JP2006242778A - Oxidation-reduction potential measuring device and measuring method of oxidation-reduction potential - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To measure stably an oxidation-reduction potential of liquid to be measured. <P>SOLUTION: This oxidation-reduction potential measuring device 100 has a measuring vessel 101 for storing reduction water 115 which is a measuring object of the oxidation-reduction potential; a working electrode 105 and a reference electrode 107 arranged in contact with the reduction water 115 in the measuring vessel 101, for measuring the oxidation-reduction potential of the reduction water 115; a communication port of a liquid supply tube 109 provided near the bottom part of the measuring vessel 101, for supplying the reduction water 115 to the measuring vessel 101; and a communication port of a drain tube 111 provided near the bottom part of the measuring vessel 101, for discharging the reduction water 115 from the measuring vessel 101. A communication port of an overflow tube 113 for overflowing and discharging excessive reduction water 115 in the measuring vessel 101 is provided on a furthermore upper part of the communication port of the liquid supply tube 109. The working electrode 105 and the reference electrode 107 are arranged on the furthermore lower side than the communication port of the overflow tube 113. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a redox potential measuring apparatus and a redox potential measuring method.

  Reduced water (hydrogen water), which is one of functional waters, is used for CMP of a Cu wiring, CMP cleaning, peeling rinsing and the like in a semiconductor device manufacturing line, for example. In fields other than semiconductors, for example, they are widely used for cleaning liquid crystals and industrial parts.

  In order to control the water quality of the reduced water, the pH and oxidation reduction potential (ORP) are monitored. However, hydrogen gas may adhere to the surface of the ORP electrode (platinum), making correct measurement difficult.

  Conventionally, as a technique for preventing bubble contact with the ORP electrode, there is one disclosed in Patent Document 1. In Patent Document 1, a measurement tank having a double structure including an outer cylinder and an inner cylinder is used, the inner cylinder is used as a collision plate, a liquid supply pipe is provided at the bottom of the measurement tank, and a liquid discharge pipe is provided at the upper part of the measurement tank. A redox potential measuring device is described.

This apparatus is configured such that the liquid discharge pipe is positioned above the liquid supply pipe and the oxidation-reduction potential measurement electrode, and the liquid always flows out due to overflow. Thereby, it is said that a new liquid always contacts an electrode by an upward flow, and the fluctuation | variation of a measured value can be prevented.
JP 2004-340717 A

  However, when the inventor examined the technique described in Patent Document 1, there was room for improvement in that the measurement of the oxidation-reduction potential was stably performed over a long period of time with a simple apparatus configuration.

According to the present invention,
A measuring tank for storing a liquid to be measured whose oxidation-reduction potential is to be measured;
An electrode that is disposed so as to be in contact with the liquid to be measured in the measurement tank, and that measures a redox potential of the liquid to be measured;
A supply port that is provided near the bottom of the measurement tank and supplies the liquid to be measured to the measurement tank;
Provided near the bottom of the measurement tank, and a discharge port for discharging the liquid to be measured from the measurement tank;
There is provided an oxidation-reduction potential measuring device characterized by comprising:

Moreover, according to the present invention,
Contacting an electrode for measuring the oxidation-reduction potential of the measurement liquid with the measurement liquid, and measuring the oxidation-reduction potential of the measurement liquid;
After the step of measuring the oxidation-reduction potential, discharging the liquid to be measured from the vicinity of the bottom of the measurement tank and exposing the surface of the electrode;
After the step of exposing the surface of the electrode, supplying a liquid to be measured from the vicinity of the bottom of the measurement tank, and bringing the electrode into contact with the liquid to be measured again;
A method for measuring an oxidation-reduction potential is provided.

  According to the present invention, since the discharge port for discharging the liquid to be measured is provided in the vicinity of the bottom of the measurement tank, the liquid to be measured can be discharged from the discharge port to expose the electrode. For this reason, bubbles attached to the electrode during contact with the liquid to be measured can be removed, and then the electrode is brought into contact with the liquid to be measured again to measure the oxidation-reduction potential. Therefore, by using this measuring apparatus, it is possible to stably measure the redox potential.

  In the present invention, the fact that the discharge port is provided in the vicinity of the measurement tank means that the discharge port is disposed at a position sufficiently low so that the electrode can be exposed when the liquid to be measured is discharged, For example, the supply port can be provided at a low position on the bottom surface or side surface of the measurement tank.

  In the present invention, since the supply port is provided in the vicinity of the bottom of the measurement tank, the measurement liquid is prevented from entraining bubbles in the measurement tank when the measurement liquid is supplied into the measurement tank. it can. For this reason, the fluctuation | variation of the oxidation reduction potential by mixing of the gas to a to-be-measured liquid can be suppressed.

  In the present invention, the measurement tank containing the measurement liquid means that the measurement tank is filled with an amount of the measurement liquid in such an amount that the electrode for measuring the oxidation-reduction potential is in contact with the measurement liquid. It is not limited to the case where the liquid stays in the measurement tank, and the measurement tank is arranged in the flow path of the measurement liquid, and the measurement liquid is continuously supplied to and discharged from the measurement liquid. May be. Further, the supply port and the discharge port are configured such that the measurement tank is filled with an amount of the liquid to be measured such that the electrode is in contact with the measurement liquid.

  In addition, the supply port is provided in the vicinity of the measurement tank is a position where the gas mixture into the measurement liquid can be sufficiently suppressed, and the measurement liquid is gently supplied from the lower part to the upper part of the measurement tank. For example, the supply port can be provided at a low position on the bottom surface or side surface of the measurement tank.

According to the present invention,
A measuring tank for storing a liquid to be measured whose oxidation-reduction potential is to be measured;
An electrode that is disposed so as to be in contact with the liquid to be measured in the measurement tank, and that measures a redox potential of the liquid to be measured;
A supply port that is provided near the bottom of the measurement tank and supplies the liquid to be measured to the measurement tank;
An excess liquid discharge port provided in the measurement tank, for discharging excess liquid to be measured in the measurement tank,
Vibration means for applying vibration to the liquid to be measured in the measurement tank;
Have
There is provided an oxidation-reduction potential measuring apparatus, wherein the electrode is disposed below the surplus liquid discharge port.

Moreover, according to the present invention,
An oxidation reduction characterized by measuring an oxidation-reduction potential of the measurement liquid while vibrating the measurement liquid while an electrode for measuring the oxidation-reduction potential of the measurement liquid is in contact with the measurement liquid. A method for measuring potential is provided.

  According to the present invention, when measuring the oxidation-reduction potential of a liquid to be measured, vibration can be given to the liquid to be measured. Giving vibration to the liquid to be measured refers to giving vibration to the liquid to be measured such that turbulent flow is generated in the vicinity of the electrode. By doing so, bubbles attached to the electrode surface can be effectively removed. Therefore, it is possible to stably measure the redox potential of the liquid to be measured.

According to the present invention,
A measuring tank for storing a liquid to be measured whose oxidation-reduction potential is to be measured;
An electrode that is disposed so as to be in contact with the liquid to be measured in the measurement tank, and that measures a redox potential of the liquid to be measured;
A supply port that is provided near the bottom of the measurement tank and supplies the liquid to be measured to the measurement tank;
An excess liquid discharge port provided in the measurement tank, for discharging excess liquid to be measured in the measurement tank,
Stirring means for stirring the liquid to be measured in the measurement tank;
Have
There is provided an oxidation-reduction potential measuring apparatus, wherein the electrode is disposed below the surplus liquid discharge port.

Moreover, according to the present invention,
An oxidation reduction characterized by measuring an oxidation-reduction potential of the measurement liquid while stirring the measurement liquid in a state where an electrode for measuring the oxidation-reduction potential of the measurement liquid is in contact with the measurement liquid. A method for measuring potential is provided.

  According to the present invention, when measuring the oxidation-reduction potential of the liquid to be measured, the liquid to be measured can be stirred. Stirring the liquid to be measured refers to stirring the liquid to be measured so that a turbulent flow is generated in the vicinity of the electrode. By doing so, bubbles attached to the electrode surface can be effectively removed. Therefore, it is possible to stably measure the redox potential of the liquid to be measured.

According to the present invention,
A measuring tank for storing a liquid to be measured whose oxidation-reduction potential is to be measured;
An electrode that is disposed so as to be in contact with the liquid to be measured in the measurement tank, and that measures a redox potential of the liquid to be measured;
A supply port that is provided near the bottom of the measurement tank and supplies the liquid to be measured to the measurement tank;
An excess liquid discharge port provided in the measurement tank, for discharging excess liquid to be measured in the measurement tank,
In the vicinity of the electrode arranged in the measurement tank, a gas supply unit for introducing an inert gas,
Have
There is provided an oxidation-reduction potential measuring apparatus, wherein the electrode is disposed below the surplus liquid discharge port.

Moreover, according to the present invention,
Oxidation characterized in that an electrode for measuring a redox potential of a liquid to be measured is brought into contact with the liquid to be measured and an oxidation-reduction potential of the liquid to be measured is measured while introducing an inert gas in the vicinity of the electrode. A method for measuring the reduction potential is provided.

  According to the present invention, the oxidation-reduction potential of the liquid to be measured can be measured while introducing an inert gas in the vicinity of the electrode. For this reason, even when measurement is continued for a long period of time, bubbles adhering to the electrode surface can be removed as the inert gas rises. Therefore, it is possible to stably measure the redox potential of the liquid to be measured.

  In the present invention, the gas supply unit may be any member that supplies an inert gas and generates an air flow that can remove bubbles in the vicinity of the electrode. For example, the gas supply unit may be an inert gas outlet. Can do. In the present invention, the inert gas refers to a gas that does not affect the oxidation-reduction potential measurement.

According to the present invention,
A measuring tank for storing a liquid to be measured whose oxidation-reduction potential is to be measured;
An electrode that is disposed so as to be in contact with the liquid to be measured in the measurement tank, and that measures a redox potential of the liquid to be measured;
A supply port that is provided near the bottom of the measurement tank and supplies the liquid to be measured to the measurement tank;
An excess liquid discharge port provided in the measurement tank, for discharging excess liquid to be measured in the measurement tank,
A liquid feeding section for feeding the liquid to be measured from the supply port into the measurement tank so that the inside of the measurement tank has a positive pressure with respect to the outside;
Have
The electrode is disposed below the excess liquid discharge port;
An oxidation-reduction potential measuring device is provided in which the measurement tank has a sealed structure.

