Process for removing metal naphthenate from crude hydrocarbon mixtures

Patent metadata

Field	Value
Publication number	US-10358609-B2
Application number	US-201415538861-A
Country	US
Kind code	B2
Filing date	Dec 23, 2014
Priority date	Dec 23, 2014
Publication date	Jul 23, 2019
Grant date	Jul 23, 2019

Abstract

Metal naphthenate is removed from a crude hydrocarbon mixture by a process. The process includes mixing the crude hydrocarbon mixture comprising metal naphthenate with an acid in the presence of water, wherein the acid converts the metal naphthenate to naphthenic acid and metal salt; allowing the metal salt to partition into a water phase; and separating the crude heavy hydrocarbon mixture comprising naphthenic acid and the water phase comprising the metal salt.

First claim

The invention claimed is:

1. A process for removing metal naphthenate from a crude hydrocarbon mixture, comprising:
mixing said crude hydrocarbon mixture comprising metal naphthenate with an acid in the presence of water, wherein said acid converts said metal naphthenate to naphthenic acid and metal salt;
allowing said metal salt to partition into a water phase; and
separating said crude hydrocarbon mixture comprising naphthenic acid and said water phase comprising said metal salt.

2. The process as claimed in claim 1 , wherein said crude hydrocarbon mixture initially comprises at least 40 ppm wt of said metal naphthenate.

3. The process as claimed in claim 1 , further comprising adding diluent to said crude hydrocarbon mixture, prior to mixing said crude hydrocarbon mixture with said acid.

4. The process as claimed in claim 1 , wherein said acid has a pKa of less than 7.

5. The process as claimed in claim 1 , wherein said acid is an inorganic acid.

6. The process as claimed in claim 1 , wherein said acid is an organic acid.

7. The process as claimed in claim 1 , wherein said mixing is achieved by injecting said acid into a line conveying said crude hydrocarbon mixture.

8. The process as claimed in claim 1 , wherein said mixing creates water droplets comprising said acid.

9. The process as claimed in claim 1 , wherein said acid is added to a crude hydrocarbon mixture extracted from a subterranean formation.

10. The process as claimed in claim 1 , wherein said crude hydrocarbon mixture comprises at least 95% by volume of hydrocarbon.

11. The process as claimed in claim 1 , which is carried out at a wellsite.

12. The process as claimed in claim 1 , wherein said crude hydrocarbon mixture obtained after separation comprises less than 100 ppm wt metal ion as metal naphthenate and/or 0.1 to 12 wt % naphthenic acid.

13. The process as claimed in claim 1 , further comprising treating said crude hydrocarbon mixture comprising naphthenic acid to reduce its API.

14. The process as claimed in claim 1 , further comprising pumping said crude hydrocarbon mixture comprising naphthenic acid to a refinery.

15. A process for producing hydrocarbon from a hydrocarbon containing formation comprising:
extracting a crude hydrocarbon mixture from a hydrocarbon containing formation;
mixing said crude hydrocarbon mixture comprising metal naphthenate with an acid in the presence of water, wherein said acid converts said metal naphthenate to naphthenic acid and metal salt;
allowing said metal salt to partition into a water phase;
separating said crude hydrocarbon mixture comprising naphthenic acid and said water phase comprising said metal salt; and
pumping said crude hydrocarbon mixture comprising naphthenic acid to a refinery.

16. The process as claimed in claim 15 , further comprising adding a diluent to said crude hydrocarbon mixture extracted from said formation prior to mixing with said acid.

17. The process as claimed in claim 15 , further comprising upgrading said crude hydrocarbon mixture comprising naphthenic acid prior to pumping to a refinery.

18. A system for removing metal naphthenate from a crude hydrocarbon mixture comprising:
a container comprising an acid;
a line for conveying a crude hydrocarbon mixture to a first separator;
a means for adding an acid to said line conveying a crude hydrocarbon mixture to said first separator, wherein said means is fluidly connected to said container comprising acid; and
said first separator for separating the crude hydrocarbon mixture comprising naphthenic acid and a water phase comprising a metal salt, wherein said first separator has an inlet for crude hydrocarbon mixture, an outlet for crude hydrocarbon mixture comprising naphthenic acid and an outlet for the water phase comprising the metal salt.

19. The system as claimed in claim 18 , wherein said outlet for crude hydrocarbon mixture comprising naphthenic acid of said first separator is fluidly connected to a treater.

20. The system as claimed in claim 18 , wherein said first separator is a bulk separator.

21. The system as claimed in claim 18 , wherein said outlet for crude hydrocarbon mixture comprising naphthenic acid of said first separator is fluidly connected to a second separator.

22. The system as claimed in claim 21 , wherein said second separator is a gravity separator.

Assignees

• Statoil Petroleum As

Inventors

• Grande Knut
• Kummernes Hege
• Høvik Kim Reidar
• Vindstad Jens Emil
• Mediaas Heidi
• Rosvoll Jorunn Steinsland
• Haug Ingvild Johanne

Classifications

• C10G2300/308

  Gravity, density, e.g. API · CPC title

• C10G2300/205

  Metal content · CPC title

• C10G53/10 Primary

  including at least one acid-treatment step · CPC title

• C10G31/08

  by treating with water · CPC title

• C10G17/04 Primary

  Liquid-liquid treatment forming two immiscible phases · CPC title