CONFIGURATIONS AND METHODS OF DEWATERING CRUDE OIL

• US 20150344789A1
• Filed: 06/01/2015
• Published: 12/03/2015
• Est. Priority Date: 05/30/2014
• Status: Active Grant

• Current Assignee: Fluor Technologies Corporation (Fluor Corporation)
• Original Assignee: Fluor Technologies Corporation (Fluor Corporation)
• Inventors: Rodwell, Morgan Charles
• Granted Patent: US 10,640,716 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: C10G 33/06 with mechanical means, e.g. by filtration
• CPC Class Codes: C10G 33/08 Controlling or regulating
• CPC Class Codes: C10G 7/04 Dewatering

Abstract

A process for dewatering crude oil is described. The process includes feeding crude oil onto a separation of a cyclone separator that is at least partially disposed in a flash vessel. The temperature are pressure in the flash vessel are selected such that at least 20% of the water contained in the crude oil is flashed from the crude oil as it moves on the separation surface of the cyclone separator. The flow rate and angle of the crude oil inlet is selected such that the crude oil moves across the separation surface as a film in a helical pattern, providing a substantial foaming-free manner. The vapor that is flashed from the crude oil exits the flash vessel at a top outlet and the liquid crude oil exits the flash vessel at a bottom outlet.

Claims

1. A method of water removal from crude oil, comprising:

feeding the crude oil at a flow rate and a temperature onto a separation surface of a cyclone separator, wherein the cyclone separator is at least partially disposed within a flash vessel;

flashing at least 20% of the water contained in the crude oil as steam from the crude oil while the crude oil is moving on the separation surface; and

wherein the separation surface, a pressure in the flash vessel, the temperature of the crude oil in the separator, and the flow rate are selected such as to allow flashing of the water as steam from the crude oil without foam carry-over into a vapor phase leaving the flash vessel.

2. The method of claim 1, wherein the flash vessel has a crude oil inlet for feeding the crude oil onto the separation surface.

3. The method of claim 2, wherein the flash vessel has a liquid outlet that is located below the crude oil inlet.

4. The method of claim 2, wherein the flash vessel has a vapor outlet that is located above the crude oil inlet.

5. The method of claim 1, wherein the step of flashing is performed under a condition that allows substantially foaming-free flashing.

6. The method of claim 5, wherein the separation surface, the pressure in the flash vessel, the temperature of the crude oil in the separator, and the flow rate are selected such as to allow flashing of at least 70% of water as steam from the crude oil in the flash vessel.

7. The method of claim 1 wherein the separation surface, the pressure in the flash vessel, the temperature of the crude oil in the separator, and the flow rate are selected such as to allow flashing of at least 90% of water as steam from the crude oil in the flash vessel.

8. The method of claim 1, further comprising the steps of:

condensing the vapor phase leaving the flash vessel to form liquid water, some light hydrocarbon liquid, and a hydrocarbon vapor; and

separating the liquid water, the light hydrocarbon liquid, and the hydrocarbon vapor.

9. A water removal unit for treatment of crude oil, comprising:

a flash vessel having a crude oil inlet, a liquid outlet, and a steam outlet;

a cyclone separator having separation surface, wherein the cyclone separator is at least partially disposed within the flash vessel, wherein the crude oil inlet is configured to provide the crude oil at a flow rate onto the separation surface;

a control unit operationally coupled to the flash vessel and programmed to regulate at least one of a temperature in the flash vessel, the flow rate, and a pressure in the flash vessel such as to allow flashing of the crude oil in the flash vessel; and

wherein the separation surface is selected and the control unit is programmed such that the pressure in the flash vessel, the temperature, and the flow rate enable flashing of at least 20% of water as steam from the crude oil on the separation surface.

10. The water removal unit of claim 9, wherein at least part of an outer wall of the cyclone separator forms an outer wall of the flashing vessel

11. The water removal unit of claim 9, wherein the cyclone separator is internal to the flash vessel.

12. The water removal unit of claim 9, wherein the cyclone separator is a multi-cyclone separator.

13. The water removal unit of claim 9, further comprising a condenser unit coupled to the flash vessel and configured to condense the steam from the vapor phase leaving the flash vessel to thereby produce a hydrocarbon vapor.

14. A method of controlling water removal from crude oil in a flash vessel, comprising:

operationally coupling a control unit to a flash vessel and programming the control unit to regulate at least one of a temperature of the crude oil in the flash vessel, a pressure in the flash vessel, and a flow rate of the crude oil such as to allow flashing of the crude oil in the flash vessel; and

using the control unit to regulate the pressure in the flash vessel, the temperature of the crude oil in the flash vessel, and the flow rate to so enable flashing of at least 50% of water as steam from the crude oil in the flash vessel without foam carry-over into a vapor phase and a liquid phase leaving the flash vessel.

15. The method of claim 14, wherein the flash vessel comprises a multi-cyclone separator at least partially disposed in a lumen of the flash vessel.

16. A method of water removal from crude oil, comprising:

moving the crude oil on a separation surface across a pressure gradient and at a velocity and angle that are sufficient to suppress foam formation; and

wherein the crude oil has a temperature sufficient to allow flashing of steam at the pressure gradient.

17. The method of claim 16, wherein the pressure gradient is a pressure drop of at least 10 psig.

18. The method of claim 16, further comprising the step of adjusting at least one of the temperature and the pressure gradient to allow flashing.

19. The method of claim 16, wherein the angle is sufficient for cyclone separation.

20. The method of claim 16, wherein the crude oil moves on the separation surface as a film.

21. The method of claim 20, wherein the film has a thickness of between 1 mm and 20 mm.

22. The method of claim 16, wherein the separation surface is part of a cyclone separator.