Moreover, according to the present invention,
The electrode for measuring the oxidation-reduction potential of the liquid to be measured is in contact with the liquid to be measured in a sealed measuring tank, and the inside of the measuring tank is set to a positive pressure from the outside of the measuring tank. There is provided a method for measuring a redox potential characterized by measuring a redox potential of a liquid.

  According to the present invention, the redox potential can be measured by bringing the measured liquid into contact with the electrode in a state where the measured liquid is at a positive pressure from the outside. For this reason, since generation | occurrence | production of the bubble in a measurement tank can be suppressed, a redox potential measurement can be performed stably for a long period of time.

According to the present invention,
A measuring tank for storing a liquid to be measured whose oxidation-reduction potential is to be measured;
An electrode that is disposed so as to be in contact with the liquid to be measured in the measurement tank, and that measures a redox potential of the liquid to be measured;
A supply port that is provided near the bottom of the measurement tank and supplies the liquid to be measured to the measurement tank;
An excess liquid discharge port provided in the measurement tank, for discharging excess liquid to be measured in the measurement tank,
A cooling means for cooling the liquid to be measured;
Have
There is provided an oxidation-reduction potential measuring apparatus, wherein the electrode is disposed below the surplus liquid discharge port.

Moreover, according to the present invention,
An oxidation-reduction potential characterized by measuring an oxidation-reduction potential of the measurement liquid by bringing an electrode for measuring the oxidation-reduction potential of the measurement liquid in contact with the measurement liquid while the measurement liquid is cooled. A measurement method is provided.

  According to the present invention, the redox potential can be measured by bringing the liquid to be measured into contact with the electrode in a cooled state. For this reason, since generation | occurrence | production of the bubble in a measurement tank can be suppressed, a redox potential measurement can be performed stably for a long period of time.

  In the present invention, to cool the liquid to be measured refers to lowering the temperature of the liquid to be measured to a temperature that can suppress the generation of bubbles in the liquid to be measured. It means cooling.

According to the present invention,
A measuring tank for storing a liquid to be measured whose oxidation-reduction potential is to be measured;
An electrode that is disposed so as to be in contact with the liquid to be measured in the measurement tank, and that measures a redox potential of the liquid to be measured;
A cleaning tank containing a cleaning solution for cleaning the electrode;
Have
The measuring tank is
A supply port that is provided near the bottom of the measurement tank and supplies the liquid to be measured to the measurement tank;
A discharge port for discharging the liquid to be measured from the measurement tank;
A first electrode mounting portion for mounting the electrode in the measuring tank;
Have
The washing tank is
There is provided an oxidation-reduction potential measuring device having a second electrode mounting portion for mounting the electrode in the cleaning tank.

Moreover, according to the present invention,
Contacting an electrode for measuring the oxidation-reduction potential of the measurement liquid with the measurement liquid, and measuring the oxidation-reduction potential of the measurement liquid;
After the step of measuring the oxidation-reduction potential, the step of cleaning the electrode in contact with a cleaning solution;
After the step of bringing the electrode into contact with the cleaning liquid and cleaning, the step of bringing the electrode into contact with the liquid to be measured again and measuring the oxidation-reduction potential of the liquid to be measured;
A method for measuring an oxidation-reduction potential is provided.

  According to the present invention, after measuring the oxidation-reduction potential, the electrode can be cleaned by contacting with the cleaning liquid in the cleaning tank, and the oxidation-reduction potential can be measured again. The electrode is removable, and can be placed in either the measurement tank or the cleaning tank by attaching the electrode to either the first electrode attachment portion or the second electrode attachment portion. For this reason, even when hydrogen is adsorbed or occluded on the electrode surface, it can be removed and measurement can be performed again. Therefore, the redox potential can be measured stably for a long period.

  In the present invention, while supplying the liquid to be measured into the measurement tank, the excess of the liquid to be measured overflows and is discharged from above the position where the electrode is installed. The potential can be measured. If it carries out like this, it can measure, replacing the to-be-measured liquid in a measuring tank, contacting an electrode to a to-be-measured liquid. For this reason, the time-dependent change of the oxidation-reduction potential of the liquid to be measured can be stably measured for a long time.

  In the present invention, the liquid to be measured can be reduced water. By doing so, the redox potential of the reduced water can be stably measured. Therefore, it is possible to reliably grasp the redox potential of reduction. In this specification, reduced water is water having a higher reducing action than pure water. For example, hydrogen water obtained by dissolving hydrogen gas in pure water or electrolyzed water obtained by electrolyzing pure water is used. Can be mentioned. The oxidation-reduction potential of the reduced water is, for example, less than 0 mV, and more specifically can be set to −1 V or more and −500 mV or less. Here, the oxidation-reduction potential is described as a value using a silver / silver chloride electrode, and in order to convert to a value using a standard hydrogen electrode, a correction value at the assumed temperature (usually about +200 mV) is used. What is necessary is just to add. The hydrogen ion concentration of the reducing water is, for example, pH 6.5 or more and 14 or less.

  It should be noted that any combination of these components, or a conversion of the expression of the present invention between a method, an apparatus, and the like is also effective as an aspect of the present invention.

  For example, according to the present invention, there is provided an oxidation-reduction potential measurement system including the oxidation-reduction potential measurement device and a control unit that controls measurement of the oxidation-reduction potential.

  According to the present invention, the electrode for measuring the oxidation-reduction potential of the liquid to be measured is brought into contact with the liquid to be measured, the redox potential of the liquid to be measured is measured, and the redox potential is measured. The measurement liquid is discharged from the vicinity of the bottom of the measurement tank, the surface of the electrode is exposed, and then the measurement liquid is supplied from the vicinity of the bottom of the measurement tank, and the electrode is again contacted with the measurement liquid. An oxidation-reduction potential measurement system is provided that is controlled to be controlled.

  According to the present invention, the oxidation-reduction potential can be stably measured with a simple configuration.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following embodiment, a case where an oxidation-reduction potential measuring device is used for monitoring the oxidation-reduction potential for controlling the quality of the reduced water will be described as an example. Moreover, in all drawings, the same code | symbol is attached | subjected to the same component and description is abbreviate | omitted suitably.

(First embodiment)
FIG. 1 is a cross-sectional view showing the configuration of the oxidation-reduction potential measuring apparatus of this embodiment. The oxidation-reduction potential measuring apparatus 100 shown in FIG. 1 is in contact with the measurement tank 101 that stores the liquid to be measured (reduced water 115) that is the target of measurement of the oxidation-reduction potential, and the reduced water 115 in the measurement tank 101. An electrode (working electrode 105, reference electrode 107) that is disposed and measures the oxidation-reduction potential of the reducing water 115 and a supply port (liquid) that is provided near the bottom of the measuring tank 101 and supplies the reducing water 115 to the measuring tank 101 A communication port of the supply pipe 109) and a discharge port (a communication port of the drain pipe 111) provided near the bottom of the measurement tank 101 and discharging the reducing water 115 from the measurement tank 101.
Above the communication port of the liquid supply pipe 109, an excess liquid discharge port (a communication port of the overflow pipe 113) that discharges excess reducing water 115 in the measurement tank 101 by overflowing is provided. The working electrode 105 and the reference electrode 107 are disposed below the communication port of the overflow pipe 113.
The communication port of the overflow pipe 113 may be provided on a part of the wall surface of the measurement tank 101 as shown in FIG.

  Hereinafter, the configuration of the oxidation-reduction potential measuring apparatus 100 will be described in more detail. The oxidation-reduction potential measuring apparatus 100 includes a measurement tank 101, a sensor 103 disposed at a predetermined position in the measurement tank 101, a liquid supply pipe 109 that supplies the reduction water 115 to the measurement tank 101, and reduced water 115 from the sensor 103. It has a drain pipe 111 and an overflow pipe 113 for discharging.

  The shape of the measuring tank 101 is, for example, a rectangular parallelepiped, and the size thereof is, for example, about 15 cm in width at the bottom, about 10 cm in depth, and about 10 cm in height.

  The liquid supply pipe 109 is inserted into the measurement tank 101 from the bottom surface of the measurement tank 101 and communicates with the measurement tank 101. The liquid supply pipe 109 may be provided with a flow rate adjusting member (not shown) such as a valve for adjusting the supply amount of the reducing water 115. The drain pipe 111 is also inserted into the measurement tank 101 from the bottom surface of the measurement tank 101 and communicates with the measurement tank 101. The overflow pipe 113 is inserted into the measurement tank 101 from the side surface of the measurement tank 101 and communicates with the measurement tank 101. The fixing position of the overflow pipe 113 is a position higher than the positions of the working electrode 105 and the reference electrode 107 when the sensor 103 is arranged in the measurement tank 101. By doing so, the height of the liquid surface 117 of the reducing water 115 in the measuring tank 101 when monitoring the oxidation-reduction potential is sufficiently secured, and the working electrode 105 and the reference electrode 107 are reliably brought into contact with the reducing water 115. I can leave.

  The oxidation-reduction potential measuring apparatus 100 is configured to be able to switch between drainage from the drain pipe 111 and drainage from the overflow pipe 113. For example, a valve (first reduced water discharge valve 159 and second reduced water discharge valve 161 in FIG. 13) is provided in each of the drain pipe 111 and the overflow pipe 113 so that one valve is opened and the other valve is opened. It can also be in a closed state.

  The sensor 103 is a redox potential measurement sensor, and has a working electrode 105 and a reference electrode 107 as electrodes. In the present embodiment and the following embodiments, a case where the electrode of the sensor 103 is a bipolar type composed of a working electrode and a reference electrode will be described as an example. It can also be set as a three-pole type provided with. In the present embodiment and the following embodiments, for example, the working electrode is platinum (Pt), and the reference electrode is an Ag-AgCl electrode having an internal liquid of 3.3 mol / L KCl.

