Method and Apparatus for Wet Gas Flow Measurements and Measurement of Gas Properties

• US 20110301877A1
• Filed: 12/14/2009
• Published: 12/08/2011
• Est. Priority Date: 12/12/2008
• Status: Active Grant

• Current Assignee: Fmc Kongsberg Subsea As (TechnipFMC, plc)
• Original Assignee: Fmc Kongsberg Subsea As (TechnipFMC, plc)
• Inventors: Wee, Arnstein, Skjaeldal, Ingve Morten
• Granted Patent: US 9,759,592 B2
• Time in Patent Office: Days
• US Class Current: 702/47
• CPC Class Codes: G01F 1/363 with electrical or electro-mechanical indication G01F1/37 and G01F1/38 take precedence
• 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 1/88 with differential-pressure measurement to determine the volume flow
• CPC Class Codes: G01F 15/022 using electrical means

Abstract

A method for determining the flow rates of a fluid comprising a multi-component mixture of a gas and at least one liquid in a pipe, the method comprising the following steps: a. The temperature and pressure of the multi-component mixture is determined, b. the fractions of the multi-component mixture is determined based on at least two measured physical properties of the multi-components mixture and knowledge of the same physical property of the individual components of the multi-component mixture, c. the velocity of the multi component mixture is determined, d. based on the result from step a-c, the flow rate of the individual component of the fluid is determined, characterized by a method for determining the physical properties of at least one of the components of the multi-component mixture where e. an electromagnetic loss or phase measurement is performed, f. a statistical parameter related to the electromagnetic measurement is calculated, g. the said statistical parameter is compared to an empirical derived threshold value corresponding to the value of the statistical parameter when only one of the component of the multi component mixture is present, and h. the said physical properties of said fluid is determined if the statistical parameter exceeds the threshold value for the said component and used in step b-d to provide an improved value of the fractions, velocity and flow rate of the individual components of the multi-component mixture. An apparatus for performing the method is also disclosed.

Claims

1-33. -33. (canceled)

34. A method for determining the flow rates of a fluid comprising a multi-component mixture of a gas and at least one liquid in a pipe, the method comprising the following steps:

a. determining the temperature and pressure of the multi-component mixture,

b. determining the fractions of the multi-component mixture based on at least two measured physical properties of the multi-components mixture and knowledge of the same physical property of the individual components of the multi-component mixture,

c. determining the velocity of the multi component mixture,

d. determining the flow rate of the individual component of the fluid, based on the result from step a-c

whereby determining the physical properties of at least one of the components of the multi-component mixture, including

e. performing an electromagnetic loss or phase measurement,

f. calculating a statistical parameter related to the electromagnetic measurement,

g. determining when only one of the component of the multi component mixture is present,

h. comparing the said statistical parameter to an empirical derived threshold value corresponding to the value of the statistical parameter, and

i. determining the said physical properties of said fluid if the statistical parameter below the threshold value for the said component, and using said physical properties in step b-d to determine an improved value of the fractions, velocity and flow rate of the individual components of the multi-component mixture.

35. A method according to claim 34, wherein the physical property is mass absorption coefficient.

36. A method according to claim 34, wherein the measured physical property is permittivity.

37. A method according to claim 34, wherein the measured physical property is density.

38. A method according to claim 34, wherein the measured physical property is mass attenuation.

39. A method according to claim 34, wherein the measured physical property is conductivity.

40. A method according to claim 34 wherein the velocity is measured based measurement of pressure drop across a restriction in the pipe.

41. A method according to claim 40, wherein a venturi is used to provide pressure drop.

42. A method according to claim 40, wherein a V-cone is used to provide pressure drop.

43. A method according to claim 40, wherein a Dall tube is used to provide pressure drop.

44. A method according to claim 40, wherein a orifice is used to provide pressure drop.

45. A method according to claim 34, wherein cross-correlation techniques are used in determining the velocity of the multi-component mixture.

