Multiphase separation system

Patent metadata

Field	Value
Publication number	US-9314715-B2
Application number	US-201514683854-A
Country	US
Kind code	B2
Filing date	Apr 10, 2015
Priority date	Apr 29, 2014
Publication date	Apr 19, 2016
Grant date	Apr 19, 2016

Abstract

The current disclosure relates to multiphase fluid separation via a multiphase separation system. The multiphase separation system is configured to feed a multiphase fluid into feed lines within the multiphase separation system, wherein the feed lines consist of an upper line, a middle line, and a lower line. The upper line is configured to flow a first stream substantially including oil into an oil section of a control volume. The middle line is configured to flow a second stream substantially including an oil/water emulsion into an oil/water emulsion section of the control volume. The lower line is configured to flow a third stream substantially including water into a water section of the control volume. The control volume is configured to adjust fluid flow rate at an outlet, wherein the oil section, the water section, and the oil/water emulsion section each commingle at different heights of the control volume.

First claim

What is claimed is:

1. A multiphase separation system, comprising:
a distribution line configured to feed a multiphase fluid into feed lines within the separation system, wherein the feed lines consist of an upper line, a middle line, and a lower line;
the upper line configured to flow a first stream comprising oil into an oil section of a control volume;
the middle line configured to flow a second stream comprising an oil/water emulsion into an oil/water emulsion section of the control volume;
the lower line configured to flow a third stream comprising water into a water section of the control volume; and
the control volume configured to adjust fluid flow rate at an outlet, wherein the oil section, the water section, and the oil/water emulsion section each commingle at different heights of the control volume.

2. The multiphase separation system of claim 1 , wherein the separation system is implemented within a subsea environment, and the multiphase fluid comprises production fluids from a subsea well.

3. The multiphase separation system of claim 1 , wherein the upper line, middle line, and lower line are parallel to each other, and perpendicular to the control volume.

4. The multiphase separation system of claim 1 , wherein flow rate at an inlet at the control volume is adjusted through use of a control valve at the upper line upstream of the control volume and a control valve at the lower line upstream of the control volume.

5. The multiphase separation system of claim 1 , wherein the control volume is configured to flow fluid at an outlet at the top of the control volume, and wherein the fluid flow out of the outlet at the top of the control volume comprises substantially oil.

6. The multiphase separation system of claim 1 , wherein the control volume is configured to flow fluid at an outlet at the bottom of the control volume, and wherein the fluid flow of the outlet at the bottom of the control volume comprises substantially water.

7. The multiphase separation system of claim 1 , wherein the control volume is configured to flow fluid at an outlet at the middle of the control volume, and wherein the fluid flow of the outlet at the middle of the control volume comprises an oil/water emulsion.

8. The multiphase separation system of claim 1 , further comprising a flow regulator in the upper line, the middle line, and the lower line, and wherein the flow regulator comprises a perforated baffle, an adjustable perforated baffle, a gate valve, or any combination thereof.

9. The multiphase separation system of claim 8 , further comprising:
a control system configured to adjust open and closed the flow regulator;
a level detector coupled to the upper line, the middle line, or the lower line, wherein the level detector is adapted to measure a phase interface level of water and oil present in a line.

10. The multiphase separation system of claim 1 , wherein the upper line, middle line, lower line, or any combination thereof are further configured for a chemical additive to be injected.

11. The multiphase separation system of claim 10 , wherein the chemical additive that is injected comprises defoamers or demulsifiers.

12. The multiphase separation system of claim 1 , wherein any of the upper line, middle line, or lower line are coupled to an electrostatic coalescer.

13. The multiphase separation system of claim 1 , wherein any of the upper line, middle line, lower line, or any combination thereof are configured with droplet coalescing internals.

14. The multiphase separation system of claim 1 , further comprising:
a downcomer coupled to the lower line, wherein the downcomer is sealed by a sand boot, and wherein the sand boot is configured with internals to fluidize and remove sand that has accumulated in the sand boot; or
a recycle line coupled to the lower line, wherein the recycle line is configured to fluidize and remove sand that has accumulated, and wherein the recycle line is configured to be on an exterior of the oil section, the water section, or the oil/water emulsion section.

