Method and apparatus for determining GVF—gas volume fraction—for aerated fluids and liquids in flotation tanks, columns, drums, tubes, vats

Patent metadata

Field	Value
Publication number	US-11035826-B1
Application number	US-202117144333-A
Country	US
Kind code	B1
Filing date	Jan 8, 2021
Priority date	Mar 9, 2010
Publication date	Jun 15, 2021
Grant date	Jun 15, 2021

Abstract

The invention provides a signal processor that receives a signal containing information about an acoustic signal that is generated by at least one acoustic transmitter, that travels through an aerated fluid in a container, and that is received by at least one acoustic receiver arranged in relation to the container, including inside the container; and determines the gas volume fraction of the aerated fluid based at least partly on the speed of sound measurement of the acoustic signal that travels through the aerated fluid in the container. The signal processor also sends an output signal containing information about the gas volume fraction of the aerated fluid. The signal processor may be configured together with at least one acoustic transmitter, the at least one acoustic receiver, or both.

First claim

What is claimed is:

1. Apparatus comprising:
a container ( 40 ) having an aerated fluid therein;
an array of acoustic transmitters ( 44 ) that is arranged in relation to the container having aerated fluid therein being processed and configured to generate acoustic signals that travel through the aerated fluid;
an array of acoustic receivers ( 46 ) that is arranged in the container and configured to receive the acoustic signals and provide a signal containing information about the acoustic signals generated by the array of acoustic transmitters, the array of acoustic receivers and the array of acoustic transmitters being separated by a known distance;
a signal processor ( 26 ) configured to:
receive the signal;
determine the gas volume fraction of the aerated fluid based at least partly on upon a speed of sound measurement of the acoustic signals that travel through the aerated fluid in the container, the signal processor being configured to determine the speed of sound measurement based at least partly on an elapsed or propagation time between generation and detection of the acoustic signals and the known distance between the array of acoustic transmitters and the array of acoustic receivers, wherein the signal processor is configured to receive signals containing information about the acoustic signals that are generated by the array of acoustic transmitters, that travel through the aerated fluid in the container, having each acoustic transmitter selectively encoded with a different frequency, slice of spectrum, chirp/modulation characteristic allowing each channel to be individually analyzed, that travel through the aerated fluid in the container, and that are received by the array of acoustic receivers; and
provide an output signal containing information about the gas volume fraction of the aerated fluid to control the entrained air in the aerated fluid being processed in the container, based upon the signal received, including for providing a chemical additive to the aerated fluid being processed in the container.

2. Apparatus according to claim 1 , wherein the speed of sound measurement is based at least partly on at least one of the acoustic transmitters ( 44 ) and the acoustic receiver probes ( 46 ) being arranged at the same height in relation to the container ( 40 ).

3. Apparatus according to claim 1 , wherein the speed of sound measurement is based at least partly on the acoustic transmitters ( 44 ) emitting the acoustic signals at a frequency in a proper frequency range so that entrained air modifies the speed of sound in the aerated fluid.

4. Apparatus according to claim 1 , wherein the receivers ( 46 ) comprise two acoustic receivers arranged inside the container ( 40 ).

5. Apparatus according to claim 1 , wherein the signal processor ( 26 ) is configured to provide the output signal for providing the chemical additive to the aerated fluid being processed in the container ( 40 ) which is a flotation tank in a flotation process.

6. Apparatus according to claim 1 , wherein the apparatus comprises a concrete mixer ( 162 ) having the acoustic transmitters ( 44 ) and the acoustic receivers ( 46 ), and the aerated fluid comprised in the container ( 40 ) is part of a mixing process for making concrete which includes mixing concrete in a ready mix truck ( 140 ) or in a stationary concrete mixer box.

7. Apparatus according to claim 1 , wherein the apparatus comprises a food processor having the acoustic transmitters ( 44 ) and the acoustic receivers ( 46 ), and the aerated fluid comprised in the container ( 40 ) is part of a food process which includes adding lysene for producing ice cream.

8. Apparatus according to claim 1 , wherein the acoustic transmitters ( 44 ) are configured to generate acoustic signals by driving a piezoelectric material or a mechanical impulse.

