Method and system for determining flow distribution through a component

Patent metadata

Field	Value
Publication number	US-9746434-B2
Application number	US-201414226997-A
Country	US
Kind code	B2
Filing date	Mar 27, 2014
Priority date	Mar 28, 2013
Publication date	Aug 29, 2017
Grant date	Aug 29, 2017

Abstract

Systems and methods for determining the flow distribution of a fluid through a component with a sensing cable including an optical fiber sensor array aligned with a heating element disposed in the component. An excitation source is configured to propagate at least one heat pulse through the heating element along at least a portion of the sensing cable to affect an exchange of thermal energy between the heating element and the fluid exposed to the sensing cable. An optical signal is adapted to receive a signal from each of a plurality of sensor locations and measure a temperature profile corresponding to the heat pulse at the sensor locations. A control unit is configured to determine a flow of the fluid by determining one or more properties of the fluid exposed to the sensing cable at each of the plurality of sensor locations based on the temperature profile corresponding thereto. The present invention can be effective in accurate and high spatial resolution of flow distributions through vessel components, such as a particulate bed (such as a reactor catalyst bed), a wash bed including packing material, an absorbent bed, a structured bed, a filter, or the like.

First claim

What is claimed is:

1. A method for determining the flow distribution of a fluid through a component, comprising:
providing within a component a sensing cable including an optical fiber sensor array aligned with a heating element;
propagating at least one heat pulse through the heating element along at least a portion of the sensing cable to affect an exchange of thermal energy between the heating element and the fluid exposed to the sensing cable;
measuring, over time, a temperature profile of the sensing cable corresponding to the heat pulse at each of a plurality of sensor locations on the optical fiber sensor array; and
determining a flow of the fluid by determining one or more properties of the fluid exposed to the sensing cable at each of the plurality of sensor locations based on the temperature profile corresponding thereto,
wherein the component is a hydroprocessing reactor which includes a particulate bed and the particulate bed is comprised of catalyst particles.

2. The method of claim 1 , wherein the catalyst particles are comprised of a hydrodesulfurization catalyst, a hydrodenitrogenation catalyst, a hydrodeoxygenation catalyst, a hydrocracking catalyst, a hydroreforming catalyst, a hydroisomerization catalyst, or any combination thereof.

3. The method of claim 1 , wherein measuring, over time, the temperature profile includes measuring using fiber Bragg grating array based sensing, Raman scattering based sensing, Rayleigh scattering based sensing, or Brillioun scattering based sensing.

4. The method of claim 1 , wherein the heating element includes a resistive heating element and wherein propagating the at least one heat pulse includes applying an electrical pulse with a predetermined frequency and predetermined waveform.

5. The method of claim 1 , wherein propagating at least one heat pulse through the heating element includes propagating the at least one heat pulse through a heating element aligned adjacent to the optical fiber sensor array.

6. The method of claim 1 , wherein propagating at least one heat pulse through the heating element includes propagating the at least one heat pulse through a heating element disposed concentrically with the optical fiber sensor array.

7. The method of claim 1 , wherein the heating element includes a thermoelectric device and wherein propagating at least one heat pulse through the heating element includes propagating a cooling pulse.

8. The method of claim 1 , further comprising coating the sensing cable with an anti-fouling coating to prevent formation of deposits thereon.

9. The method of claim 1 , wherein the sensing cable further includes an outer diameter including a metal and mineral insulation material.

10. The method of claim 1 , wherein measuring the temperature profile corresponding to the heat pulse at each of the plurality of sensor locations includes, for each sensor location, measuring at least a heating temperature measurement during propagation of the heat pulse over the sensor location, a peak temperature measurement, and a cooling temperature measurement after propagation of the heat pulse over the sensor.

11. The method of claim 1 , wherein measuring the temperature profile corresponding to the heat pulse at each of the plurality of sensor locations includes, for each sensor location, measuring a plurality of temperatures over a period of time upon arrival of the heat pulse at the sensor location.