15. The multiphase separation system of claim 1 , wherein a pre-separator is utilized upstream of the separation system, and wherein the pre-separator is configured to separate gas from the multiphase fluid.

16. The multiphase separation system of claim 1 , wherein an outlet from the control volume is configured to recycle upstream into the upper line, middle line, or lower line.

17. The multiphase separation system of claim 1 , further comprising a polishing section, wherein a side draw is coupled from the upper line to the middle line, and a side draw is coupled from the middle line to the lower line.

18. The multiphase separation system of claim 1 , further comprising:
a first downcomer/riser apparatus configured to permit the passage of oil from the lower line, the middle line, or both to the upper line, wherein the first downcomer/riser apparatus is further configured to permit the passage of water from the upper line, the middle line, or both to the lower line, and wherein the first downcomer/riser apparatus is further configured to substantially inhibit all other exchanges of fluid between the upper line, the middle line, and the lower line;
a second downcomer/riser apparatus configured to permit the passage of oil from the lower line to the upper line and permit the passage of water from the upper line to the lower line, wherein the second downcomer/riser apparatus is further configured to substantially inhibit all other exchanges of fluid between the upper line, the middle line, and the lower line; or
both the first downcomer/riser apparatus and the second downcomer/riser apparatus.

19. A method for separation of oil and water and oil/water emulsion within a multiphase fluid, comprising:
flowing a multiphase fluid into a distribution inlet of a multiphase separation system;
separating the multiphase fluid into an oil phase, a water phase, and an oil/water emulsion;
separating the oil phase into a line that is in a plane vertically above the plane of the distribution inlet;
separating the water phase into a line that is in a plane vertically below the plane of the distribution inlet;
separating the oil/water emulsion into a line that is in a plane vertically above the plane of the line with the water phase and vertically below the plane of the line with the oil phase;
flowing each line into a vertically oriented control volume, wherein the flow rate from each line is controlled;
detecting an oil level and a water level in each line,
communicating with a controller to open and close control valves based on the oil and water level detected; and
separating each phase by flowing the oil phase, the water phase, and the oil/water emulsion through a different outlet from the control volume.

20. The method of claim 19 , comprising regulating the flow rate of the fluid in a line through use of perforated baffles, through adjustment of an adjustable perforated baffle, through use of a gate valve, or any combination thereof.

21. The method of claim 19 , further comprising injecting chemical additives into the oil line, water line, and oil/water emulsion line.

22. The method of claim 19 , further comprising:
accumulating sand in an additional hollow space of the water line; and
purging sand from the water line.

23. The method of claim 19 , further comprising removing dispersed droplets from the bulk phase flowing in an oil line, water line, and oil/water emulsi

Assignees

• Grave Edward J
• Bymaster Adam S
• Olson Michael D
• Larnholm Per-Reidar
• Whitney Scott M
• Exxonmobil Upstream Res Co

Inventors

• Grave Edward J
• Bymaster Adam S
• Olson Michael D
• Larnholm Per-Reidar
• Whitney Scott M

Classifications

• B01D17/12

  Auxiliary equipment particularly adapted for use with liquid-separating apparatus, e.g. control circuits · CPC title

• B01D17/045 Primary

  with coalescers · CPC title

• B01D17/00

  Separation of liquids, not provided for elsewhere, e.g. by thermal diffusion (devices for separating or removing fatty or oily substances or similar floating material from water, waste water, or sewage C02F1/40; cleaning or keeping clear the surface of open water from oil or like materials E02B15/04; arrangements for separating lubricants from refrigerants F25B43/02) · CPC title

• B01D17/04 Primary

  Breaking emulsions · CPC title

• E21B43/35

  specially adapted for separating solids (down-hole drilling fluid separation systems E21B21/002; separating solids from drilling fluids E21B21/065) · CPC title