Apparatus and method for subsea liquid mixing and sampling

Patent metadata

Field	Value
Publication number	US-10174866-B2
Application number	US-201515510234-A
Country	US
Kind code	B2
Filing date	Sep 10, 2015
Priority date	Sep 12, 2014
Publication date	Jan 8, 2019
Grant date	Jan 8, 2019

Abstract

A submersible mixing and sampling apparatus with submersible supply systems (12, 14) for first and second liquid components such as a thermoset resin and a curing agent is disclosed. Each supply system has a respective submersible tank (24) for holding a respective one of the liquid components. Submersible mixers (46, 48, 50) downstream of the supply systems mix the liquid components underwater to form a curable mixture for injection into a subsea chamber such as a tee (102). Submersible sampling devices downstream of the mixers take samples (94) of the mixture underwater before, during and after injection, and optionally also at the surface. The samples may be cured and tested underwater or may be lifted to the surface for testing. The apparatus may be mounted on a subsea skid (100) or basket.

First claim

The invention claimed is:

1. A subsea-submersible mixing and sampling apparatus, comprising:
submersible supply systems for first and second liquid components, each supply system comprising a respective submersible reservoir for holding a respective one of those liquid components, wherein the submersible reservoirs of the submersible supply systems are pressure-compensated or collapsible;
at least one submersible mixer downstream of the supply systems for mixing the first and second liquid components to form a mixture for curing;
at least one submersible sampling device downstream of the or each mixer for taking a sample of the mixture underwater; and
at least one injection outlet downstream of at least one of the mixers for injecting the mixture into a subsea chamber to which the injection outlet may be connected in use, wherein the injection outlet and a sampling device are on parallel flowpaths downstream of said mixer.

2. The apparatus of claim 1 , further comprising a sampling valve system downstream of said mixer, which valve system is operable to direct the mixture selectively along either flowpath to the injection outlet or said sampling device.

3. The apparatus of claim 1 , further comprising a bypass line downstream of at least one of the mixers for carrying the mixture past at least one of the sampling devices.

4. The apparatus of claim 3 , further comprising a bypass valve system downstream of said mixer, which valve system is operable to direct the mixture selectively along a sampling line to the sampling device or along the bypass line to bypass the sampling device.

5. The apparatus of claim 1 , comprising a plurality of mixers on respective parallel flowpaths downstream of the supply systems.

6. The apparatus of claim 5 , further comprising a switching valve system upstream of the mixers, which valve system is operable to direct the liquid components selectively to one or more of the mixers.

7. The apparatus of claim 5 , wherein at least one sampling device is downstream of each mixer.

8. The apparatus of claim 1 , further comprising a supply valve system upstream of the mixers, which valve system is operable to direct only one of the liquid components to a mixer and/or to a sampling device.

9. The apparatus of claim 1 , further comprising a submersible slops tank for receiving the liquid components or the mixture from a mixer and/or from a sampling device.

10. The apparatus of claim 1 , wherein at least one of the sampling devices comprises a curing cavity for curing the sample and a closure that is movable to release the cured sample from the curing cavity.

11. A subsea skid or basket carrying the apparatus of claim 1 .

12. A subsea structure having a chamber coupled to the skid or basket of claim 11 .

13. The subsea structure of claim 12 , wherein the subsea chamber is connected on an upstream side to the injection outlet and on a downstream side to a sampling inlet; a sampling device is downstream of the sampling inlet to receive the mixture from the subsea chamber; and the sampling device is in series with the injection outlet on the same flowpath.

14. A method of mixing and sampling liquids underwater, comprising:
separately supplying liquid components from separate subsea reservoirs underwater, those components being a thermoset resin and a curing agent;
mixing the liquid components underwater to form a mixture for curing;
providing the mixture to an injection outlet and a sampling device, the injection outlet and the sampling device being on parallel flowpaths;
taking a sample of the mixture underwater; and
injecting the mixture into a subsea chamber to which the injection outlet is connected,
wherein the method comprises compensating the subsea reservoirs against hydrostatic pressure or allowing the subsea reservoirs to collapse under hydrostatic pressure.

15. The method of claim 14 , comprising curing the sample underwater.

16. The method of claim 15 , comprising testing the cured sample underwater.

17. The method of claim 15 , comprising transporting the cured sample to the surface.

18. The method of claim 14 , comprising taking a sample of the mixture before, during and/or after injecting the mixture into a subsea chamber.

19. The method of claim 14 , preceded by supplying and mixing the liquid components above the water surface to form a mixture and taking a sample of the mixture above the water surface.

20. The method of claim 18 , comprising switching the liquid components from one mixer to another mixer between one sampling operation and another sampling operation.

21. The method of claim 14 , comprising taking a sample of either of the liquid components underwater.

22. The method of claim 21 , comprising taking a sample of a liquid component after that component has passed through a mixer.

23. The method of claim 18 , comprising switching the mixture or one of the liquid components from one sampler to another sampler between one sampling operation and another sampling operation.

24. The method of claim 14 , comprising flushing one of the liquid components through a mixer, a sampler or a flowpath that carried the mixture.

25. The method of claim 14 , comprising capturing an excess of the liquid components or of the mixture underwater after mixing, sampling or flushing and containing that captured excess while underwater.

26. A subsea structure having a chamber coupled to the apparatus of claim 1 .

27. The subsea structure of claim 26 , wherein the subsea chamber is connected on an upstream side to the injection outlet and on a downstream side to a sampling inlet; a sampling device is downstream of the sampling inlet to receive the mixture from the subsea chamber; and the sampling device is in series with the injection outlet on the same flowpath.

Assignees

• Subsea 7 Ltd

Inventors

• Fowkes Mick
• Booth Paul
• Vu Dan Quoc
• Munro Stewart John Sinclair
• Ogg Catriona Rachel

Classifications

• F16L55/175

  by using materials which fill a space around the pipe before hardening · CPC title

• B29B7/7466

  Combinations of similar mixers · CPC title

• B29K2063/00

  Use of {EP, i.e.} epoxy resins {or derivatives thereof}, as moulding material · CPC title

• B29B7/86

  for working at sub- or superatmospheric pressure {(B01F33/70 takes precedence)} · CPC title

• B29C73/025

  fed under pressure · CPC title