Monovalent brines for use as wellbore fluids

Patent metadata

Field	Value
Publication number	US-11920082-B2
Application number	US-202017776408-A
Country	US
Kind code	B2
Filing date	Nov 9, 2020
Priority date	Nov 13, 2019
Publication date	Mar 5, 2024
Grant date	Mar 5, 2024

Abstract

The invention relates to a wellbore fluid, which is a monovalent brine comprising one or more alkali bromide salt(s) and one or more TCT-reducing additive(s) selected from the group consisting of alkali nitrates. A method of treating a subterranean formation, comprising placing the wellbore fluids of the invention in a wellbore in the subterranean formation is also provided.

First claim

The invention claimed is:

1. A wellbore fluid, which is a monovalent brine comprising one or more alkali bromide salt(s) and one or more TCT-reducing additive (s) selected from the group consisting of alkali nitrates, wherein the monovalent brine comprises water and a binary salt mixture consisting of sodium bromide and alkali nitrate, said monovalent brine being of density in the range from 1.47 to 1.55 g/ml; and
wherein the monovalent brine is sodium bromide/sodium nitrate brine of density from 1.49 gr/ml to 1.52 gr/ml and TCT below −5.0° C. or
wherein the monovalent brine is sodium bromide/potassium nitrate brine of density from 1.48 gr/ml to 1.51 gr/ml and TCT below −5.0° C.

2. A wellbore fluid according to claim 1 , comprising from 35 to 38% by weight of the sodium bromide and from 13 to 18% by weight of the sodium nitrate in aqueous solution.

3. A wellbore fluid according to claim 1 , comprising from 35 to 42% by weight of sodium bromide and from 7 to 10% by weight of the potassium nitrate in aqueous solution.

4. A wellbore fluid according to claim 1 , having a pH from 6 to 8.

5. A wellbore fluid according to claim 1 , having a pH from 7 to 8.

6. A wellbore fluid according to claim 1 , having pH 7.5.

7. A wellbore fluid, which is a monovalent brine comprising one or more alkali bromide salt(s) and one or more TCT-reducing additive (s) selected from the group consisting of alkali nitrates, said monovalent brine comprising water and a ternary salt mixture consisting of a first alkali bromide, a second alkali bromide and alkali nitrate, wherein the first alkali bromide is sodium bromide, the second alkali bromide is lithium bromide, potassium bromide or cesium bromide and the alkali nitrate is sodium nitrate; and
wherein the monovalent brine is sodium bromide/lithium bromide/sodium nitrate brine of density from 1.47 gr/ml to 1.49 gr/ml and TCT below −5.0° C., or
wherein the monovalent brine is sodium bromide/potassium bromide/sodium nitrate brine of density from 1.51 gr/ml to 1.54 gr/ml and TCT below −5.0° C., or
wherein the monovalent brine is sodium bromide/cesium bromide/sodium nitrate brine of density from 1.53 gr/ml to 1.57 gr/ml and TCT below −5.0° C.

8. A wellbore fluid according to claim 7 , comprising from 30 to 35% by weight of the sodium bromide; from 5 to 10% by weight of the lithium bromide; and from 6 to 10% by weight of the sodium nitrate in aqueous solution.

9. A wellbore fluid according to claim 7 , comprising from 30 to 37% by weight of the sodium bromide; from 5 to 10% by weight of the potassium bromide; and from 6 to 10% by weight of the sodium nitrate in aqueous solution.

10. A wellbore fluid according to claim 7 , comprising from 33 to 37% by weight of the sodium bromide; from 5 to 10% by weight of the cesium bromide; and from 5 to 10% by weight of the sodium nitrate in aqueous solution.

11. A method of treating a subterranean formation, comprising placing the wellbore fluids of claim 1 in a wellbore in the subterranean formation.

Assignees

• Bromine Compounds Ltd

Inventors

• Shandalov Elizabeta
• Masarwa Mohamad
• Cohen David

Classifications

• C09K8/528 Primary

  inorganic depositions, e.g. sulfates or carbonates · CPC title

• C09K8/845

  containing inorganic compounds · CPC title

• C09K8/05 Primary

  containing inorganic compounds only, e.g. mixtures of clay and salt · CPC title