Systems and methods for detecting and measuring oxidizing compounds in test fluids

Abstract

This disclosure relates to improved techniques for detecting and measuring oxidizing compounds in test fluids. Certain embodiments can include a measurement device that can be configured to apply a constant current to the test fluid and measure a reference voltage indicating an electrochemical potential at which electrolysis occurs in the test fluid. The measurement device also can be configured to measure a second voltage indicating an oxidizing potential of the test fluid, and to calculate an oxidizer concentration measurement indicating the concentration of the oxidizing compound in the test fluid based on a voltage difference between the reference voltage and the second voltage.

What is claimed is: 
     
         1 . A system comprising:
 a test fluid comprising a concentration of an oxidizing compound; and   a measurement device configured to:
 apply a constant current to the test fluid; 
 measure a reference voltage indicating an electrochemical potential at which electrolysis occurs in the test fluid; 
 measure a second voltage indicating an oxidizing potential of the test fluid; and 
 calculate an oxidizer concentration measurement indicating the concentration of the oxidizing compound in the test fluid based on a voltage difference between the reference voltage and the second voltage. 
   
     
     
         2 . The system of  claim 1 , wherein:
 the test fluid is water;   the oxidizing compound is ozone;   the reference voltage indicates the electrochemical potential at which water electrolysis occurs in the water; and   the oxidizer concentration measurement is an ozone concentration measurement.   
     
     
         3 . The system of  claim 1 , wherein the measurement device is further configured to calculate a ph measurement in the test fluid. 
     
     
         4 . The system of  claim 1 , wherein the measurement device is further configured to calculate an ion concentration measurement in the test fluid. 
     
     
         5 . The system of  claim 1 , wherein the measurement device comprises:
 a processor;   a power supply that is configured to provide the constant current; and   a first electrode, a second electrode, and a third electrode, wherein:
 the first electrode and the second electrode are included on a circuit to which the constant current is applied when the first electrode and the second electrode are submerged in the test fluid, and the third electrode is not included on the circuit; 
 the first electrode is configured to measure the reference voltage; 
 the third electrode is configured to measure the second voltage; and 
 the first electrode, the second electrode, and the third electrode are each comprised of a noble metal, a passivated transition metal, a glass-like carbon, or some combination thereof. 
   
     
     
         6 . The system of  claim 5 , wherein the measurement device further comprises a fourth electrode that is paired on a second circuit with the third electrode. 
     
     
         7 . The system of  claim 5 , wherein the measurement device is configured to operate in a reverse polarization mode during which the constant current applied to the test fluid is reversed to produce a redox reaction on the first electrode and the second electrode in the test fluid. 
     
     
         8 . The system of  claim 7 , wherein, during operation in the chronopotentiometric mode, the measurement device is configured to take a second oxidizer concentration measurement of the test fluid to evaluate an accuracy of the oxidizer concentration measurement in the test fluid. 
     
     
         9 . The system of  claim 5 , wherein the measurement device further comprises a temperature measurement component that is configured to measure a third voltage indicating a temperature of the test fluid. 
     
     
         10 . The system of  claim 9 , wherein:
 the system further comprises an oxidizer generator that is configured to apply the oxidizing compound to the test fluid;   the processor receives the reference voltage, the second voltage, and the third voltage; and   the processor controls the oxidizer generator based on the reference voltage, the second voltage, and the third voltage.   
     
     
         11 . A method comprising:
 applying a constant current to a test fluid comprising a concentration of an oxidizing compound;   measuring, with a measurement device, a reference voltage indicating an electrochemical potential at which electrolysis occurs in the test fluid;   measuring, with the measurement device, a second voltage indicating an oxidizing potential of the test fluid; and   calculating, with the measurement device, an oxidizer concentration measurement indicating the concentration of the oxidizing compound in the test fluid based on a voltage difference between the reference voltage and the second voltage.   
     
     
         12 . The method of  claim 11 , wherein:
 the test fluid is water;   the oxidizing compound is ozone;   the reference voltage indicates the electrochemical potential at which water electrolysis occurs in the water; and   the oxidizer concentration measurement is an ozone concentration measurement.   
     
     
         13 . The method of  claim 11 , wherein the measurement device is further configured to calculate a ph measurement in the test fluid. 
     
     
         14 . The method of  claim 11 , wherein the measurement device is further configured to calculate an ion concentration measurement in the test fluid. 
     
     
         15 . The method of  claim 11 , wherein the measurement device comprises:
 a processor;   a power supply that is configured to provide the constant current; and   a first electrode, a second electrode, and a third electrode, wherein:
 the first electrode and the second electrode are included on a circuit to which the constant current is applied when the first electrode and the second electrode are submerged in the test fluid, and the third electrode is not included on the circuit; 
 the first electrode is configured to measure the reference voltage; 
 the third electrode is configured to measure the second voltage; and 
 the first electrode, the second electrode, and the third electrode are each comprised of a noble metal, a passivated transition metal, a glass-like carbon, or some combination thereof. 
   
     
     
         16 . The method of  claim 15 , wherein the measurement device further comprises a fourth electrode that is paired on a second circuit with the third electrode. 
     
     
         17 . The method of  claim 15 , wherein the measurement device is configured to operate in a reverse polarization mode during which the constant current applied to the test fluid is reversed to produce a redox reaction on the first electrode and the second electrode in the test fluid. 
     
     
         18 . The method of  claim 17 , wherein, during operation in the chronopotentiometric mode, the measurement device is configured to take a second oxidizer concentration measurement of the test fluid to evaluate an accuracy of the oxidizer concentration measurement in the test fluid. 
     
     
         19 . The method of  claim 15 , wherein the measurement device further comprises:
 measuring a third voltage indicating a temperature of the test fluid using temperature measurement component;   receiving the reference voltage, the second voltage, and the third voltage at the processor; and   controlling an oxidizer generator based on the reference voltage, the second voltage, and the third voltage.   
     
     
         20 . A system comprising:
 a test fluid comprising a concentration of an oxidizing compound; and   a measurement device comprising:
 a processor; 
 a power supply that is configured to provide a constant current; and 
 a first electrode, a second electrode, and a third electrode, wherein:
 the first electrode and the second electrode are included on a circuit to which the constant current is applied when the first electrode and the second electrode are submerged in the test fluid, and the third electrode is not included on the circuit; 
 the first electrode, the second electrode, and the third electrode are each comprised of a noble metal, a passivated transition metal, a glass-like carbon, or some combination thereof; 
 the first electrode is configured to measure a reference voltage indicating an electrochemical potential at which electrolysis occurs in the test fluid; 
 the third electrode is configured to measure a second voltage indicating an oxidizing potential of the test fluid; and 
 the measurement device calculates an oxidizer concentration measurement indicating the concentration of the oxidizing compound in the test fluid based on a voltage difference between the reference voltage and the second voltage. 
 
   
     
     
         21 . A system comprising:
 a test fluid; and   a measurement device configured to:
 apply a constant current to the test fluid; 
 measure a reference voltage indicating an electrochemical potential at which electrolysis occurs in the test fluid; 
 measure a second voltage indicating a potential of the test fluid related to one of an oxidizing potential, a pH potential, or an ion concentration chemical potential; and 
 calculate a concentration measurement in the test fluid based on a voltage difference between the reference voltage and the second voltage.