Next, a method for measuring the redox potential of the reduced water 115 using the redox potential measuring apparatus 100 will be described.
The measurement method of the present embodiment includes the following steps.
Step 101: Contacting the electrode (working electrode 105, reference electrode 107) for measuring the oxidation-reduction potential of the liquid to be measured (reduced water 115) with the reduced water 115 and measuring the oxidation-reduction potential of the reduced water 115;
Step 102: After the step of measuring the oxidation-reduction potential (step 101), the step of discharging the reducing water 115 from the vicinity of the bottom of the measurement tank 101 to expose the surfaces of the working electrode 105 and the reference electrode 107, and step 103: After the step of exposing the surfaces of the working electrode 105 and the reference electrode 107 (step 102), the reducing water 115 is supplied from the vicinity of the bottom of the measuring tank 101, and the working electrode 105 and the reference electrode 107 are brought into contact with the reducing water 115. ,
including.
In the step of measuring the oxidation-reduction potential of the liquid to be measured in step 101, while supplying the reduced water 115 into the measurement tank 101, the excess reduced water 115 is removed from above the installation position of the working electrode 105 and the reference electrode 107. This is a step of measuring the oxidation-reduction potential of the reduced water 115 while making it overflow and discharge.

Hereinafter, the oxidation-reduction potential measurement method of this embodiment will be described in more detail.
First, the sensor 103 is installed in the measurement tank 101 and the reducing water 115 is fed from the liquid supply pipe 109. At this time, since the overflow pipe 113 is provided at a predetermined position higher than the installation positions of the working electrode 105 and the reference electrode 107, an excessive amount of reducing water 115 is discharged from the overflow pipe 113 to the outside of the measuring tank 101. . Therefore, the height of the liquid surface 117 is kept substantially constant.

  Then, the redox potential of the reduced water 115 is measured by the sensor 103 (step 101). When the monitoring time of the oxidation-reduction potential becomes longer, bubbles 119 adhere to the surface of the sensor 103. Therefore, the bubble 119 is removed at a predetermined timing. Specifically, drainage from the overflow pipe 113 is stopped and switched to drainage from the drain pipe 111. Then, the reducing water 115 is discharged from the vicinity of the bottom surface of the measuring tank 101 to the outside of the measuring tank 101, the position of the liquid surface 117 is lowered, and the surfaces of the working electrode 105 and the reference electrode 107 are exposed (step 102).

  After exposing the surfaces of the working electrode 105 and the reference electrode 107, the drainage from the drain pipe 111 is stopped, and the reducing water 115 is supplied again from the liquid supply pipe 109 into the measuring tank 101. The electrode 107 is brought into contact with the reducing water 115 (step 103). Thereafter, the redox potential measurement is repeated according to the procedure described above.

Next, the effect of the oxidation-reduction potential measuring apparatus 100 will be described.
In the oxidation-reduction potential measuring apparatus 100, a drain pipe 111 is provided on the bottom surface of the measurement tank 101. For this reason, when bubbles 119 adhere to the surface of the sensor 103, the reducing water 115 is once discharged from the drain pipe 111 to expose the surfaces of the working electrode 105 and the reference electrode 107, and then contacted with the reducing water 115 again. be able to. Therefore, the oxidation-reduction potential measuring apparatus 100 can remove the bubbles 119 by discharging the reducing water 115 and exposing the electrode surface. Therefore, the redox potential of the reduced water 115 can be stably measured for a long time.

  For example, when the measurement of the oxidation-reduction potential of the reduced water 115 is continued without performing the waste liquid from the drain pipe 111, the oxidation-reduction potential indicating −0.75 V is −0 after several hours after the measurement starts. Only about 3V may be shown. In addition, when monitoring the oxidation-reduction potential of the reduced water 115 supplied from the reduced water production apparatus to the semiconductor cleaning apparatus, a pipe for supplying the reduced water 115 to the main body of the semiconductor cleaning apparatus is connected to a pH / ORP measurement unit. Although branched, hydrogen gas tends to adhere to the sensor 103 because the flow rate of the reducing water 115 flowing through the ORP measurement unit (measurement tank 101) is small. In particular, platinum used as an electrode material is a hydrogen-occlusion metal, and therefore easily attracts hydrogen gas.

  Thus, in the present embodiment, the bubbles 119 attached to the sensor 103 can be easily and reliably removed by discharging and refilling the reducing water 115 at a predetermined timing. For this reason, the oxidation-reduction potential of the reduced water 115 can be stably measured for a long period.

  The oxidation-reduction potential measuring apparatus 100 may include a control unit that controls opening and closing of the liquid supply pipe 109, the drain pipe 111, and the overflow pipe 113. In this way, the discharge path can be automatically adjusted so that the electrode surface of the sensor 103 can be more easily exposed and brought into contact with the reduced water 115 again.

  1 illustrates the oxidation-reduction potential measuring apparatus 100 having two drain pipes of the drain pipe 111 and the overflow pipe 113. However, the oxidation-reduction potential measuring apparatus 100 is at least near the bottom surface of the measurement tank 101. What is necessary is just to have the drain pipe 111 provided.

  FIG. 2 is a cross-sectional view showing the configuration of the oxidation-reduction potential measuring apparatus having such a configuration. The basic configuration of the oxidation-reduction potential measurement apparatus 110 shown in FIG. 2 is the same as that of the oxidation-reduction potential measurement apparatus 100 shown in FIG. 1 except that the overflow pipe 113 is not provided. In the case where the overflow pipe 113 is not provided as in the oxidation-reduction potential measuring apparatus 110, the reducing water 115 may be supplied under a pressure of, for example, about 0.2 to 0.3 MPa. In this way, the height of the liquid surface 117 can be more stably maintained on the electrode.

  Further, like the oxidation-reduction potential measuring apparatus 100 shown in FIG. 1, the configuration further including the overflow pipe 113 further ensures that the height of the liquid surface 117 during monitoring of the oxidation-reduction potential is at a predetermined position. Can be maintained. Therefore, the redox potential can be measured more stably for a long period.

  In the following embodiment, it demonstrates centering on a different point from the oxidation-reduction potential measuring apparatus (FIG. 1 or FIG. 2) described in 1st embodiment.

(Second embodiment)
FIG. 3 is a cross-sectional view showing a configuration of the oxidation-reduction potential measuring apparatus of the present embodiment. The oxidation-reduction potential measuring apparatus 200 shown in FIG. 3 is in contact with the measurement tank 201 that stores the liquid to be measured (reduced water 215) that is the target for measuring the oxidation-reduction potential, and the reduced water 215 in the measurement tank 201. An electrode (working electrode 205, reference electrode 207) that is disposed and measures the oxidation-reduction potential of the reduced water 215, and a supply port (liquid) that is provided near the bottom of the measurement tank 201 and supplies the reduced water 215 to the measurement tank 201 A communication port of the supply pipe 209), an excess liquid discharge port (a communication port of the overflow pipe 213) that is provided in the measurement tank 201 and discharges the excess reduced water 215 in the measurement tank 201. Vibration means (vibrating plate 221) for applying vibration to the reduced water 215. The working electrode 205 and the reference electrode 207 are disposed below the communication port of the overflow pipe 213.

  Hereinafter, the configuration of the oxidation-reduction potential measuring apparatus 200 of FIG. 3 will be described in more detail. The oxidation-reduction potential measuring device 200 includes a measurement tank 201, a sensor 203 disposed at a predetermined position in the measurement tank 201, a liquid supply pipe 209 that supplies the reduced water 215 to the measurement tank 201, and reduced water 215 from the measurement tank 201. An overflow pipe 213 for discharging and a diaphragm 221 provided at the bottom of the measurement tank 201 are provided. The sensor 203 is a redox potential sensor, and has a working electrode 205 and a reference electrode 207 as electrodes.

  The liquid supply pipe 209 is inserted into the measurement tank 201 from the bottom surface of the measurement tank 201 and communicates with the measurement tank 201. The liquid supply pipe 209 may be provided with a flow rate adjusting member (not shown) such as a valve for adjusting the supply amount of the reducing water 215. The overflow pipe 213 is inserted into the measurement tank 201 from the side surface of the measurement tank 201 and communicates with the measurement tank 201. The fixing position of the overflow pipe 213 is a position higher than the positions of the working electrode 205 and the reference electrode 207 when the sensor 203 is arranged in the measurement tank 201. By doing so, the height of the liquid surface 217 of the reduced water 215 in the measurement tank 201 when monitoring the oxidation-reduction potential is kept sufficiently high with respect to the electrodes, and the working electrode 205 and the reference electrode 207 are securely attached to the reduced water 215. Can continue to touch.

Next, a method for measuring the redox potential of the reduced water 215 using the redox potential measuring apparatus 200 will be described.
In the present embodiment, while the electrodes (working electrode 205, reference electrode 207) for measuring the redox potential of the liquid to be measured (reduced water 215) are in contact with the reduced water 215, the reduced water 215 is vibrated. Then, the redox potential of the reduced water 215 is measured.

Hereinafter, the oxidation-reduction potential measurement method of this embodiment will be described in more detail.
First, the sensor 203 is installed in the measurement tank 201 and the reducing water 215 is fed from the liquid supply pipe 209. At this time, since the overflow pipe 213 is provided at a predetermined position higher than the installation positions of the working electrode 205 and the reference electrode 207, an excessive amount of reduced water 215 is discharged from the overflow pipe 213 to the outside of the measurement tank 201. .

  Then, the redox potential of the reduced water 215 is measured by the sensor 203. At this time, the vibration plate 221 is operated to perform measurement while generating the vibration wave 223 in the measurement tank 201.

Next, the effect of this embodiment will be described.
The oxidation-reduction potential measuring apparatus 200 is provided with a vibration plate 221 at the bottom of the measurement tank 201, and can generate a vibration wave 223 in the measurement tank 201 by vibrating the vibration plate 221. For this reason, the energy of the vibration wave 223 can prevent the hydrogen gas in the reduced water 215 from adhering to the surface of the sensor 203 as the bubbles 219, and the attached bubbles 219 can be reliably removed. Therefore, the redox potential of the reduced water 215 can be stably measured.

  3 exemplifies a configuration in which the diaphragm 221 is disposed on the bottom surface of the measurement tank 201, the position where the diaphragm 221 is provided is not limited to the bottom surface of the measurement tank 201. It can also be provided on the side surface of the measuring tank 201.

