MULTIPHASE FLOW MEASUREMENT SYSTEM

• US 20020033043A1
• Filed: 09/19/2001
• Published: 03/21/2002
• Est. Priority Date: 10/28/1999
• Status: Active Grant

• Current Assignee: Chad Steele, Robert E. Dutton
• Original Assignee: Chad Steele, Robert E. Dutton
• Inventors: Dutton, Robert E., Steele, Chad
• Granted Patent: US 6,564,619 B2
• Time in Patent Office: Days
• US Class Current: 73/61.44
• CPC Class Codes: E21B 49/0875 determining specific fluid parameters
• CPC Class Codes: G01F 1/74 Devices for measuring flow of a fluid or flow of a fluent solid material in suspension in another fluid
• CPC Class Codes: G01F 1/84 Coriolis or gyroscopic mass flowmeters
• CPC Class Codes: G01F 15/08 Air or gas separators in combination with liquid meters; Liquid separators in combination with gas-meters
• CPC Class Codes: G01N 9/002 using variation of the resonant frequency of an element vibrating in contact with the material submitted to analysis G01N9/34 takes precedence

Abstract

A method and system of performing multiphase flow measurements. The method includes separating an incoming multiphase flow into a majority liquid component and a majority gas component. The majority liquid component comprises a water component and an oil component. The method further includes determining if the majority liquid component includes entrained gas. If the majority liquid component is substantially free from entrained gas, then the method further includes determining a water cut of the majority liquid component, determining a density of the majority liquid component using a Coriolis flowmeter, and processing the water cut and the density of the majority liquid component to determine a density of the oil component.

Claims

1. A method of performing multiphase flow measurements in flow environments including a liquid phase and a gas phase, said method comprising:

separating an incoming multiphase flow into a majority liquid component and a majority gas component, said majority liquid component comprising a water component and an oil component;

determining if said majority liquid component includes entrained gas; and

if said majority liquid component is substantially free from said entrained gas, then;

determining a water cut of said majority liquid component;

determining a density of said majority liquid component using a Coriolis flowmeter; and

processing said water cut and said density of said majority liquid component to determine a density of said oil component.

2. The method of claim 1 further comprising:

determining a density of said water component; and

processing said density of said water component, said water cut, and said density of said majority liquid component to determine said density of said oil component.

3. The method of claim 2 further comprising:

capturing a sample of said water component using a water trap.

4. The method of claim 3 wherein determining said density of said water comprises:

measuring said density of said water component from said sample using a hydrometer.

5. The method of claim 1 wherein separating said incoming multiphase flow comprises:

separating said incoming multiphase flow into said majority liquid component and said majority gas component using a vortex separator.

6. The method of claim 1 wherein determining if said majority liquid component includes entrained gas comprises:

calculating a drive gain of said Coriolis flowmeter; and

determining if said drive gain is less than a threshold value.

7. The method of claim 1 wherein determining said water cut of said majority liquid component comprises:

measuring said water cut using a microwave-based monitor.

8. The method of claim 1 wherein determining said water cut of said majority liquid component comprises:

measuring said water cut using a infrared-based monitor.

9. The method of claim 1 wherein determining said water cut of said majority liquid component comprises:

measuring said water cut using a capacitive-based monitor.

10. The method of claim 1 wherein determining said water cut of said majority liquid component comprises:

measuring said water cut using a resistance-based monitor.

11. The method of claim 1 further comprising:

after determining said density of said oil component, measuring a flow rate of said oil component based on said density of said oil component, wherein said majority liquid component includes said entrained gas.

13. The multiphase flow measurement system of claim 12 wherein said controller is further configured to:

receive a density of said water component; and

process said density of said water component, said water cut, and said density of said majority liquid component to determine said density of said oil component.

14. The multiphase flow measurement system of claim 12 further comprising:

a water trap configured to receive said majority liquid component and capture a sample of said water component.

15. The multiphase flow measurement system of claim 13 further comprising:

a hydrometer configured to determine said density of said water component from said sample.

16. The multiphase flow measurement system of claim 12 wherein:

said separator comprises a vortex separator.

17. The multiphase flow measurement system of claim 12 wherein said controller determines if said majority liquid component includes said entrained gas by being further configured to:

calculate a drive gain of said Coriolis flowmeter; and

determine if said drive gain is less than a threshold value.

18. The multiphase flow measurement system of claim 12 wherein said water cut monitor comprises:

a microwave-based monitor.

19. The multiphase flow measurement system of claim 12 wherein said water cut monitor comprises:

an infrared-based monitor.

20. The multiphase flow measurement system of claim 12 wherein said water cut monitor comprises:

a capacitive-based monitor.

21. The multiphase flow measurement system of claim 12 wherein said water cut monitor comprises:

a resistance-based monitor.

22. The multiphase flow measurement system of claim 12 wherein said controller is further configured to:

measure a flow rate of said oil component based on said density of said oil component, wherein said majority liquid component includes said entrained gas.

12. A multiphase flow measurement system for performing multiphase flow measurements in flow environments including a liquid phase and a gas phase, said multiphase flow measurement system comprising:

a separator configured to separate an incoming multiphase flow into a majority liquid component and a majority gas component, said majority liquid component comprising a water component and an oil component;

a Coriolis flowmeter configured to receive said majority liquid component and determine a density of said majority liquid component;

a water cut monitor configured to receive said majority liquid component and determine a water cut of said majority liquid component; and

a controller configured to communicate with said Coriolis flowmeter and said water cut monitor, determine if said majority liquid component includes entrained gas, and if said majority liquid component is substantially free from said entrained gas, then said controller is further configured to process said water cut and said density of said majority liquid component to determine a density of said oil component.