Opto-Electochemical Sensing System for Monitoring and Controlling Industrial Fluids

• US 20160103089A1
• Filed: 10/14/2014
• Published: 04/14/2016
• Est. Priority Date: 10/14/2014
• Status: Active Grant

• Current Assignee: Chem-Aqua, Inc. (NCH Corporation), Pyxis Lab, Inc.
• Original Assignee: NCH Corporation, Pyxis Lab, Inc.
• Inventors: Boyette, Scott M., Xiao, Caibin, Gu, Jackey, Murray, Jerold
• Granted Patent: US 9,612,221 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G01N 2021/6491 Measuring fluorescence and transmission; Correcting inner filter effect
• CPC Class Codes: G01N 21/51 inside a container, e.g. in an ampoule G01N21/53 takes precedence
• CPC Class Codes: G01N 21/59 Transmissivity G01N21/25 takes precedence
• CPC Class Codes: G01N 21/645 Specially adapted constructive features of fluorimeters
• CPC Class Codes: G01N 2201/0221 Portable; cableless; compact; hand-held
• CPC Class Codes: G01N 2201/062 LED's
• CPC Class Codes: G01N 27/08 which is flowing continuously
• CPC Class Codes: G01N 27/27 Association of two or more measuring systems or cells, each measuring a different parameter, where the measurement results may be either used independently, the systems or cells being physically associated, or combined to produce a value for a further parameter
• CPC Class Codes: G01N 27/4168 Oxidation-reduction potential, e.g. for chlorination of water water analysis G01N33/18

Abstract

A system and method for controlling operating parameters of an industrial fluid system based on measurement of optical and electrochemical properties. The system comprises a handheld or portable meter that can substantially simultaneously measure one or more optical properties and one or more electrochemical properties of a sample of fluid from the fluid system. Information based upon the measurements or calculations made by the system may be used to manually or automatically alter various operating parameters to control the fluid system and aid in maintaining stable operation of the fluid system within preferred specifications.

Claims

1. A portable device for detecting both optical and electrochemical properties of a fluid or fluid mixture, the device comprising:

a sample receptacle for containing a sample of the fluid or fluid mixture;

a light source for directing light to the sample receptacle;

an optical sensor configured to detect an emission or transmission of light through the sample receptacle or from a compound in the sample;

at least two electrodes, a portion of each disposed to contact the sample in the sample receptacle; and

an electronic module configured to receive signals from the optical sensor and electrodes and to calculate a first property based on the signal from the optical sensor and a second property based on a signal from the electrodes.

2. The device of claim 1 wherein the first property is a concentration of a chemical in the sample, a concentration of the compound, fluorescence, transmission, absorbance, turbidity, color, optical density, light scattering, or clarity of the sample;

and

wherein the second property is concentration of the chemical in the sample, conductivity, cyclic voltammetry to determine oxidation and reduction potentials, or open circuit potential of the sample.

3. The device of claim 2 further comprising a second light source and a second optical sensor and wherein the electronic module is configured to receive a signal from the second optical sensor and to calculate a third property based on the signal from the second optical sensor.

4. The device of claim 3 wherein the third property is a concentration of a chemical in the sample, a concentration of the compound, fluorescence, transmission, absorbance, turbidity, color, optical density, light scattering, or clarity of the sample, and wherein the first and third properties are different from each other.

5. The device of claim 3 wherein the electronic module is configured to calculate a fourth property based on another signal from the first optical sensor and to calculate a fifth property based on another signal from the second optical sensor.

6. The device of claim 5 wherein the fourth and fifth properties are a concentration of a chemical in the sample, a concentration of the compound, fluorescence, transmission, absorbance, turbidity, color, optical density, light scattering, or clarity of the sample.

7. The device of claim 6 wherein the first property is fluorescence and wherein one or more of the third, fourth or fifth properties is absorbance, color, or turbidity and wherein the electronic module corrects the calculated fluorescence based on one or more of the calculated third, fourth or fifth properties.

8. The device of claim 1 further comprising a second light source and a second optical detector;

wherein the first and second light sources and first and second optical detectors are disposed around the receptacle such that the first light source is disposed substantially opposite the first optical detector and substantially at a right angle from the second optical detector and the second light source is disposed substantially opposite the second optical detector and substantially at a right angle from the first optical detector;

wherein the first optical detector is configured to send a first signal to the electronic module based on light from the first light source and to send a second signal to the electronic module based on light from the second light source;

wherein the second optical detector is configured to send a third signal to the electronic module based on light from the second light source and to send a fourth signal to the electronic module based on light from the first light source;

wherein the first property is calculated based on the first signal;

wherein the electronic module is configured to calculate a third property based on the second signal, a fourth property based on the third signal, and a fifth property based on the fourth signal.

9. The device claim 8 wherein the third property is fluorescence;

wherein one or more of the first, fourth, and fifth properties are absorbance, color, or turbidity; and

wherein the electronic module corrects the calculated fluorescence based on one or more of the first, fourth, or fifth properties.

10. The device of claim 1 further comprising a temperature sensor for measuring a temperature of the sample.

11. The device of claim 1 further comprising a power source.

12. The device of claim 11 wherein the power source is a battery or solar cells.

13. The device of claim 1 further comprising a connection between the electronic module and an external power source.

14. The device of claim 13 where the power source comprises a peripheral computer or communication device having an independent source of power or a direct connection to an alternating or direct current.