9. Apparatus according to claim 1 , wherein the acoustic transmitters ( 44 ) are arranged on the outside of the container ( 40 ).

10. Apparatus according to claim 1 , wherein the acoustic transmitters ( 44 ) are arranged on the inside of the container ( 40 ).

11. Apparatus according to claim 1 , wherein the apparatus comprises at least one of the acoustic transmitters ( 44 ) that is omnidirectional.

12. Apparatus according to claim 1 , wherein the apparatus comprises the container ( 40 ) that is a flotation column or tank.

13. Apparatus according to claim 1 , wherein the apparatus comprises a chemical additive device configured to receive the output signal, and also configured to add the chemical additive to the container ( 40 ) in order to control the entrained air in the aerated fluid in a closed loop system.

14. Apparatus according to claim 1 , wherein the apparatus comprises a ready mix truck ( 140 ) and a drum inspection hatch ( 150 ) of the ready mix truck and at least one of the acoustic transmitters ( 44 ) and at least one of the acoustic receivers ( 46 ) take the form of a projector/receiver pair separated by a small distance and attached to the drum inspection hatch ( 150 ), wherein the projector/receiver pair is installed through the drum inspection hatch ( 150 ) so as to be inside the cavity of a mixer drum of the ready mix truck ( 140 ), or wherein the apparatus comprises a drum inspection hatch ( 150 ) which is configured to form a cavity and at least one of the acoustic transmitters ( 44 ) and at least one of the acoustic receivers ( 46 ) take the form of a projector/receiver pair separated by a small distance and attached to the drum inspection hatch ( 150 ) and the projector/receiver pair is installed in the cavity and exposed to the concrete inside the container ( 40 ) which is a mixer drum ( 142 ), or wherein the apparatus comprises a ready mix truck ( 140 ) and a drum inspection hatch ( 150 ) of the ready mix truck and at least one of the acoustic transmitters ( 44 ) and at least one of the acoustic receivers ( 46 ) take the form of a projector/receiver pair separated by a small distance and attached to the drum inspection hatch ( 150 ) and the apparatus comprises a wireless transmitter configured to provide a wireless signal containing information about an air content value of concrete in the container ( 40 ) to a local display and/or communications module on the ready mix truck ( 140 ).

15. Apparatus according to claim 14 , wherein the gas volume fraction of the aerated fluid is based at least partly on multipath interrogation of each measurement point, where each acoustic receiver ( 46 ) is configured to detect a respective acoustic signal from each acoustic transmitter ( 44 ).

16. Apparatus according to claim 1 , wherein the gas volume fraction of the aerated fluid determined is based at least partly on multipath interrogation of each measurement point, where each acoustic receiver is configured to detect a respective acoustic signal from each acoustic transmitter.

17. Apparatus according to claim 1 , wherein the apparatus comprises at least one of the acoustic transmitters ( 44 ) that is arranged on the outside of the container ( 40 ) and operates through a wall of the container, wherein the apparatus comprises at least one of the acoustic transmitters ( 44 ) that is inserted in a port in a wall that allows contact with the aerated fluid, and wherein the apparatus comprises a diaphragm and at least one of the acoustic transmitters ( 44 ) that is configured to generate low frequency acoustics by driving the diaphragm, including by pressure or mechanical/electrical excitation, used to propagate a sound signal into the aerated fluid.

18. A method for determining a gas volume fract

Assignees

• Cidra Corporate Services Inc

Inventors

• Fernald Mark R
• Bailey Timothy J
• Loose Douglas H
• Sullivan James M
• Biesak John
• Kersey Alan D
• Davis Michael A

Classifications

• G01F1/7082

  using acoustic detecting arrangements · CPC title

• G01N29/02 Primary

  Analysing fluids (using acoustic emission techniques G01N29/14 {; constructional or flow details for analysing fluids G01N29/222; optoacoustic fluid cells G01N29/2425}) · 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

• G01N29/343 Primary

  pulse waves, e.g. particular sequence of pulses, bursts · CPC title

• G01N29/262

  by electronic orientation or focusing, e.g. with phased arrays (phased arrays per se G10K11/34) · CPC title