Subsea sour gas and/or acid gas injection systems and methods

Patent metadata

Field	Value
Publication number	US-9404345-B2
Application number	US-201214123952-A
Country	US
Kind code	B2
Filing date	May 24, 2012
Priority date	Jul 1, 2011
Publication date	Aug 2, 2016
Grant date	Aug 2, 2016

Abstract

A hydrocarbon processing method, including processing a gaseous hydrocarbon stream to form a first production stream and a first injection stream; and compressing the first injection stream in a compressor placed at a selected location below a surface of a sea; wherein the location of the subsea compressor relative to a nearest inhabited area is determined based on a bubble plume trajectory of a model leak of the first injection stream from the compressor; and wherein the bubble plume trajectory is determined using one or more crossflow momentum parameters is disclosed herein. Also disclosed are hydrocarbon processing facilities having subsea compressors placed at such selected locations, processes for designing such hydrocarbon processing facilities, and a mathematical model useful in such methods, processes, and facilities.

First claim

We claim:

1. A hydrocarbon processing method comprising:
processing a gaseous hydrocarbon stream to form a first production stream and a first injection stream; and
compressing the first injection stream in a compressor placed at a selected location below a surface of a sea;
wherein the location of the subsea compressor relative to a nearest inhabited area is determined based on a bubble plume trajectory of a model leak of the first injection stream from the compressor; and
wherein the bubble plume trajectory is determined using one or more crossflow momentum parameters.

2. The method of claim 1 , wherein the crossflow momentum parameter includes terms for current and/or buoyancy effects.

3. The method of claim 1 , further comprising describing the bubble plume trajectory by one or more of plume rise time, waterline gas velocity, and waterline plume radius.

4. The method of claim 1 , wherein the bubble plume trajectory is further determined by one or more of the pressure of the conduit having the leak, the depth of the sea, the horizontal distance of the subsea compressor from the inhabited area, the salinity of the sea, the temperature of the water, the density of the components of the first injection stream, the velocity of the water currents, and the leak diameter.

5. The method of claim 1 , wherein the first injection stream is one of an acid gas stream or a sour gas stream.

6. The method of claim 1 , wherein the compressor is located at a depth of about 300 meters or greater.

7. The method of claim 1 , wherein a leak of the first injection stream from the compressor has a waterline gas velocity of less than about 6 meters/second.

8. The method of claim 1 , wherein a leak of the first injection stream from the compressor has a waterline gas velocity of less than about 3 meters/second.

9. The method of claim 1 , wherein a leak of the first injection stream from the compressor has a plume rise time of greater than about 2.0 minutes.

10. The method of claim 1 , wherein a leak of the first injection stream from the compressor has a plume rise time of greater than about 10.0 minutes.

11. The method of claim 1 , wherein the producing and/or processing steps occur at an offshore platform.

12. The method of claim 10 , wherein the subsea compressor is located at one of the sea floor and a support structure fixedly attached to the offshore platform.

13. The method of claim 1 , wherein the subsea compressor is located at a horizontal distance of about 300 meters or more from the inhabited area.

14. A hydrocarbon processing facility comprising:
a gas processing system configured to receive and process a gaseous hydrocarbon stream to produce at least one injection gas stream and at least one production gas stream;
an acid gas injection system comprising a compressor, configured to compress and inject the at least one injection gas stream, the compressor being placed at a selected location below the surface of a sea,
wherein the location of the subsea compressor relative to a nearest inhabited area is determined based on a bubble plume trajectory of a model leak of the at least one injection stream from the compressor; and
wherein the bubble plume trajectory is determined using one or more crossflow momentum parameters.

15. The facility of claim 14 , wherein the crossflow momentum parameter includes terms for current and/or buoyancy effects.

16. The facility of claim 14 , wherein the bubble plume trajectory is described by one or more of plume rise time, waterline gas velocity, and waterline plume radius.

17. The facility of claim 14 , wherein the bubble plume trajectory is further determined by one or more of the pressure of the conduit having the leak, the depth of the sea, the horizontal distance of the subsea compressor from the inhabited area, the salinity of the sea, the temperature of the water, the density of the components of the at least one injection stream, the velocity of the water currents, and the leak diameter.

18. The facility of claim 14 , wherein the at least one injection stream is one of an acid gas stream or a sour gas stream.

19. The facility of claim 14 , wherein the compressor is located at a depth of about 300 meters or greater.

20. The facility of claim 14 , wherein a leak of the at least one injection stream from the compressor has a waterline gas velocity of less than about 6 meters/second.

21. The facility of claim 14 , wherein a leak of the at least one injection stream from the compressor has a waterline gas velocity of less than about 3 meters/second.

22. The facility of claim 14 , wherein a leak of the at least one injection stream from the compressor has a plume rise time of greater than about 2.0 minutes.

23. The facility of claim 14 , wherein a leak of the at least one injection stream from the compressor has a plume rise time of greater than about 10.0 minutes.

24. The facility of claim 14 , wherein the facility comprises an offshore platform.

25. The facility of claim 24 , wherein the compressor is located at a location selected from the group consisting of the sea floor and a support structure fixedly attached to the offshore platform.

26. The facility of claim 14 , wherein the compressor is located at a horizontal distance of about 300 meters or more from the inhabited area.

27. A process for designing an integrated hydrocarbon gas processing facility, the process comprising:
providing an offshore production platform having an inhabited area;
providing at least one gas sweetening unit located on the offshore production platform;
wherein the at least one gas sweetening unit is in fluid communication with at least one liquid separation unit and at least one subsea compressor unit; and
determining a selected location of the subsea compressor relative to a nearest inhabited area;
wherein the determination is based on a bubble plume trajectory of a model leak from the compressor; and

optimizing the time a leak of gas from the subsea compressor takes to reach the inhabited area.

28. The process of claim 27 , wherein the bubble plume trajectory is determined using one or more crossflow momentum parameters.

29. The process of claim 28 , wherein the crossflow momentum parameter includes terms for current and/or buoyancy effects.

30. The process of claim 27 , wherein the bubble plume trajectory is described by one or more of plume rise time, waterline gas velocity, and waterline plume radius.

31. The process of claim 27 , wherein the bubble plume trajectory is further determined by one or more of the pressure of the conduit having the leak, the depth of the sea, the horizontal distance of the subsea compressor from the inhabited area, the salinity of the sea, the temperature of the water, the density of the components of a first injection stream, the velocity of the water currents, and the leak diameter.

Assignees

• Fieler Eleanor
• Rasmussen Peter C
• Robinson Chris M
• Hissong Douglas W
• Exxonmobil Upstream Res Co

Inventors

• Fieler Eleanor
• Rasmussen Peter C
• Robinson Chris M
• Hissong Douglas W

Classifications

• E21B41/0092 Primary

  Fixed Constructions · mapped topic

• E21B43/40

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

• E21B43/168 Primary

  Injecting a gaseous medium · CPC title