  Further, in the oxidation-reduction potential measuring apparatus 200 of FIG. 3, in addition to the overflow pipe 213, the oxidation-reduction potential measuring apparatus 100 (FIG. 1) described in the first embodiment is further added to the bottom surface of the measurement tank 201. Another drain pipe may be provided.

  FIG. 4 is a cross-sectional view showing the oxidation-reduction potential measuring apparatus having such a configuration. The basic configuration of the oxidation-reduction potential measurement device 210 shown in FIG. 4 is the same as that of the oxidation-reduction potential measurement device 200 of FIG. 3, but further, a drain pipe 211 is provided on the bottom surface of the measurement tank 201, and the drain pipe 211 and overflow The discharge from the pipe 213 is configured to be switchable. According to the oxidation-reduction potential measuring device 210, in addition to the effect of removing the bubbles 219 using the vibration plate 221, the reduced water 215 can be discharged from the drain pipe 211 and supplied again. For this reason, the bubble 219 adhering to the sensor 203 can be more reliably removed.

(Third embodiment)
FIG. 5 is a cross-sectional view showing a configuration of the oxidation-reduction potential measuring apparatus of the present embodiment. The oxidation-reduction potential measuring apparatus 300 shown in FIG. 5 is disposed so as to be in contact with a measurement tank 301 that stores a liquid to be measured whose oxidation-reduction potential is to be measured, and reduced water 315 in the measurement tank 301. An electrode (working electrode 305, reference electrode 307) that measures the oxidation-reduction potential of 315 and a supply port (communication of the liquid supply pipe 309) that is provided in the vicinity of the bottom of the measurement tank 301 and supplies the reducing water 315 to the measurement tank 301 A surplus liquid discharge port (a communication port of the overflow pipe 313) that is provided in the measurement tank 301 and discharges the excess reduced water 315 in the measurement tank 301, and the reduced water 315 in the measurement tank 301. Stirring means (stirrer 321 and stirrer 323). The working electrode 305 and the reference electrode 307 are disposed below the communication port of the overflow pipe 313. As the stirrer 321, a magnetic stirrer can be used.

  Hereinafter, the configuration of the oxidation-reduction potential measuring apparatus 300 in FIG. 5 will be described in more detail. The oxidation-reduction potential measuring apparatus 300 includes a measurement tank 301, a sensor 303 arranged at a predetermined position in the measurement tank 301, a liquid supply pipe 309 that supplies the reduced water 315 to the measurement tank 301, and reduced water 315 from the measurement tank 301. It has an overflow pipe 313 to be discharged, a stirrer 321 provided at the lower part of the measurement tank 301, and a stirrer 323 disposed on the stirrer 321 via the bottom surface of the measurement tank 301 while being disposed on the bottom surface of the measurement tank 301. The stirrer 321 is installed below the arrangement area of the sensor 303. The sensor 303 is an oxidation-reduction potential sensor, and has a working electrode 305 and a reference electrode 307 as electrodes.

  The liquid supply pipe 309 is inserted into the measurement tank 301 from the bottom surface of the measurement tank 301 and communicates with the measurement tank 301. The liquid supply pipe 309 may be provided with a flow rate adjusting member (not shown) such as a valve for adjusting the supply amount of the reducing water 315. The overflow pipe 313 is inserted into the measurement tank 301 from the side surface of the measurement tank 301 and communicates with the measurement tank 301. The fixed position of the overflow pipe 313 is set to a position higher than the positions of the working electrode 305 and the reference electrode 307 when the sensor 303 is arranged in the measurement tank 301. By doing so, the height of the liquid surface 317 of the reduced water 315 in the measurement tank 301 at the time of monitoring the oxidation-reduction potential is kept sufficiently high with respect to the electrodes, and the working electrode 305 and the reference electrode 307 are reliably attached to the reduced water 315. Can continue to touch.

Next, a method for measuring the redox potential of the reduced water 315 using the redox potential measuring apparatus 300 will be described.
In the present embodiment, while the electrode (working electrode 305, reference electrode 307) for measuring the oxidation-reduction potential of the liquid to be measured (reduced water 315) is in contact with the reduced water 315, the reduced water 315 is stirred, The redox potential of the reduced water 315 is measured.

Hereinafter, the oxidation-reduction potential measurement method of this embodiment will be described in more detail.
First, the sensor 303 is installed in the measurement tank 301, and reducing water 315 is sent from the liquid supply pipe 309. At this time, since the overflow pipe 313 is provided at a predetermined position higher than the installation positions of the working electrode 305 and the reference electrode 307, an excessive amount of reduced water 315 is discharged from the overflow pipe 313 to the outside of the measurement tank 301. .

  Then, the redox potential of the reduced water 315 is measured by the sensor 303. At this time, the stirrer 321 is operated, the stirrer 323 is rotated on the bottom surface of the measurement tank 301, and measurement is performed while stirring the reduced water 315.

Next, the effect of this embodiment will be described.
In the oxidation-reduction potential measuring apparatus 300, a stirrer 321 is provided in the lower part of the measurement tank 301, and the stirrer 323 is rotated in the measurement tank 301 by operating the stirrer 321, whereby the reduced water 315 can be stirred. . For this reason, the flow of the reduced water 315 generated by the stirring of the stirrer 323 prevents the hydrogen gas in the reduced water 315 from adhering to the surface of the sensor 303 as the bubbles 319 and reliably removes the attached bubbles 319. Can do. Therefore, the redox potential of the reduced water 315 can be stably measured.

  In the oxidation-reduction potential measuring apparatus 300, the shape of the stirrer 323 is not particularly limited, but may be a disk shape, for example. In this way, the stirrer 323 can be more stably held on the stirrer 321 and rotated. Therefore, the bubbles 319 can be removed more reliably.

  In addition to the overflow pipe 313, the oxidation-reduction potential measurement apparatus 300 in FIG. 5 is further provided on the bottom surface of the measurement tank 301 in the same manner as the oxidation-reduction potential measurement apparatus 100 (FIG. 1) described in the first embodiment. Another drain pipe may be provided.

  FIG. 6 is a cross-sectional view showing an oxidation-reduction potential measuring apparatus having such a configuration. The basic configuration of the oxidation-reduction potential measurement device 310 shown in FIG. 6 is the same as that of the oxidation-reduction potential measurement device 300 of FIG. 5, but a drain pipe 311 is further provided on the bottom surface of the measurement tank 301. The discharge from the pipe 313 is configured to be switchable. According to the oxidation-reduction potential measuring device 310, in addition to the effect of removing the bubbles 319 using the stirrer 321, the reduced water 315 can be discharged from the drain pipe 311 and supplied again. For this reason, the bubble 319 adhering to the sensor 303 can be more reliably removed.

(Fourth embodiment)
FIG. 7 is a cross-sectional view showing the configuration of the oxidation-reduction potential measuring apparatus of the present embodiment. The oxidation-reduction potential measuring apparatus 400 shown in FIG. 7 is in contact with the measurement tank 401 that stores the liquid to be measured (reduced water 415) to be measured for the oxidation-reduction potential, and the reduced water 415 in the measurement tank 401. An electrode (working electrode 405, reference electrode 407) that is disposed and measures the oxidation-reduction potential of the reduced water 415, and a supply port (liquid) that supplies the reduced water 415 to the measurement tank 401 provided near the bottom of the measurement tank 401 A communication port of the supply pipe 409), an excess liquid discharge port (a communication port of the overflow pipe 413) that is provided in the measurement tank 401 and discharges the excess reduced water 415 in the measurement tank 401. In the vicinity of the working electrode 405 and the reference electrode 407 disposed therein, a gas supply unit (inert gas supply pipe 421) for introducing an inert gas (N ₂ gas 423) is provided.
The working electrode 405 and the reference electrode 407 are disposed below the communication port of the overflow pipe 413.

  Hereinafter, the configuration of the oxidation-reduction potential measuring apparatus 400 of FIG. 7 will be described in more detail. The oxidation-reduction potential measuring device 400 includes a measurement tank 401, a sensor 403 disposed at a predetermined position in the measurement tank 401, a liquid supply pipe 409 that supplies the reduced water 415 to the measurement tank 401, and the reduced water 415 from the measurement tank 401. And an inert gas supply pipe 421 that is introduced into the measurement tank 401 from the side surface of the measurement tank 401 and communicates with the measurement tank 401. The sensor 403 is an oxidation-reduction potential sensor, and has a working electrode 405 and a reference electrode 407 as electrodes.

  The liquid supply pipe 409 is inserted into the measurement tank 401 from the bottom surface of the measurement tank 401 and communicates with the measurement tank 401. The liquid supply pipe 409 may be provided with a flow rate adjusting member (not shown) such as a valve for adjusting the supply amount of the reducing water 415. The overflow pipe 413 is inserted into the measurement tank 401 from the side surface of the measurement tank 401 and communicates with the measurement tank 401. The fixed position of the overflow pipe 413 is a position higher than the positions of the working electrode 405 and the reference electrode 407 when the sensor 403 is disposed in the measurement tank 401. By doing so, the height of the liquid surface 417 of the reduced water 415 in the measurement tank 401 at the time of monitoring the oxidation-reduction potential is kept sufficiently high with respect to the electrode, and the working electrode 405 and the reference electrode 407 are reliably attached to the reduced water 415. Can continue to touch.

The tip of the inert gas supply pipe 421 is disposed below the sensor 403, and an inert gas such as N ₂ gas 423 is supplied from the tip into the measurement tank 401. In addition, the other end of the inert gas supply pipe 421 is connected to an inert gas storage unit such as an N ₂ cylinder.

Next, a method for measuring the redox potential of the reduced water 415 using the redox potential measuring device 400 will be described.
In the present embodiment, electrodes (working electrode 405, reference electrode 407) for measuring the oxidation-reduction potential of the liquid to be measured (reduced water 415) are brought into contact with the reduced water 415, and in the vicinity of the working electrode 405 and the reference electrode 407. While introducing an inert gas (N ₂ gas 423), the redox potential of the reduced water 415 is measured.

