Compositions and methods for inhibiting shale and preventing shale accretion

Patent metadata

Field	Value
Publication number	US-12060518-B2
Application number	US-202217649077-A
Country	US
Kind code	B2
Filing date	Jan 27, 2022
Priority date	Jul 1, 2021
Publication date	Aug 13, 2024
Grant date	Aug 13, 2024

Abstract

Methods of treating a subterranean formation including shale include preparing a treatment fluid by mixing an aqueous base fluid and a dry polyvinyl pyrrolidone (PVP) in flake or powder form having a molecular weight between about 500,000 and about 2,000,000 and introducing the treatment fluid in the subterranean formation.

First claim

What is claimed is:

1. A method of treating a subterranean formation comprising shale, the method comprising:
providing dry polyvinyl pyrrolidone (PVP) at a wellsite, wherein the dry PVP has a molecular weight between about 900,000 to about 2,000,000 and less than 2% moisture;
preparing a treatment fluid by mixing, at the wellsite, an aqueous base fluid and the dry PVP; and
introducing the treatment fluid in the subterranean formation,
wherein the PVP is in flake form and has a reduced solubility time in comparison to a powder form, and
wherein the treatment fluid provides superior encapsulation and enhanced shale inhibition performance relative to a treatment fluid not having the dry PVP having the molecular weight between about 900,000 to about 2,000,000 and less than 2% moisture.

2. The method of claim 1 , wherein the PVP is present in the treatment fluid in an amount sufficient to inhibit degradation of the shale or prevent accretion of the shale.

3. The method of claim 2 , wherein the PVP is present in the treatment fluid in an amount in a range of about 0.04 pounds per barrel (ppb) to about 10 ppb of the treatment fluid.

4. The method of claim 3 , wherein the PVP is present in the treatment fluid in an amount in a range of about 1 ppb to about 8 ppb.

5. The method of claim 1 , wherein the treatment fluid further comprises a salt.

6. The method of claim 5 , wherein the salt comprises potassium chloride, calcium chloride, sodium chloride, potassium formate, calcium bromide, potassium carbonate, or a mixture thereof.

7. The method of claim 1 , wherein the aqueous base fluid comprises fresh water.

8. The method of claim 1 , wherein the treatment fluid comprises a drilling fluid.

9. The method of claim 1 , wherein the PVP has a molecular weight between about 900,000 to about 1,500,000.

10. The method of claim 1 , wherein the treatment fluid provides an increased shale retention and/or a decreased accretion relative to a treatment fluid comprising an aqueous PVP shale inhibitor.

11. The method of claim 1 , wherein the PVP flakes have a reduced moisture and/or a reduced specific gravity relative to the PVP powder.

12. The method of claim 1 , wherein the dry PVP has less than 1% moisture.

13. A method of drilling a well in a subterranean formation comprising shale, the method comprising:
preparing a drilling fluid, at a wellsite, by mixing an aqueous base fluid and a dry polyvinyl pyrrolidone (PVP) in flake form having a molecular weight between about 900,000 to about 2,000,000, and less than 2% moisture;
introducing the drilling fluid into a well bore in contact with a drill bit and the subterranean formation; and
using the drilling fluid to drill in at least a portion of the subterranean formation,
wherein the PVP is in flake form and has a reduced solubility time in comparison to a powder form, and
wherein the drilling fluid provides superior encapsulation and enhanced shale inhibition performance relative to a drilling fluid not having the dry PVP having the molecular weight between about 900,000 to about 2,000,000 and less than 2% moisture.

14. The method of claim 13 , wherein the PVP is present in the drilling fluid in an amount in a range of about 0.04 pounds per barrel (ppb) to about 10 ppb of the drilling fluid.

15. The method of claim 13 , wherein the drilling fluid further comprises a salt.

16. The method of claim 15 , wherein the salt comprises potassium chloride, calcium chloride, sodium chloride, potassium formate, calcium bromide, potassium carbonate, or a mixture thereof.

17. The method of claim 13 , wherein the PVP has a molecular weight between about 900,000 to about 1,500,000.

18. The method of claim 13 , wherein the dry PVP has less than 1% moisture.

Assignees

• Halliburton Energy Services Inc

Inventors

• Chavan Sandeep
• Miller Jeffrey J

Classifications

• E21B21/062

  by mixing components · CPC title

• C09K2208/12

  Swell inhibition, i.e. using additives to drilling or well treatment fluids for inhibiting clay or shale swelling or disintegrating · CPC title

• C09K8/12 Primary

  containing synthetic organic macromolecular compounds or their precursors · CPC title

• C09K8/035 Primary

  Organic additives · CPC title