Mitigating corrosion of carbon steel tubing and surface scaling deposition in oilfield applications

Patent metadata

Field	Value
Publication number	US-10822926-B2
Application number	US-201815934645-A
Country	US
Kind code	B2
Filing date	Mar 23, 2018
Priority date	Mar 24, 2017
Publication date	Nov 3, 2020
Grant date	Nov 3, 2020

Abstract

Mitigating corrosion and surface scale formation in a sour gas well includes providing an oil-based liquid to a sour gas well having carbon steel tubing with iron sulfide on a surface of the carbon steel tubing, contacting the carbon steel tubing with the oil-based liquid, and adsorbing a first portion of the oil-based liquid onto the iron sulfide, thereby yielding a hydrophobic coating on the carbon steel tubing.

First claim

What is claimed is:

1. A method of mitigating corrosion and surface scale formation in a sour gas well, the method comprising:
separating condensate from a production stream of a sour gas well;
providing the condensate to the sour gas well comprising carbon steel tubing, wherein the carbon steel tubing comprises iron sulfide on a surface of the carbon steel tubing;
contacting the carbon steel tubing with the condensate; and
adsorbing a first portion of the condensate onto the iron sulfide, thereby yielding a hydrophobic coating on the carbon steel tubing.

2. The method of claim 1 , wherein the condensate comprises at least one of diesel fuel, kerosene, or black oil.

3. The method of claim 1 , wherein the iron sulfide is in direct contact with the surface of the carbon steel tubing.

4. The method of claim 1 , comprising:
producing gas from the sour gas well to yield the production stream; and
separating the condensate from the production stream before providing the condensate to the sour gas well.

5. The method of claim 1 , wherein the method does not comprise continuous injection of a corrosion inhibitor into the sour gas well in addition to providing the condensate to the sour gas well.

6. The method of claim 1 , wherein providing the condensate to the sour gas well comprises injecting the condensate between a casing of the sour gas well and the carbon steel tubing.

7. The method of claim 1 , comprising removing a second portion of the condensate from the sour gas well after providing the condensate to the sour gas well.

8. The method of claim 7 , comprising reintroducing the second portion of the oil-based liquid to the sour gas well.

9. The method of claim 1 , comprising producing gas from the sour gas well to yield the production stream comprising water, wherein the hydrophobic coating on the carbon steel tubing prevents direct contact of the water with the carbon steel tubing.

10. The method of claim 1 , wherein the hydrophobic coating inhibits or prevents formation of hydrogen sulfide on the carbon steel tubing.

11. The method of claim 1 , wherein the hydrophobic coating inhibits or prevents corrosion of the carbon steel tubing.

12. A method of mitigating surface scale formation and corrosion in a sour gas well, the method comprising:
producing gas from the sour gas well to yield a production stream, wherein the sour gas well comprises carbon steel tubing comprising iron sulfide on a surface of the carbon steel tubing;
separating condensate from the production stream;
providing the condensate to the sour gas well; and
coating the carbon steel tubing with a first portion of the condensate, wherein coating the carbon steel tubing comprises adsorbing the first portion of the condensate onto the iron sulfide.

13. The method of claim 12 , wherein providing the condensate to the sour gas well comprises injecting the condensate between a casing of the sour gas well and the carbon steel tubing.

14. The method of claim 12 , wherein coating the carbon steel tubing does not comprise coating the carbon steel tubing with chemicals in addition to the condensate.

15. The method of claim 12 , wherein coating the carbon steel tubing with the first portion of the condensate yields a hydrophobic coating on the carbon steel tubing.

16. The method of claim 15 , wherein the hydrophobic coating prevents or inhibits formation of hydrogen sulfide on the carbon steel tubing.

17. The method of claim 15 , wherein the hydrophobic coating prevents or inhibits corrosion of the carbon steel tubing.

18. The method of claim 15 , wherein the hydrophobic coating prevents or inhibits direct contact of water with the carbon steel tubing.

19. The method of claim 12 , comprising removing a second portion of the condensate from the sour gas well.

20. The method of claim 19 , comprising reintroducing the second portion of the condensate to the sour gas well.

Assignees

• Saudi Arabian Oil Co

Inventors

• Wang Qiwei
• Chen Tao

Classifications

• E21B43/40

  Separation associated with re-injection of separated materials {(E21B43/385 takes precedence)} · CPC title

• E21B17/02

  Couplings; joints {(expandable couplings or joints E21B43/106)} · CPC title

• C09K8/54

  Compositions for in situ inhibition of corrosion in boreholes or wells · CPC title

• E21B41/02 Primary

  in situ inhibition of corrosion in boreholes or wells · CPC title

• E21B37/06

  using chemical means for preventing or limiting {, e.g. eliminating,} the deposition of paraffins or like substances · CPC title