Hereinafter, the oxidation-reduction potential measurement method of this embodiment will be described in more detail.
First, the sensor 403 is installed in the measurement tank 401, and reducing water 415 is sent from the liquid supply pipe 409. At this time, since the overflow pipe 413 is provided at a predetermined position higher than the installation positions of the working electrode 405 and the reference electrode 407, an excessive amount of reduced water 415 is discharged from the overflow pipe 413 to the outside of the measuring tank 401. .

Then, the redox potential of the reduced water 415 is measured by the sensor 403. At this time, the inert gas supply pipe 421 is operated, and measurement is performed while N ₂ gas 423 is ejected from below the sensor 403. The supply method of the N ₂ gas 423 is, for example, intermittent bubbling.

Next, the effect of this embodiment will be described.
The oxidation-reduction potential measuring device 400 includes an inert gas supply pipe 421 and is configured such that the tip of the inert gas supply pipe 421 is positioned below the sensor 403. For this reason, the oxidation-reduction potential can be measured while N ₂ gas 423 is ejected from below the sensor 403. The N ₂ gas 423 is a gas that does not affect the redox potential of the reduced water 415. For this reason, by measuring such a gas while bubbling, it is possible to suppress the bubble 419 from adhering to the surface of the sensor 403 due to the air flow of the N ₂ gas 423 and to reliably remove the bubble 419 attached. it can. Therefore, the redox potential of the reduced water 415 can be stably measured.

(Fifth embodiment)
FIG. 8 is a cross-sectional view showing the configuration of the oxidation-reduction potential measuring apparatus of this embodiment. The oxidation-reduction potential measuring apparatus 500 shown in FIG. 8 is in contact with the measurement tank 501 that contains the liquid to be measured (reduced water 515) that is the target for measuring the oxidation-reduction potential, and the reduced water 515 in the measurement tank 501. An electrode (working electrode 505, reference electrode 507) that is disposed and measures the oxidation-reduction potential of the reducing water 515, and a supply port (liquid) that supplies the reducing water 515 to the measuring tank 501 provided near the bottom of the measuring tank 501. A communication port of the supply pipe 509), an excess liquid discharge port (a communication port of the overflow pipe 513) that is provided in the measurement tank 501 and discharges the excess reduced water 515 in the measurement tank 501, and the measurement tank 501. The liquid feed section (liquid feed pipe 509, pump 523, overflow pipe 513, liquid feed pipe 509 feeds the reduced water 515 into the measuring tank 501 from the communication port of the liquid feed pipe 509 so that the inside of the chamber becomes positive pressure with respect to the outside. With an amount adjusting valve 521), the.
The working electrode 505 and the reference electrode 507 are disposed below the communication port of the overflow pipe 513. The communication port of the overflow pipe 513 is provided in the vicinity of the upper surface of the measurement tank 501.
Moreover, the measurement tank 501 has a sealed structure.
The liquid feeding unit makes the supply rate of the reduced water 515 from the communication port of the liquid supply pipe 509 to the measurement tank 501 larger than the discharge rate of the reduced water 515 from the communication port of the overflow pipe 513.
The pump 523 pumps the reducing water 515 in the liquid supply pipe 509 to the measurement tank 501.
The flow rate adjustment valve 521 is provided in the overflow pipe 513 and adjusts the discharge speed of the reduced water 515 from the communication port of the overflow pipe 513.

  Hereinafter, the configuration of the oxidation-reduction potential measuring apparatus 500 of FIG. 8 will be described in more detail. The oxidation-reduction potential measuring device 500 is provided in a measurement tank 501, a sensor 503 disposed at a predetermined position in the measurement tank 501, a liquid supply pipe 509 for supplying reduced water 515 to the measurement tank 501, and a liquid supply pipe 509. It has a pump 523, an overflow pipe 513 that discharges the reduced water 515 from the measurement tank 501, and a flow rate adjustment valve 521 provided in the overflow pipe 513. The sensor 503 is an oxidation-reduction potential sensor, and has a working electrode 505 and a reference electrode 507 as electrodes.

  The liquid supply pipe 509 is inserted into the measurement tank 501 from the bottom surface of the measurement tank 501 and communicates with the measurement tank 501. The liquid supply pipe 509 may be provided with a flow rate adjusting member (not shown) such as a valve for adjusting the supply amount of the reducing water 515. The pump 523 has a function of pumping the reducing water 515 supplied from the liquid supply pipe 509 into the measurement tank 501 and pressurizing the measurement tank 501. The overflow pipe 513 is inserted into the measurement tank 501 from the vicinity of the upper surface of the measurement tank 501 and communicates with the measurement tank 501. Since the overflow pipe 513 is fixed near the upper surface of the measurement tank 501, the measurement tank 501 can be filled with the reduced water 515.

Next, a method for measuring the redox potential of the reduced water 515 using the redox potential measuring apparatus 500 will be described.
In the present embodiment, the electrodes (working electrode 505, reference electrode 507) for measuring the oxidation-reduction potential of the liquid to be measured (reduced water 515) are in contact with the reduced water 515 in the sealed measurement tank 501. The oxidation-reduction potential of the reduced water 515 is measured by setting the inside of the measurement tank 501 to be more positive than the outside of the measurement tank 501.

Hereinafter, the oxidation-reduction potential measurement method of this embodiment will be described in more detail.
First, the sensor 503 is installed in the measurement tank 501, and the reducing water 515 is sent from the liquid supply pipe 509. At this time, the reduced water 515 is pressurized using the pump 523 according to the drainage speed | rate from the overflow pipe | tube 513 as needed. As described above, since the overflow pipe 513 is provided in the vicinity of the upper surface of the measurement tank 501, the inside of the measurement tank 501 is filled with almost 100% reduced water 515, and the water level is kept constant.

  Then, the redox potential of the reduced water 515 is measured by the sensor 503. At this time, the flow rate adjustment valve 521 is adjusted to adjust the discharge rate of the reduced water 515 from the overflow pipe 513. Specifically, the flow rate adjustment valve 521 is squeezed so that the inside of the measurement tank 501 is sufficiently pressurized, and the discharge speed is reduced.

Next, the effect of this embodiment will be described.
The oxidation-reduction potential measuring apparatus 500 has a flow rate adjustment valve 521. For this reason, the flow rate adjusting valve 521 can be adjusted so that the discharge rate of the reduced water 515 from the overflow pipe 513 can be made sufficiently smaller than the supply rate from the liquid supply pipe 509. In addition, since the pump 523 is included, the reduced water 515 can be pumped to the measurement tank 501 at a predetermined speed. For this reason, it is possible to maintain the reduced water 515 in the measurement tank 501 in a pressurized state with a simple configuration. By keeping the inside of the measurement tank 501 pressurized, the hydrogen gas in the reduced water 515 can be prevented from becoming bubbles 519 and the bubbles 519 can be prevented from adhering to the surface of the sensor 503.

  As described above, the oxidation-reduction potential measuring apparatus 500 includes a liquid feeding unit that functions as a foam suppression unit, and the liquid feeding unit including the liquid supply pipe 509, the pump 523, the overflow pipe 513, and the flow rate adjustment valve 521 is a measurement tank. Since the reducing water 515 in the 501 is pressurized, the generation of bubbles in the reducing water 515 can be effectively suppressed with a simple configuration, and the redox potential of the reducing water 513 can be stably measured. This effect is remarkably exhibited when the liquid supply pipe 509 is provided with a pump 523 and is supplied from the liquid supply pipe 509 to the measurement tank 501 under pressure.

(Sixth embodiment)
FIG. 9 is a cross-sectional view showing the configuration of the oxidation-reduction potential measuring apparatus of this embodiment. The oxidation-reduction potential measuring apparatus 600 shown in FIG. 9 is in contact with the measurement tank 601 that contains the measurement target liquid (reduced water 615) that is the target for measuring the oxidation-reduction potential, and the reduced water 615 in the measurement tank 601. An electrode (working electrode 605, reference electrode 607) that is disposed and measures the oxidation-reduction potential of the reducing water 615, and a supply port (liquid) that supplies the reducing water 615 to the measuring tank 601 provided near the bottom of the measuring tank 601. A communication port of the supply pipe 609), an excess liquid discharge port (a communication port of the overflow pipe 613) that is provided in the measurement tank 601 and discharges the excess reduced water 615 in the measurement tank 601. Cooling means (cooler 621) for cooling the air.
The working electrode 605 and the reference electrode 607 are disposed below the communication port of the overflow pipe 613.

  Hereinafter, the configuration of the oxidation-reduction potential measuring apparatus 600 of FIG. 9 will be described in more detail. The oxidation-reduction potential measuring device 600 is in contact with the measurement tank 601, the sensor 603 disposed at a predetermined position in the measurement tank 601, the liquid supply pipe 609 that supplies the reducing water 615 to the measurement tank 601, and the liquid supply pipe 609. A cooler 621 that cools the liquid supply pipe 609 and the reducing water 515 inside the liquid supply pipe 609 is provided. The sensor 603 is a redox potential sensor, and has a working electrode 605 and a reference electrode 607 as electrodes. The sensor 603 includes a calibration unit (not shown) that performs temperature calibration of the measurement value.

  The liquid supply pipe 609 is inserted into the measurement tank 601 from the bottom surface of the measurement tank 601 and communicates with the measurement tank 601. The liquid supply pipe 609 may be provided with a flow rate adjusting member (not shown) such as a valve for adjusting the supply amount of the reducing water 615. The overflow pipe 613 is inserted into the measurement tank 601 from the side surface of the measurement tank 601 and communicates with the measurement tank 601. The fixing position of the overflow pipe 613 is higher than the positions of the working electrode 605 and the reference electrode 607 when the sensor 603 is arranged in the measurement tank 601. By doing this, the height of the liquid surface 617 of the reduced water 615 in the measuring tank 601 when monitoring the oxidation-reduction potential is kept sufficiently high, and the working electrode 405 and the reference electrode 607 are reliably kept in contact with the reduced water 615. be able to.

Next, a method for measuring the redox potential of the reduced water 615 using the redox potential measuring apparatus 600 will be described.
In the present embodiment, in a state in which the liquid to be measured (reduced water 615) is cooled, the electrode (working electrode 605, reference electrode 607) for measuring the oxidation-reduction potential of the reduced water 615 is brought into contact with the reduced water 615 for reduction. The redox potential of water 615 is measured.