12. The method of claim 11 , wherein determining the flow of the fluid includes, for each temperature profile, performing a regression of the plurality of temperatures over a logarithm of corresponding measurement times for a predetermined time window in the period of time to generate a slope and an intercept of the regression, wherein the slope and the intercept relate to the flow of the fluid over the sensing cable at the sensor location.

13. The method of claim 12 , wherein the predetermined time window includes a time window during a heating stage, the heating stage corresponding to a period of time during propagation of the heat pulse over the sensor location or a time window during a cooling stage, the cooling stage corresponding to a period of time after propagation of the heat pulse over the sensor.

14. The method of claim 11 , wherein determining the flow of the fluid includes, for each temperature profile:
generating a time derivative by calculating a derivative of the plurality of temperature measurements with respect to time; applying a transform to the time derivative to generate a complex spectrum; and
determining an amplitude and a phase of the complex spectrum, wherein the amplitude and the phase of the complex spectrum relate to the flow of the fluid over the sensing cable at the sensor location.

15. The method of claim 14 , wherein determining the flow of the fluid further includes, for each temperature profile:
generating a frequency derivative spectrum by calculating the derivative of the complex spectrum with respect to frequency; and
determining an amplitude and a phase of the frequency derivative spectrum, wherein the amplitude and the phase of the frequency derivative spectrum relate to the flow of the fluid over the sensing cable at the sensor location.

16. The method of claim 1 , wherein determining the flow of the fluid further includes detecting a misdistribution condition in the component by monitoring the temperature profile corresponding to each of the plurality of sensor locations, and comparing the monitored temperature profiles to predetermined temperature profiles corresponding to a desired operation condition.

17. The method of claim 1 , wherein determining the flow of the fluid further includes detecting a misdistribution condition in the component by monitoring a first temperature profile corresponding to each of the plurality of sensor locations and at least a second temperature profile corresponding to each of the plurality of sensor locations, and comparing the first and second temperature profiles to detect a change in operation condition.

18. The method of claim 1 , wherein the sensing cable is disposed in a grid configuration within the component, the method further comprising generating a multi-dimensional flow distribution based on the temperature profile corresponding to each sensor location.

19. A system for determining the flow distribution of a fluid through a component, comprising:
a sensing cable including an optical fiber sensor array aligned with a heating element disposed in the component, the optical fiber sensor array having a plurality of sensor locations;
an excitation source coupled with the heating element and configured to propagate at least one heat pulse through the heating element along at least a portion of the sensing cable to affect an exchange of thermal energy between the heating element and the fluid exposed to the sensing cable;
an optical signal interrogator coupled with the optical fiber sensor array and adapted to receive a signal from each of the plurality of sensor locations and configured to measure, over time, a temperature profile of the sensing cable corresponding to the heat pulse at each of the plurality of sensor locations on the optical fiber sensor array; and
a control unit, coupled with the heating element and the optical signal interrogator, to determine a flow of the fluid by determining one or more properties of the fluid exposed to the sensing cable at each of the plurality of sensor locations based on the temperature profile corresponding thereto,
wherein the component is a hydrop

Assignees

• Zhang Yibing
• Song Limin
• Keiser Geoff
• Hergenrother Michael L
• Stober Berne K
• Kalamaras Patricia H
• Umansky Benjamin S
• Exxonmobil Res & Eng Co

Inventors

• Zhang Yibing
• Song Limin
• Keiser Geoff
• Hergenrother Michael L
• Stober Berne K
• Kalamaras Patricia H
• Umansky Benjamin S

Classifications

• G01N25/18 Primary

  by investigating thermal conductivity (by calorimetry G01N25/20; by measuring change of resistance of an electrically-heated body G01N27/18) · CPC title

• G01F1/74

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

• G01F1/661

  using light · CPC title

• G01N25/00

  Investigating or analyzing materials by the use of thermal means (G01N3/00 - G01N23/00 take precedence) · CPC title

• G01F1/684

  Structural arrangements; Mounting of elements, e.g. in relation to fluid flow · CPC title