Process control systems and methods for simultaneous crude oil dehydration, desalting, sweetening, and stabilization with indirect recycle heating

Patent metadata

Field	Value
Publication number	US-12037550-B2
Application number	US-202318343897-A
Country	US
Kind code	B2
Filing date	Jun 29, 2023
Priority date	May 25, 2021
Publication date	Jul 16, 2024
Grant date	Jul 16, 2024

Abstract

Systems and methods for crude oil separations including degassing, dewatering, desalting, and stabilization, one method including separating crude oil into a crude oil off-gas and a partially degassed crude oil output; compressing the crude oil off-gas; applying the compressed crude oil off-gas for indirect heating of the partially degassed crude oil output; further heating the partially degassed crude oil output indirectly with compressed low pressure gas; directly mixing with the partially degassed crude oil output a compressed atmospheric pressure gas; separating from the partially degassed crude oil output a low pressure gas for use in the step of further heating; and separating from the partially degassed crude oil output an atmospheric pressure gas for use in the step of directly mixing.

First claim

What is claimed is:

1. An integrated gas oil separation method, the method comprising the steps of:
separating crude oil into a crude oil off-gas and a partially degassed crude oil output;
compressing the crude oil off-gas to produce compressed crude oil off-gas;
applying the compressed crude oil off-gas for indirect heating of the partially degassed crude oil output;
further heating the partially degassed crude oil output indirectly with compressed low pressure gas;
directly mixing with the partially degassed crude oil output a compressed atmospheric pressure gas;
separating from the partially degassed crude oil output a low pressure gas for use in the step of further heating; and
separating from the partially degassed crude oil output an atmospheric pressure gas for use in the step of directly mixing.

2. The method according to claim 1 , further comprising the steps of removing from the low pressure gas gas condensates and water after the low pressure gas is cooled in the step of further heating, and supplying a portion of the low pressure gas to be compressed in the step of compressing the crude oil off-gas.

3. The method according to claim 2 , wherein the step of removing from the low pressure gas gas condensates and water after the low pressure gas is cooled comprises the use of a low pressure knockout drum (KOD).

4. The method according to claim 1 , further comprising the steps of removing from the crude oil off-gas gas condensates and water after the crude oil off-gas is cooled in the step of applying, and supplying a portion of the crude oil off-gas to a natural gas treatment facility.

5. The method according to claim 4 , wherein the step of removing from the crude oil off-gas gas condensates and water after the crude oil off-gas is cooled comprises the use of a high pressure KOD.

6. The method according to claim 1 , wherein the compressed atmospheric pressure gas comprises off-gas from a crude oil stabilizer with reboilers.

7. The method according to claim 1 , wherein the compressed atmospheric pressure gas comprises off-gas from a treated crude oil export product tank.

8. The method according to claim 1 , wherein the compressed atmospheric pressure gas comprises atmospheric off-gas from a crude oil stabilizer without reboilers and with a stripping gas injection stream.

9. The method according to claim 8 , where the stripping gas injection stream is operable to supply steam in addition to or alternative to an additional stripping gas lower in H 2 S concentration relative to crude oil in the crude oil stabilizer, where the stripping gas stream is operable to lower concentration of H 2 S in the crude oil in the crude oil stabilizer.

10. The method according to claim 1 , where the method is operable to refine the crude oil to produce a refined crude oil product for storage and shipment meeting the following specifications: (1) a salt concentration of not more than about 10 pound (lbs.) of salt/1000 barrels (PTB); (2) basic sediment and water (BSW) of not more than about 0.3 volume percent (V %); (3) H 2 S concentration of less than about 60 ppm; and (4) a maximum RVP of about 7 pounds per square inch absolute (psia) and a maximum true vapor pressure (TVP) of about 13.5 psia at 130 degrees Fahrenheit (° F.).

11. The method according to claim 1 , further comprising the step of applying a multi-variable prediction controller to control variables selected from the group consisting of: a demulsifier injection rate; a wash water injection rate; a wash water recycle rate; a low pressure production trap (LPPT) temperature; LPPT pressure; LPPT oil-in-water emulsion level; a low pressure degassing tank (LPDT) temperature; LPDT pressure; and LPDT oil-in-water emulsion level; and
where the method is operable to refine crude oil in the crude oil inlet feed stream to produce a refined crude oil product for storage and shipment meeting the following specifications: (1) a salt concentration of not more than about 10 pound (lbs.) of salt/1000 barrels (PTB); (2) basic sediment and water (BSW) of not more than about 0.3 volume percent (V %); (3) H 2 S concentration of less than about 60 ppm; and (4) a maximum RVP of about 7 pounds per square inch absolute (psia) and a maximum true vapor pressure (TVP) of about 13.5 psia at 130 degrees Fahrenheit (° F.).

12. The method according to claim 1 , wherein the step of separating from the partially degassed crude oil output a low pressure gas comprises the use of a LPPT and where the step of separating from the partially degassed crude oil output an atmospheric pressure gas comprises the use of a LPDT, and wherein the operating pressure within the LPPT is greater than operating pressure in the LPDT.

13. The method according to claim 1 , further comprising the step of flowing a degassed crude oil product through a crude oil charge pump, a trim heater, and a desalter following the step of separating from the partially degassed crude oil output an atmospheric pressure gas.

14. The method according to claim 1 , wherein the step of separating crude oil into a crude oil off-gas and a partially degassed crude oil output comprises the use of an inline cyclonic separator operating at a pressure between about 50 psig and about 150 psig greater than an operating pressure of an LPPT in the step of separating from the partially degassed crude oil output the low pressure gas.

15. The method according to claim 1 , wherein the step of separating from the partially degassed crude oil output a low pressure gas comprises the use of an LPPT, wherein the step of separating from the partially degassed crude oil output an atmospheric pressure gas comprises the use of an LPDT, and wherein the LPPT and LPDT comprise an inlet cyclonic separator, insulated electrostatic electrodes, and a weir, wherein oil-in-water emulsions are disposed proximate the weirs during operation.

16. The method according to claim 1 , wherein the compression of gasses does not require after cooling.

Assignees

• Saudi Arabian Oil Co

Inventors

• Soliman Mohamed

Classifications

• B01D17/045

  with coalescers · CPC title

• C10G33/08

  Controlling or regulating · CPC title

• C10G33/02

  with electrical or magnetic means · CPC title

• C10G31/08

  by treating with water · CPC title

• C10G2300/4012

  Pressure · CPC title