System and method to measure salinity of multi-phase fluids

Patent metadata

Field	Value
Publication number	US-2016131601-A1
Application number	US-201514936850-A
Country	US
Kind code	A1
Filing date	Nov 10, 2015
Priority date	Nov 10, 2014
Publication date	May 12, 2016
Grant date	—

Abstract

A method of determining salinity of multi-phase fluids in a conduit includes exciting a sensing device to cause emission of electromagnetic waves of one or more frequencies into the multi-phase fluid. The method includes receiving transmitted or reflected electromagnetic waves from the multi-phase fluid. Furthermore, the method includes determining an intermediate parameter from the received electromagnetic waves. The method also includes obtaining estimated values of a plurality of parameters from the intermediate parameter. The estimated values comprise at least one of an estimated value of conductance, an estimated value of susceptance, an estimated value of differential conductance, an estimated value of differential susceptance, an estimated value of a real part of complex permittivity, and an estimated value of an imaginary part of complex permittivity. Salinity of the fluid is determined based, at least in part, on the estimated values of the plurality of parameters.

First claim

1 . A method of determining salinity of a multi-phase fluid in a conduit, comprising:
exciting a sensing device to cause the sensing device to emit electromagnetic waves of one or more frequencies into a multi-phase fluid, wherein the sensing device is placed proximate to the multi-phase fluid; receiving at least one of transmitted and reflected electromagnetic waves from the multi-phase fluid; determining an intermediate parameter from the transmitted or reflected electromagnetic waves; obtaining estimated values of at least one of a plurality of parameters from at least one of the transmitted and reflected electromagnetic waves, wherein the estimated values of plurality of parameters comprise at least one of an estimated value of conductance, an estimated value of susceptance, an estimated value of differential conductance, an estimated value of differential susceptance, an estimated value of a real part of complex permittivity, and an estimated value of an imaginary part of complex permittivity; and determining the salinity of the multi-phase fluid based, at least in part, on the plurality of parameters.

2 . The method of claim 1 , further comprising computing a first ratio between the estimated value of the imaginary part of complex permittivity and the estimated value of the real part of complex permittivity.

3 . The method of claim 2 , further comprising:
obtaining computed values of the real and imaginary parts of complex permittivity using a feed-forward model by iteratively changing salinity values for the multi-phase fluid, wherein the feed-forward model comprises a relationship between the real and imaginary parts of the complex permittivity, the one or more frequencies, temperature of the multi-phase fluid, and the salinity of the multi-phase fluid; comparing the first ratio and a second ratio between the computed value of the imaginary part of complex permittivity and the computed value of the real part of complex permittivity; and selecting a particular salinity value as the salinity of the multi-phase fluid when the difference between the first ratio and the second ratio is less than a first threshold.

4 . The method of claim 2 , further comprising:
identifying one or more records from a data repository corresponding to the first ratio, wherein each record corresponds to a particular value of salinity of the multi-phase fluid for a particular value of the first ratio; and estimating the salinity of the multi-phase fluid based on the one or more records from the data repository.

5 . The method of claim 1 , further comprising:
identifying one or more records from a data repository corresponding to a third ratio between the estimated values of conductance and susceptance, wherein each record corresponds to a particular value of salinity of the multi-phase fluid for a particular value of the third ratio; and estimating the salinity of the multi-phase fluid based on the one or more records from the data repository.

6 . The method of claim 1 , further comprising:
identifying one or more records from a data repository corresponding to a fourth ratio between the estimated values of differential conductance and differential susceptance, wherein each record corresponds to a particular value of salinity of the multi-phase fluid for a particular value of the fourth ratio; and estimating the salinity of the multi-phase fluid based on the one or more records from the data repository.

7 . The method of claim 1 , wherein the plurality of intermediate parameters comprise at least a complex reflection coefficient associated with the transmitted or reflected electromagnetic waves.

8 . The method of claim 1 , wherein exciting the sensing device comprises exciting a coaxial probe.

9 . A system for determining salinity of a multi-phase fluid flowing in a conduit, the system comprising:
a sensing device placed on or about the conduit and configured to emit electromagnetic waves of one or more frequencies; and a controller configured to
excite the sensing device to emit electromagnetic waves of the one or more frequencies towards the multi-phase fluid,
acquire at least one of transmitted and reflected electromagnetic waves corresponding to the one or more frequencies from the multi-phase fluid,
obtain estimated values of at least one of a plurality of parameters from at least one of the transmitted and reflected electromagnetic waves, wherein estimated values of the plurality of parameters comprise at least one of an estimated value of conductance, an estimated value of susceptance, an estimated value of differential conductance, an estimated value of differential susceptance, an estimated value of a real part of complex permittivity, and an estimated value of an imaginary part of complex permittivity, and
determine the salinity of the multi-phase fluid based, at least in part, upon at least one of the plurality of parameters.

10 . The system of claim 9 , wherein the sensing device comprises at least one of a patch antenna, a coaxial probe, a monopole antenna, a dipole antenna, an antenna feed, or a multi pole antenna.

11 . The system of claim 9 , wherein the controller is configured to determine a plurality of intermediate parameters from the transmitted or reflected electromagnetic waves.

12 . The system of claim 11 , wherein the plurality of intermediate parameters comprise at least one of a complex reflection coefficient and a complex transmission coefficient associated with the transmitted and reflected electromagnetic waves.

13 . The system of claim 10 , further comprising a dielectric layer placed proximate to the sensing device such that one side of the dielectric layer is in direct contact with the multi-phase fluid when the sensing device comprises patch antenna.

14 . The system of claim 13 , wherein the side of the dielectric layer that is in direct contact with the multi-phase fluid is configured to conform to a shape of an inner surface of the conduit.

15 . The system of claim 9 , wherein the controller is further configured to:
obtain computed values of the real and the imaginary part of complex permittivity using a feed-forward model by iteratively changing salinity values for the multi-phase fluid, wherein the feed-forward model comprises a relationship between the real and imaginary parts of complex permittivity, the one or more frequencies, temperature of the multi-phase fluid, and the salinity of the multi-phase fluid; compare a first ratio between the estimated value of the imaginary part of complex permittivity and the estimated value of the real part of complex permittivity and a second ratio between the computed value of the imaginary part of complex permittivity and the computed value of the real part of complex permittivity; and select a particular salinity value as the salinity of the multi-phase fluid when the difference between the first ratio and the second ratio is less than a first threshold.

16 . The system of claim 9 , wherein the controller is further configured to extract one or more records pertaining to a relationship between different values of salinity of the multi-phase fluid and at least one of
a first ratio of the estimated value of imaginary part of complex permittivity and the estimated value of real part of complex permittivity for the one or more frequencies; a third ratio between the estimated value of conductance and the estimated value of susceptance; and a fourth ratio between the estimated value of differential conductance and the estimated value of differential susceptance.

17 . The syst

Assignees

• Gen Electric

Inventors

• Sharma Prafull
• Sheila-Vadde Aparna Chakrapani

Classifications

• G01N22/00 Primary

  Investigating or analysing materials by the use of microwaves or radio waves, i.e. electromagnetic waves with a wavelength of one millimetre or more (G01N3/00 - G01N17/00, G01N24/00 take precedence) · CPC title

• G01N33/2823

  Raw oil, drilling fluid or polyphasic mixtures · CPC title

• G01N33/0004

  Gaseous mixtures, e.g. polluted air · CPC title

• G01N27/06

  of a liquid (involving electrolysis G01N27/26) · CPC title