixing equipment configured to mix the phosphonomethyliminodiacetic acid or the glycine-N,N-bis(methylene phosphonic acid) and the aqueous base fluid to provide the treatment fluid;
- and
- pumping equipment configured to pump the treatment fluid into the wellbore to a location comprising the mixed scale.
Dependencies are inferred from the claim text.