Hereinafter, the oxidation-reduction potential measurement method of this embodiment will be described in more detail.
First, the sensor 603 is installed in the measurement tank 601, and the reducing water 615 is sent from the liquid supply pipe 609. At this time, the cooler 621 is operated to cool the reduced water 615 and supply it to the measurement tank 601. The cooling temperature is set to a temperature at which the reduced water 615 is not frozen. Further, the temperature can be set as low as possible within a range not to be frozen, for example, 10 ° C. or less, preferably 5 ° C. or less. Then, the redox potential of the reduced water 615 is measured by the sensor 603. At this time, temperature calibration of the measured value is performed in a calibration unit (not shown).

  In this embodiment as well, since the overflow pipe 613 is provided at a predetermined position higher than the installation positions of the working electrode 605 and the reference electrode 607, an excessive amount of reduced water 615 flows from the overflow pipe 613 to the measuring tank 601. It is discharged outside. Therefore, the height of the liquid level 617 is kept substantially constant.

Next, the effect of the oxidation-reduction potential measuring apparatus 600 will be described.
The oxidation-reduction potential measuring apparatus 600 is configured to cool the reducing water 615 with a cooler 621 and continuously supply it to the measurement tank 601. For this reason, the oxidation-reduction potential can be measured in a state where the inside of the measurement tank 601 is cooled. Therefore, hydrogen gas dissolved in the reducing water 615 in the measurement tank 601 can be effectively suppressed from becoming bubbles 619. Therefore, it is possible to suppress the bubble 619 from adhering to the surface of the sensor 603 during the measurement of the redox potential and stably perform the redox potential measurement.

  In the oxidation-reduction potential measuring apparatus 600 shown in FIG. 9, the configuration in which the liquid supply pipe 609 is provided with the cooler 621 as an in-line cooler is illustrated, but in addition to the cooler 621, the measurement tank 601 is further cooled. A cooler may be provided. By so doing, the reduced water 615 in the measurement tank 601 can be cooled more reliably, and the generation of bubbles 619 can be further effectively suppressed. Moreover, only the cooler which cools the measurement tank 601 can also be used.

(Seventh embodiment)
The oxidation-reduction potential measuring device described in the above embodiment may have a mechanism for bringing the sensor electrode into contact with an acidic liquid or an oxidizing liquid. Hereinafter, a case where the configuration of the oxidation-reduction potential measurement device (FIGS. 1 and 2) described in the first embodiment is used as a basic configuration will be described as an example. However, the oxidation-reduction potential measurement device described in other embodiments will be described. It can be applied to the configuration of the present embodiment, or can be combined with the configuration of the present embodiment.

First, a description will be given of an example of a type of oxidation-reduction potential measurement device that cleans a sensor electrode in a measurement tank, in which the cleaning liquid is ozone water, and the oxidation-reduction potential measurement device is applied to a reduced water production system. FIG. 10 is a diagram showing a configuration of the reduced water production system of the present embodiment. A reduction water production system 700 shown in FIG. 10 is a cleaning liquid supply port (liquid supply) for supplying a cleaning liquid to the measurement tank 101 in the vicinity of the bottom of the measurement tank 101 in the oxidation-reduction potential measuring apparatus described in the first embodiment. A communication port for the pipe 109 is provided. 10 and FIG. 11, the supply port of the reduction water 115 and the supply port of the cleaning liquid are the same, and the supply of the liquid to the communication port of the liquid supply pipe 109 is switched. However, these supply ports can be provided separately.
The reduced water production system 700 is a reduced water generating means (electrolyzer 720, first dissolution module 737, second dissolution module 735, desorption) that obtains reduced water 115 by dissolving hydrogen gas generated by water electrolysis in water. Ion water supply pipe 729, ozone gas supply pipe 731, hydrogen gas supply pipe 733) and switching means (reduction water supply valve 749, ozone water supply) for switching the liquid supplied into the measurement tank 101 from the communication port of the liquid supply pipe 109. And a valve 751).
The liquid is a liquid to be measured and a cleaning liquid. The liquid to be measured is reduced water 115. In addition, the cleaning liquid contains water and ozone gas generated by electrolysis of water in the reduced water generating means.

  Hereinafter, the configuration of the reduced water production system 700 shown in FIG. 10 will be described in more detail. The reduced water production system 700 includes the oxidation-reduction potential measuring device 110 and the electrolysis device 720 shown in FIG.

  The electrolyzer 720 includes an electrolysis tank to which water is supplied from an external water supply source. A pair of electrodes is disposed in the water supplied into the electrolysis tank, and electrolysis is performed by applying a voltage between the electrodes. The obtained hydrogen gas and ozone gas are each dissolved in water to produce reduced water (hydrogen water) and oxidized water (ozone water). Specifically, an electrolysis tank 721, a partition wall 725 that divides the electrolysis tank 721 into two chambers, an anode electrode 723 disposed in one chamber of the electrolysis tank 721, and the other of the electrolysis tank 721. A cathode electrode 727 disposed in the chamber.

Hydrogen (H ₂ ) gas is generated from the chamber in which the cathode electrode 727 is provided. This hydrogen gas reaches the first melting module 737 through the hydrogen gas supply pipe 733 from the chamber in which the cathode electrode 727 is provided. The first dissolution module 737 is supplied with deionized water in a deionized water (DIW) housing (not shown) via a deionized water supply pipe 729. The first dissolution module 737 is a module that generates reduced water 115 by dissolving hydrogen gas in deionized water. The reduced water 115 generated in the first dissolution module 737 is pH adjusted in the first reduced water supply pipe 743 communicating with the first dissolution module 737, and then the reduced water 115 is supplied from the first reduced water supply pipe 743. Supplied to the intended device.

  The first reduced water supply pipe 743 communicates with a diluted ammonia storage section 739 via a diluted ammonia supply pipe 741, and the diluted ammonia storage section 739 stores ammonia for adjusting the pH of the reduced water 115. Yes. The diluted ammonia supply pipe 741 is provided with a diluted ammonia supply valve 753 that adjusts whether or not the diluted ammonia is supplied from the diluted ammonia storage part 739 to the first reduced water supply pipe 743 and the supply amount.

  A part of the reduced water 115 reaches the liquid supply pipe 109 via the second reduced water supply pipe 745 branched from the first reduced water supply pipe 743. The second reduced water supply pipe 745 branches from the first reduced water supply pipe 743 on the downstream side of the junction with the diluted ammonia supply pipe 741, that is, on the side away from the electrolyzer 720. A connecting portion between the liquid supply pipe 109 and the second reducing water supply pipe 745 is provided with a reducing water supply valve 749 for adjusting the supply of the reducing water 115 to the measuring tank 101 of the oxidation-reduction potential measuring device 110. Can do.

On the other hand, ozone (O ₃ ) gas is generated from the chamber in which the anode electrode 723 is provided. The ozone gas reaches the second melting module 735 through the ozone gas supply pipe 731 from the chamber in which the anode electrode 723 electrode is provided. Deionized water in a deionized water storage unit (not shown) is supplied to the second dissolution module 735 via a deionized water supply pipe 729. The second dissolution module 735 is a module that generates ozone water by dissolving ozone gas in deionized water. Ozone water is one type of oxidizing water and is used as a cleaning liquid. The ozone water generated by the second dissolution module 735 reaches the liquid supply pipe 109 via the ozone water supply pipe 747 communicating with the second dissolution module 735. An ozone water supply valve 751 is provided at the connection between the ozone water supply pipe 747 and the liquid supply pipe 109 to adjust whether or not the ozone water is supplied and the supply amount.

  The liquid supply pipe 109 is branched into two, one connected to the second reducing water supply pipe 745 and the other connected to the ozone water supply pipe 747. For this reason, the liquid supplied to the measurement tank 101 can be switched between ozone water and reducing water 115.

  Next, the configuration of the control system of the reduced water production system 700 shown in FIG. 10 will be described. FIG. 11 is a block diagram illustrating a configuration of the reduced water production system 700. As shown in FIG. 11, the reduced water production system 700 has a control unit 755 (not shown in FIG. 10) that controls the operations of the reduced water supply valve 749, the ozone water supply valve 751, and the diluted ammonia supply valve 753. . The control unit 755 has a pH control unit 767 (not shown in FIG. 10) and an ORP control unit 765 (not shown in FIG. 10).

  The pH control unit 767 adjusts the opening and closing of the diluted ammonia supply valve 753 based on the measured value of the pH sensor 763 (not shown in FIG. 10) that measures the pH of the reduced water 115, and supplies the first reduced water supply pipe 743. The presence / absence and amount of ammonia for pH adjustment are controlled. Thereby, the pH of the reduced water 115 is adjusted within a predetermined range. The pH of the reduced water 115 is, for example, 6.5 or more and 14 or less.

  The ORP control unit 765 adjusts the opening and closing of the reducing water supply valve 749 and the ozone water supply valve 751 at regular intervals based on the time information input from the time measuring unit 757 (not shown in FIG. 10), and the liquid The supply of the reducing water 115 and the ozone water from the supply pipe 109 to the measurement tank 101 is controlled. Thereby, in addition to the measurement of the oxidation-reduction potential of the reduced water 115, the working electrode 105 and the reference electrode 107 are cleaned.

Next, the measurement of the oxidation-reduction potential of the reducing water 115 and the electrode cleaning procedure of this embodiment will be described. Also in this embodiment, steps 101 to 104 of the first embodiment are used as basic measurement steps.
Then, after the step of exposing the working electrode 105 and the reference electrode 107 in Step 102 and before the step of contacting the working electrode 105 and the reference electrode 107 in Step 103 again with the reducing water 115, the bottom of the measuring tank 101 is obtained. A step of supplying the cleaning liquid from near the working electrode 105 and contacting the working electrode 105 and the reference electrode 107 with the cleaning liquid, and a step of discharging the cleaning liquid from the vicinity of the bottom of the measuring tank 101.
The step of measuring the oxidation-reduction potential of the reduced water 115 is a step of measuring the oxidation-reduction potential of the reduced water 115 containing hydrogen and water generated by water electrolysis, and the cleaning liquid is electrolyzed by the water. It is a liquid (ozone liquid) containing the generated ozone and water.