15. The device of claim 1 further comprising a display for displaying results of the calculated properties.

16. The device of claim 1 wherein the electronic module comprises memory for storing results of the calculated properties.

17. The device of claim 1 further comprising a receptacle configured to receive a removable memory chip for storing results of the calculated properties measured, wherein the receptacle allows data to be transferred from the electronic module to the removable memory chip.

18. The device of claim 1 wherein the sample receptacle comprises a sample cell having an internal volume between 1 to 20 ml.

19. The device of claim 1 further comprising a housing for containing the light source, optical sensor, electronic module, electrodes, and sample receptacle, wherein the housing has a length dimension less than about 10 inches and a width dimension less than about 5 inches.

20. The device of claim 1 wherein a portion of each electrode is disposed through a wall of the sample receptacle to allow contact with the sample.

21. The device of claim 1 wherein a portion of the first electrode is disposed as an external coating on the light source and a portion of the second electrode is disposed as an external coating on the optical sensor, wherein the external coatings are in contact with the sample.

31. The method of claim 20 further comprising calculating a third property of the sample based on the first signal, the second signal or both signals.

22. A method of determining properties of a fluid or fluid mixture, the method comprising:

placing a sample of the fluid or fluid mixture in a sample cell;

directing light from a light source to the sample cell;

detecting an emission or transmission of light through the sample cell or from a compound in the sample with an optical sensor;

measuring a change of electric potential between two of at least two electrodes in contact with the sample in the sample cell;

calculating a first property of the fluid based on the detected emission or transmission;

calculating a second property of the fluid based on measured change of electric potential; and

wherein the calculating steps are performed by an electronic module connected to the optical sensor and electrodes.

23. The method of claim 22 further comprising providing a single apparatus housing the sample cell, light source, optical sensor, electrodes, and electronic module.

24. The method of claim 23 further comprising displaying results of the calculating steps on a display screen on the apparatus and wherein the first and second properties may be the same property or different properties.

25. A method of controlling a fluid system, the method comprising:

placing a sample of fluid from the fluid system in a sample cell;

detecting a first signal representing at least one optical property of the sample;

detecting a second signal representing at least one electrochemical property of the sample;

calculating a first property of the sample based on the first signal;

calculating a second property of the sample based on the second signal;

disposing of the sample;

altering at least one operational parameter of the fluid system if one or more of the properties of the sample is out of a first range of values or above or below a first pre-set value specified for that property;

periodically repeating the previous steps with a new sample of fluid from the fluid system; and

wherein said detecting steps are performed substantially simultaneously using a portable meter and a single sample.

26. The method of claim 25 wherein the first property is fluorescence, transmission, absorbance, turbidity, color, optical density, light scattering, or concentration of a chemical;

and

wherein the second property is conductivity, cyclic voltammetry to determine oxidation and reduction potentials, open circuit potential, or concentration of a chemical.

29. The method of claim 25 further comprising the step of generating an alarm signal if one or more of the properties of the sample is out of a first range of values or above or below a pre-set value specified for that property.

30. The method of claim 26 wherein the operational parameter being altered is an amount of chemical treatment product added to the fluid system, a rate of blowdown, or a rate of fluid addition to the fluid system.

32. The method of claim 25 further comprising:

detecting a third signal representing at least one optical property of the sample;

calculating a third property of the sample based on the third signal; and

wherein the optical property represented by the first signal is different from the optical property represented by the third signal.

33. The method of claim 25 where the fluid system being controlled is a closed or open configuration cooling system, hot water system, or boiler system.

34. The method of claim 25 further comprising communicating data or commands from the portable device to a remote control system configured to provide control of the fluid system by sending signals to one or more components in the fluid system to automatically alter at least one of the operational parameters if one or more of the properties of the sample is out of a first range of values or above or below a pre-set value specified for that property.

35. The method of claim 34 wherein the remote control system is configured for feed-forward or feedback control.

36. The method of claim 34 wherein the remote control system is configured for open or closed loop control.

37. The method of claim 25 further comprising displaying data on the calculated properties on a display screen on the portable meter.

38. The method of claim 25 wherein the step of altering one or more parameters of operation comprises manually adjusting one or more components in the fluid system or manually inputting instructions into an electronic control system to adjust one or more components in the fluid system.

39. The method of claim 29 wherein the alarm signal is an audible signal, a visual signal, or both and is generated by the portable meter.

40. The method of claim 39 further comprising generating a second alarm signal when one or more of the properties calculated is within a second or third range of values specified for that property or above or below a second or third pre-set value specified for that property, and wherein the second alarm signal is distinguishable from the first alarm signal.

41. The method of claim 25 further comprising:

detecting one or more of a third, fourth, or fifth signal representing a second, third, or fourth optical property;

wherein the first property is fluorescence and one or more of the second, third, or fourth optical properties is absorbance, color, or turbidity; and

correcting the calculated fluorescence based on one or more of the second, third, or fourth optical properties prior to the altering step.

27. The method of 26 wherein the first property is a first value of a concentration of a chemical and the second property is a second value of a concentration of the same chemical.

28. The method of claim 27 further comprising comparing the first value and the second value to determine a difference in the values;

and

wherein the operational parameter is an amount of treatment product added to the fluid system and the amount is altered if the difference in the values is greater than a pre-set value.