Determining fluid properties

Patent metadata

Field	Value
Publication number	US-11525723-B2
Application number	US-202017007405-A
Country	US
Kind code	B2
Filing date	Aug 31, 2020
Priority date	Aug 31, 2020
Publication date	Dec 13, 2022
Grant date	Dec 13, 2022

Abstract

Techniques for measuring fluid properties include circulating a mixed-phase fluid flow through a fluid flow circuit; circulating the mixed-phase fluid flow through a pre-polarizing magnet; polarizing at least a gas phase of the mixed-phase fluid flow to an initial polarization; measuring fluid induction decay (FID) values of the polarized gas phase with the EFNMR detector; determining a velocity of the gas phase based on the FID values of the polarized gas phase; producing a pulsed magnetic field gradient to suppress one or more signals acquired by the EFNMR detector with a first electromagnet; measuring FID values of the liquid phase of the mixed-phase fluid with the EFNMR detector simultaneously with the production of the pulsed magnetic field gradient; producing a homogeneous polarizing field to polarize the liquid phase of the mixed-phase fluid with a second electromagnet; and determining a velocity and content of the liquid phase based on the FID values of the polarized liquid phase.

First claim

What is claimed is:

1. A fluid measurement system, comprising:
a fluid flow circuit that comprises at least two liquid sources, a gas source, and a fluid mixer that mixes at least two liquids from the at least two liquid sources to form a liquid phase of a mixed-phase fluid that also includes a gas phase from the gas source;
a pre-polarizing magnet positioned to receive the mixed-phase fluid flow from the fluid mixer;
an Earth's field nuclear magnetic resonance (EFNMR) detector that comprises a radio-frequency (RF) coil, a first electromagnet aligned with the RF coil, and a second electromagnet downstream of and separate from the first electromagnet, the EFNMR detector positioned to receive the mixed-phase fluid from the pre-polarizing magnet; and
a control system communicably coupled to the pre-polarizing magnet and the EFNMR detector and configured to perform operations comprising:
controlling the pre-polarizing magnet to polarize at least the gas phase of the mixed-phase fluid flow to an initial polarization while the first and second electromagnets are unenergized;
controlling the EFNMR detector to measure a plurality of fluid induction decay (FID) values of the polarized gas phase;
determining a velocity of the gas phase based on the plurality of FID values of the polarized gas phase while the first and second electromagnets are unenergized;
energizing the first electromagnet to produce a pulsed magnetic field gradient to suppress one or more signals acquired by the EFNMR detector;
controlling the EFNMR detector simultaneously with the production of the pulsed magnetic field gradient to measure a plurality of FID values of the liquid phase of the mixed-phase fluid;
energizing the second electromagnet to generate a homogeneous polarizing field to polarize the liquid phase of the mixed-phase fluid;
determining a velocity of the liquid phase based on the plurality of FID values of the polarized liquid phase; and
determining a content of the liquid phase based on the plurality of FID values of the mixed-phase fluid.

2. The fluid measurement system of claim 1 , wherein the operation of determining a velocity of the gas phase based on the plurality of FID values of the polarized gas phase comprises applying a pseudo-1D inversion to the plurality of FID values of the gas phase.

3. The fluid measurement system of claim 2 , wherein the operation of determining a velocity of the liquid phase based on the plurality of FID values of the polarized liquid phase comprises applying another pseudo-1D inversion to the plurality of FID values of the liquid phase.

4. The fluid measurement system of claim 3 , wherein the operation of determining a content of the liquid phase based on the plurality of FID values of the mixed-phase fluid comprises determining an oil-water content of the liquid phase with a 2D probability distribution of the velocity of the liquid phase in the mixed-phase fluid flow based on the applied another 1D inversion of the plurality of FID values of the liquid phase and a model kernel matrix.

5. The fluid measurement system of claim 3 , wherein at least one of the pseudo-1D inversion or the another psuedo-1D inversion comprises a Tikhonov inversion.

6. The fluid measurement system of claim 1 , wherein the gas source comprises a pressurized gas source fluidly coupled to the fluid flow circuit between the fluid mixer and the pre-polarizing permanent magnet.

7. The fluid measurement system of claim 1 , wherein the at least two liquids comprise oil and water.

8. The fluid measurement system of claim 1 , wherein the pre-polarizing magnet is positionable at a plurality of distances apart from the EFNMR detector.