  Hereinafter, with reference to FIGS. 10 to 12, the measurement of the oxidation-reduction potential of the reducing water 115 in the measuring tank 101 and the procedure for cleaning the electrodes will be described in more detail. FIG. 12 is a flowchart showing the procedure for measuring the redox potential of the reduced water 115 and cleaning the electrodes.

  First, the ORP control unit 765 opens the reduced water supply valve 749 and closes the ozone water supply valve 751 to supply the reduced water 115 into the measurement tank 101 (S701). As a result, the sensor 103 can measure the redox potential of the reduced water 115. After a predetermined time has elapsed (YES in S702), the ORP control unit 765 closes the reduced water supply valve 749 to stop the supply of reduced water (S703), and the reduced water 115 in the measurement tank 101 is drained from the drain pipe 111. (S704). As a result, the surfaces of the working electrode 105 and the reference electrode 107 are exposed, and the bubbles 119 attached to the surfaces are removed.

  After discharging the reducing water 115 for a predetermined time (YES in S705), the ORP control unit 765 opens the ozone water supply valve 751 and supplies ozone water into the measurement tank 101 (S706). As a result, the working electrode 105 and the reference electrode 107 are immersed in the ozone water, and the electrode surface is cleaned. The cleaning frequency of the sensor 103 is, for example, about once / day. Moreover, the time which makes the working electrode 105 and the reference electrode 107 contact ozone water shall be about 1 to 5 minutes, for example.

  When the predetermined time has elapsed (YES in S707), the ozone water supply valve 751 is closed, and the supply of ozone water is stopped (S708). Then, the ozone water in the measurement tank 101 is discharged from the drain pipe 111 (S709). After the ozone water is drained for a certain time (YES in S710), when the redox potential is measured (YES in S711), the reduced water supply valve 749 is opened and the reduced water is again put into the measurement tank 101. Is supplied (S701).

  In the above procedure, the ORP control unit 765 stops the supply of the reducing water 115 when the measured value of the oxidation-reduction potential in the sensor 103 is outside the predetermined range (S703), and the sensor after step 704 103 may be configured to perform cleaning.

Next, the effect of the reduced water production system 700 shown in FIGS. 10 and 11 will be described.
In the reduced water production system 700, an ozone water supply pipe 747 is connected to the liquid supply pipe 109 so that ozone water can be supplied into the measurement tank 101. For this reason, the working electrode 105 and the reference electrode 107 can be periodically contacted with ozone water. By periodically bringing the working electrode 105 and the reference electrode 107 into contact with ozone water, these electrode surfaces are modified to effectively remove the hydrogen gas adhering to the electrode surfaces or occluded in the platinum electrodes. Can be removed. For this reason, compared with the case of the measurement using only the oxidation-reduction potential measuring device described in the above embodiment, the measured value can be recovered more sufficiently.

  Further, in the reduced water production system 700, ozone gas generated in the chamber provided with the anode electrode 723 of the electrolyzer 720 is dissolved in deionized water by the first dissolution module 737 to produce ozone water, and reduced. By switching the water supply valve 749 and the ozone water supply valve 751, the working electrode 105 and the reference electrode 107 can be periodically cleaned. For this reason, ozone gas generated as a by-product in the electrolyzer 720 for producing the reduced water 115 and discarded can be efficiently used for electrode cleaning. For this reason, the reduced water production system 700 can manage the quality of the reduced water 115 by efficiently using the product in the electrolyzer 720 with a simple configuration of the entire system.

  Further, the control unit 755 has an ORP control unit 765 and a pH control unit 767, and is configured to control pH adjustment of the reducing water 115, measurement of the oxidation-reduction potential of the reducing water 115, and electrode cleaning. For this reason, the pH and redox potential of the reduced water 115 can be adjusted more stably by a simpler method.

  In the above description, the reduced water production system 700 having the redox potential measuring device 110 shown in FIG. 2 has been described as an example. However, the reduced water production system has a configuration having the redox potential measuring device 100 shown in FIG. You can also

  FIG. 13 is a diagram showing a configuration of a reduced water production system having the oxidation-reduction potential measuring device 100. As shown in FIG. The basic configuration of the reduced water production system 710 shown in FIG. 13 is the same as that of the reduced water production system 700 shown in FIG. 10, but the oxidation reduction potential measurement device 100 is provided instead of the oxidation reduction potential measurement device 110. The point is different.

  Specifically, in addition to the configuration shown in FIG. 10, the reduced water production system 710 is further provided in the overflow pipe 113, the second reduced water discharge valve 161 provided in the overflow pipe 113, and the drain pipe 111. And a first reduced water discharge valve 159. The second reducing water discharge valve 161 adjusts whether or not the reducing water 115 is discharged from the measuring tank 101 via the overflow pipe 113 and the amount thereof. The first reducing water discharge valve 159 adjusts whether or not the reducing water 115 is discharged from the measurement tank 101 via the drain pipe 111 and the amount thereof.

  FIG. 14 is a block diagram showing the configuration of the reduced water production system 710 shown in FIG. As shown in FIG. 14, in the reduced water production system 710, the ORP controller 765 has a first reduced water discharge valve 159 and a second reduced water discharge valve in addition to the reduced water supply valve 749 and the ozone water supply valve 751. The opening / closing of 161 is also controlled.

  The redox potential measurement of the reduced water 115 and the cleaning procedure of the sensor 103 in the reduced water production system 710 shown in FIGS. 13 and 14 can be performed according to the procedure shown in FIG.

  In step 701 in FIG. 12, the ORP control unit 765 opens the reduced water supply valve 749 and the second reduced water discharge valve 161 when supplying the reduced water 115, and opens the ozone water supply valve 751 and the first reduced water. The discharge valve 159 is closed. Further, when the reduced water 115 is discharged in step 704, the first reduced water discharge valve 159 is opened, and the reduced water supply valve 749, the ozone water supply valve 751 and the second reduced water discharge valve 161 are closed. To do. In step 706, when supplying ozone water, the ozone water supply valve 751 and the second reduced water discharge valve 161 are opened, and the reduced water supply valve 749 and the first reduced water discharge valve 159 are closed. . When the ozone water is discharged in step 709, the first reduced water discharge valve 159 is opened, and the reduced water supply valve 749, the ozone water supply valve 751 and the second reduced water discharge valve 161 are closed. .

  According to the reduced water production system 710 shown in FIG. 13 and FIG. 14, the water level in the measuring tank 101 is more stably maintained because the redox potential measuring device 100 shown in FIG. 1 is provided as the redox potential measuring device. can do. Therefore, the redox potential measurement of the reduced water 115 can be performed more stably. In addition, since the ORP control unit 765 controls the switching of the drainage from the drain pipe 111 and the overflow pipe 113, the measurement of the oxidation-reduction potential and the cleaning of the electrodes can be performed even in the configuration further including the overflow pipe 113. It is a simple and reliable configuration.

  11 and 14, a single control unit 755 directly controls the operation of each valve. However, a control unit that controls the operation of each valve is provided separately, and these control units are managed. The process management unit may be provided. At this time, the process management unit can be configured to manage the operation of each control unit with reference to the information of the timing unit 757 and the measurement results of the sensor 103 and the pH sensor 763.

  Further, it is more preferable that after the working electrode 105 and the reference electrode 107 are brought into contact with ozone water, before the contact with the reducing water 115 again, the ozone water is replaced with pure water and rinsed. In this case, ozone water adhering to the surface of the sensor 103 can be reliably removed and then brought into contact with the reduced water 115, so that mixing of the ozone water into the reduced water 115 can be suppressed. Therefore, it is possible to suppress a reduction in reducing property of the reducing water 115.

  Next, a redox potential measuring device of a type having a cleaning tank will be described. Also for this type of oxidation-reduction potential measuring device, the basic configuration can be the configuration of the oxidation-reduction potential measuring device described in the above embodiment, for example, the configuration of the oxidation-reduction potential measuring device 100 shown in FIG. A difference is that a cleaning tank is provided adjacent to the measurement tank, and the cleaning liquid is supplied to the cleaning tank.

FIG. 15 is a diagram showing the configuration of such a redox potential measuring apparatus. The oxidation-reduction potential measuring apparatus 800 shown in FIG. 15 is in contact with the measurement tank 801 that stores the liquid to be measured (reduced water 815) to be measured for the oxidation-reduction potential, and the reduced water 815 in the measurement tank 801. And a cleaning tank 825 in which a cleaning liquid 831 for cleaning the working electrode 805 and the reference electrode 807 is accommodated, and a redox potential of the reduced water 815 is measured (the working electrode 805 and the reference electrode 807).
The measurement tank 801 is provided in the vicinity of the bottom of the measurement tank 801, a supply port for supplying the reduced water 815 to the measurement tank 801 (a communication port of the liquid supply pipe 809), and a discharge for discharging the reduced water 815 from the measurement tank 801. It has an outlet (a communication port for the drain pipe 811) and a first electrode attachment portion (measurement tank lid 841) for attaching the working electrode 805 and the reference electrode 807 in the measurement tank 801.
The cleaning tank 825 has a second electrode mounting portion (cleaning tank lid 843) for mounting the working electrode 805 and the reference electrode 807 in the cleaning tank 825.

  More specifically, the oxidation-reduction potential measuring device 800 is reduced to a measurement tank 801, a cleaning tank 825 provided adjacent to the measurement tank 801, a sensor 803 disposed at a predetermined position in the measurement tank 801, and the measurement tank 801. A liquid supply pipe 809 that supplies water 815, a drain pipe 811 that discharges the reduced water 815 from the measurement tank 801, a cleaning liquid supply pipe 827 that supplies the cleaning liquid 831 to the cleaning tank 825, and a cleaning liquid discharge that discharges the cleaning liquid 831 from the cleaning tank 825 It has a tube 829.

  The sensor 803 is a redox potential sensor, and has a working electrode 805 and a reference electrode 807 as electrodes. The sensor 803 can be attached to and detached from, for example, a measurement tank lid 841 that is an upper plate of the measurement tank 801 and a cleaning tank lid 843 that is an upper plate of the cleaning tank 825. By attaching the sensor 803 to any one of these, the working electrode 805 and the reference electrode 807 can be arranged in any of the measurement tank 801 and the cleaning tank 825.