46. A method according to claim 34, wherein the electromagnetic measurement is based on measurement of the phase or loss of an electromagnetic wave transmitted through the media within the pipe.

47. A method according to claim 34, wherein the electromagnetic measurement is based on measurement of the phase or loss of a reflected electromagnetic wave within the pipe.

48. A method according to claim 34, wherein the electromagnetic measurement is based on measurement of a resonance frequency within the pipe.

49. A method according to claim 34, wherein the electromagnetic measurement is based on measurement of energy loss and/or phase shift of an electromagnetic wave being reflected from the media within the pipe.

50. A method for determining the flow rates of a fluid comprising a multi-component mixture of a gas and at least one liquid in a pipe, the method comprising the following steps:

a. determining the temperature and pressure of the multi-component mixture,

b. determining the fractions of the multi-component mixture based on at least two measured physical properties of the multi-components mixture and knowledge of the same physical property of the individual components of the multi-component mixture,

c. determining the velocity of the multi component mixture,

d. determining the flow rate of the individual component of the fluid, based on the result from step a-c

where by determining the physical properties of at least one of the components of the multi-component mixture, including

e. performing an electromagnetic loss or phase measurement,

f. calculating a statistical parameter related to the electromagnetic measurement,

g. determining when only one of the component of the multi component mixture is present,

h. comparing the said statistical parameter to an empirical derived threshold value corresponding to the value of the statistical parameter, and

determining the said physical properties of said fluid if the statistical parameter below the threshold value for the said component, and using said physical properties in step b-d to determine an improved value of the fractions, velocity and flow rate of the individual components of the multi-component mixture, wherein the statistical parameter is calculate from claim 46.

51. A method according to claim 34, wherein the standard deviation is used as the statistical parameter.

52. An apparatus for determining the flow rates of a fluid comprising a multi-component mixture of a gas and at least one liquid in a pipe, the apparatus comprising a tubular section and the following elements:

a. means for determining the temperature and pressure of the multi-component mixture,

b. means for measuring at least two physical quantities of the multi-component mixture,

c. means for calculating the fractions of the individual components of the multi-component mixture based on knowledge of the said physical properties of the individual components of the multi-component mixture,

d. means for determining the velocity of the multi component mixture,

e. means for calculating the flow rate of the individual fractions of the multi-component mixture,

wherein a means for determining the physical properties of at least one of the components of the multi-component mixture, comprising

f. means for performing an electromagnetic loss or phase measurement,

g. means for calculating a statistical parameter based on the electromagnetic measurement,

h. means for determining when only one of the components of the multi-component mixture is present,

i. means for comparing the statistical parameter towards an empirical determined threshold value, and

j. means for measuring a physical quantity of at least one of the components of the multi-component mixture.

53. An apparatus according to claim 52, comprising means for transmitting electromagnetic energy into the tubular section and recording received electromagnetic energy from the tubular section.

54. An apparatus according to claim 52, comprising means for providing electromagnetic resonances within the tubular section.

55. An apparatus according to claim 52, comprising means for transmitting electromagnetic energy into the tubular section and recording reflected electromagnetic energy from the tubular section.

56. An apparatus according to claim 52, comprising means for measuring said velocity in a narrow passage of the tubular section.

57. An apparatus according to claim 52, wherein a venturi is used to determine said velocity.

58. An apparatus according to claim 52, wherein a V-cone is used to determine said velocity.

59. An apparatus according to claim 52, comprising means for measuring said velocity by cross-correlating measurements performed in two cross-sections of the tubular sections.

60. An apparatus according to claim 52, comprising a radioactive source and photon detector for measurement of physical quantities of the multi-component mixture.

61. An apparatus according to claim 52, comprising multiple pressure drop measurements for measurement of physical quantities of the multi-component mixture.

62. An apparatus according to claim 52, comprising a combination of a pressure drop device and cross correlation velocity device for measurement of physical quantities of the multi-component mixture.