9. The fluid measurement system of claim 8 , wherein the operation of controlling the EFNMR detector to measure the plurality of FID values of the polarized gas phase comprises:
controlling the EFNMR detector to measure a first plurality of FID values of the polarized gas phase at a first distance of the plurality of distances; and
controlling the EFNMR detector to measure a second plurality of FID values of the polarized gas phase at a second distance of the plurality of distances.

10. The fluid measurement system of claim 1 , wherein the operation of controlling the EFNMR detector to measure the plurality of FID values of the polarized liquid phase comprises:
controlling the EFNMR detector to measure a first plurality of FID values of the polarized liquid phase at a first pulse time duration of a plurality of electromagnet pulse time durations; and
controlling the EFNMR detector to measure a second plurality of FID values of the polarized liquid phase at a second pulse time duration of the plurality of electromagnet pulse time durations.

11. The fluid measurement system of claim 1 , wherein the plurality of FID values of the polarized gas phase comprise velocity values, and the plurality of FID values of the polarized liquid phase comprise velocity values and T 1 values of the liquid phase.

12. A method for measuring fluid properties, comprising:
circulating a mixed-phase fluid flow through a fluid flow circuit that comprises a gas source, at least two liquid sources, and a fluid mixer that mixes a liquid from each of the at least two liquid sources to form a liquid phase of the mixed-phase fluid flow that includes a gas phase;
circulating the mixed-phase fluid flow through a pre-polarizing magnet;
polarizing at least the gas phase of the mixed-phase fluid flow to an initial polarization with the pre-polarizing magnet;
measuring a plurality of fluid induction decay (FID) values of the polarized gas phase with an Earth's field nuclear magnetic resonance (EFNMR) detector that comprises a radio-frequency (RF) coil, a first electromagnet aligned with the RF coil, and a second electromagnet positioned downstream of and separate from the first electromagnet;
determining a velocity of the gas phase based on the plurality of FID values of the polarized gas phase while the first and second electromagnets are unenergized;
producing a pulsed magnetic field gradient to suppress one or more signals acquired by the EFNMR detector with the first electromagnet;
measuring a plurality of FID values of the liquid phase of the mixed-phase fluid with the EFNMR detector simultaneously with the production of the pulsed magnetic field gradient;
producing a homogeneous polarizing field to polarize the liquid phase of the mixed-phase fluid with the second electromagnet;
determining a velocity of the liquid phase based on the plurality of FID values of the polarized liquid phase; and
determining a content of the liquid phase based on the plurality of FID values of the liquid phase of the mixed-phase fluid.

13. The method of claim 12 , wherein determining a velocity of the gas phase based on the plurality of FID values of the polarized gas phase comprises applying a pseudo-1D inversion to the plurality of FID values of the gas phase.

14. The method of claim 13 , wherein determining a velocity of the liquid phase based on the plurality of FID values of the liquid phase comprises applying another pseudo-1D inversion to the plurality of FID values of the liquid phase.

15. The method of claim 14 , wherein determining a content of the liquid phase based on the plurality of FID values of the mixed-phase fluid comprises determining an oil-water content of the liquid phase with a 2D probability distribution of the velocity of the liquid phase in the mixed-phase fluid flow based on the applied another 1D inversion of the plurality of FID values of the liquid phase and a model kernel matrix.

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Assignees

• Saudi Arabian Oil Co

Inventors

• O'Neill Keelan Thomas
• Johns Michael Leslie
• Fridjonsson Einar Orn
• Stanwix Paul Louis
• Al-Jindan Jana M
• Noui-Mehidi Mohamed Nabil

Classifications

• G01F1/716 Primary

  using electron paramagnetic resonance [EPR] or nuclear magnetic resonance [NMR] · CPC title

• G01R33/445

  MR involving a non-standard magnetic field B0, e.g. of low magnitude as in the earth's magnetic field or in nanoTesla spectroscopy, comprising a polarizing magnetic field for pre-polarisation, B0 with a temporal variation of its magnitude or direction such as field cycling of B0 or rotation of the direction of B0, or spatially inhomogeneous B0 like in fringe-field MR or in stray-field imaging · CPC title

• G01F1/74 Primary

  Devices for measuring flow of a fluid or flow of a fluent solid material in suspension in another fluid · CPC title

• G01R33/307

  specially adapted for moving the sample relative to the MR system, e.g. spinning mechanisms, flow cells or means for positioning the sample inside a spectrometer · CPC title

• G01R33/448

  Relaxometry, i.e. quantification of relaxation times or spin density (G01R33/50 takes precedence) · CPC title