  As the cleaning liquid 831, for example, an acidic liquid such as diluted HCl is used. Further, an oxidizing solution such as ozone water may be used. At this time, for example, ozone generated in the electrolyzer 720 for producing reduced water shown in FIG. 10 can be dissolved in water and supplied to the cleaning tank 825.

  The liquid supply pipe 809 is inserted into the measurement tank 801 from the bottom surface of the measurement tank 801 and communicates with the measurement tank 801. Note that the liquid supply pipe 809 may be provided with a flow rate adjusting member (not shown) such as a valve for adjusting the supply amount of the reducing water 815. The drain pipe 811 is provided on the bottom surface of the measurement tank 801 and communicates with the measurement tank 801.

Next, a method for measuring the redox potential of the reduced water 815 using the redox potential measuring apparatus 800 will be described.
The measurement method of the present embodiment includes the following steps.
Step 801: A step of bringing the electrode (working electrode 805, reference electrode 807) for measuring the oxidation-reduction potential of the liquid to be measured (measurement tank 801) into contact with the reduced water 815 and measuring the oxidation-reduction potential of the reduced water 815,
Step 802: After the step of measuring the oxidation-reduction potential (Step 801), the working electrode 805 and the reference electrode 807 are brought into contact with the cleaning solution 831 for cleaning, and Step 803: The working electrode 805 and the reference electrode 807 are set to the cleaning solution 831. A step of measuring the oxidation-reduction potential of the reduced water 815 by bringing the working electrode 805 and the reference electrode 807 into contact with the reduced water 815 again after the step of cleaning by contact (step 802).

Hereinafter, the oxidation-reduction potential measurement method using the oxidation-reduction potential measuring apparatus 800 will be described in more detail.
First, the sensor 803 is installed in the measurement tank 801, and the reducing water 815 is sent from the liquid supply pipe 809. Then, the redox potential of the reduced water 815 is measured by the sensor 803.

  When a predetermined time has elapsed, the sensor 803 is moved from the measurement tank 801 to the cleaning tank 825. Then, the cleaning liquid 831 is supplied from the cleaning liquid supply pipe 827 into the cleaning tank 825, and the working electrode 805 and the reference electrode 807 of the sensor 803 are brought into contact with the cleaning liquid 831. Note that the reduced water 815 in the measurement tank 801 is discharged from the drain pipe 811, and the reduced water 815 is newly supplied into the measurement tank 801 from the liquid supply pipe 809.

  After the sensor 803 is brought into contact with the cleaning solution 831 for a predetermined time for cleaning, the sensor 803 is returned to the measuring tank 801 and measurement is performed again.

Next, the effect of the oxidation-reduction potential measuring apparatus 800 will be described.
In the oxidation-reduction potential measuring apparatus 800, a measurement tank 801 and a cleaning tank 825 are adjacent to each other, and a cleaning liquid 831 such as an acidic liquid is accommodated in the cleaning tank 825. The sensor 803 is movable and can be arranged in both the measurement tank 801 and the cleaning tank 825. Therefore, the electrode can be cleaned by periodically bringing the working electrode 805 and the reference electrode 807 into contact with the cleaning liquid 831 every time measurement is performed for a predetermined time. Therefore, the bubble 819 can be removed more reliably and measurement can be performed more stably than in the case of measurement using only the oxidation-reduction potential measuring device described in the first embodiment.

  In the oxidation-reduction potential measuring apparatus 800, an overflow pipe provided on the side surface of the measurement tank 801 and communicating with the measurement tank 801 may be provided instead of the drain pipe 811. In this way, when measuring the redox potential of the reduced water 815, excess reduced water 815 can be discharged from the overflow pipe, so that the level of the reduced water 815 can be maintained more stably and measurement can be performed stably. Can do. Further, both the drain pipe 811 and the overflow pipe can be provided.

  Alternatively, the sensor 803 may be fixed to the lid portion and moved between the measurement tank 801 and the cleaning tank 825 together with the lid portion.

  Also in the oxidation-reduction potential measuring apparatus 800, as in the case of the reduced water production system 700 and the reduced water production system 710, the working electrode 805 and the reference electrode 807 are brought into contact with the cleaning solution 831 and then again brought into contact with the reduced water 815. More preferably, the cleaning liquid 831 is replaced with pure water before being rinsed. In this way, since the cleaning liquid 831 attached to the surface of the sensor 803 can be reliably removed and then brought into contact with the reduced water 815, the mixing of ozone water into the reduced water 815 can be suppressed. Therefore, the reducibility of the reduced water 815 can be further ensured.

  As mentioned above, although embodiment of this invention was described with reference to drawings, these are the illustrations of this invention, Various structures other than the above are also employable.

It is sectional drawing which shows the structure of the oxidation reduction potential measuring apparatus in embodiment. It is sectional drawing which shows the structure of the oxidation reduction potential measuring apparatus in embodiment. It is sectional drawing which shows the structure of the oxidation reduction potential measuring apparatus in embodiment. It is sectional drawing which shows the structure of the oxidation reduction potential measuring apparatus in embodiment. It is sectional drawing which shows the structure of the oxidation reduction potential measuring apparatus in embodiment. It is sectional drawing which shows the structure of the oxidation reduction potential measuring apparatus in embodiment. It is sectional drawing which shows the structure of the oxidation reduction potential measuring apparatus in embodiment. It is sectional drawing which shows the structure of the oxidation reduction potential measuring apparatus in embodiment. It is sectional drawing which shows the structure of the oxidation reduction potential measuring apparatus in embodiment. It is a figure which shows the structure of the reduced water manufacturing system in embodiment. It is a block diagram which shows the structure of the reduced water manufacturing system in embodiment. It is a flowchart which shows the procedure of the oxidation-reduction potential measurement in embodiment. It is a figure which shows the structure of the reduced water manufacturing system in embodiment. It is a block diagram which shows the structure of the reduced water manufacturing system in embodiment. It is sectional drawing which shows the structure of the oxidation reduction potential measuring apparatus in embodiment.

Explanation of symbols

100 Redox potential measuring device 101 Measuring tank 103 Sensor 105 Working electrode 107 Reference electrode 109 Liquid supply pipe 110 Redox potential measuring device 111 Drain pipe 113 Overflow pipe 115 Reducing water 117 Liquid surface 119 Bubble 159 First reducing water discharge valve 161 1st Bireduced water discharge valve 200 Redox potential measuring device 201 Measuring tank 203 Sensor 205 Working electrode 207 Reference electrode 209 Liquid supply pipe 210 Redox potential measuring device 211 Drain pipe 213 Overflow pipe 215 Reduced water 217 Liquid surface 219 Bubble 221 Vibration plate 223 Vibration wave 300 Redox potential measuring device 301 Measuring tank 303 Sensor 305 Working electrode 307 Reference electrode 309 Liquid supply pipe 310 Redox potential measuring device 311 Drain pipe 313 Overflow pipe 315 Reduced water 317 Liquid surface 319 Bubble 321 Star Over 323 stirrer 400 redox potential measuring apparatus 401 measuring tank 403 sensor 405 working electrode 407 reference electrode 409 liquid supply pipe 413 overflow pipe 415 reduced water 417 liquid level 419 bubbles 421 inert gas supply pipe 423 N ₂ gas 500 redox potential Measuring device 501 Measuring tank 503 Sensor 505 Working electrode 507 Reference electrode 509 Liquid supply pipe 513 Overflow pipe 515 Reduced water 519 Bubble 521 Flow adjustment valve 523 Pump 600 Oxidation reduction potential measuring device 601 Measuring tank 603 Sensor 605 Working electrode 607 Reference electrode 609 Liquid Supply pipe 613 Overflow pipe 615 Reduced water 617 Liquid level 619 Bubble 621 Cooler 700 Reduced water production system 710 Reduced water production system 720 Electrolysis apparatus 721 Electrolysis tank 723 Anode electrode 725 Bulkhead 727 Casaw Electrode 729 Deionized water supply pipe 731 Ozone gas supply pipe 733 Hydrogen gas supply pipe 735 Second dissolution module 737 First dissolution module 739 Diluted ammonia storage part 741 Diluted ammonia supply pipe 743 First reduced water supply pipe 745 Second reduced water supply pipe 747 Ozone water supply pipe 749 Reduced water supply valve 751 Ozone water supply valve 753 Diluted ammonia supply valve 755 Control unit 757 Timekeeping unit 763 pH sensor 765 ORP control unit 767 pH control unit 800 Oxidation reduction potential measuring device 801 Measurement tank 803 Sensor 805 Action Electrode 807 Reference electrode 809 Liquid supply pipe 811 Drain pipe 815 Reduced water 819 Bubble 825 Cleaning tank 827 Cleaning liquid supply pipe 829 Cleaning liquid discharge pipe 831 Cleaning liquid 841 Measurement tank lid 843 Cleaning tank lid

Claims (20)

A measuring tank for storing a liquid to be measured whose oxidation-reduction potential is to be measured;
An electrode that is disposed so as to be in contact with the liquid to be measured in the measurement tank, and that measures a redox potential of the liquid to be measured;
A supply port that is provided near the bottom of the measurement tank and supplies the liquid to be measured to the measurement tank;
Provided near the bottom of the measurement tank, and a discharge port for discharging the liquid to be measured from the measurement tank;
An oxidation-reduction potential measuring apparatus comprising:   The oxidation-reduction potential measuring device according to claim 1, wherein an excess liquid discharge port for discharging the excess liquid to be measured in the measurement tank is provided above the discharge port, and the electrode is The oxidation-reduction potential measuring device is disposed below the surplus liquid discharge port.   3. The oxidation-reduction potential measuring apparatus according to claim 1, wherein a cleaning liquid supply port for supplying a cleaning liquid to the measurement tank is provided in the vicinity of the bottom of the measurement tank. . In the oxidation-reduction potential measuring device according to claim 3,
Reduced water generating means for obtaining reduced water by dissolving hydrogen gas generated by water electrolysis in water;
Switching means for switching the liquid supplied from the supply port into the measurement tank;
Have
The liquid is the liquid to be measured and the cleaning liquid,
The measured liquid is the reduced water,
The oxidation-reduction potential measuring apparatus, wherein the cleaning liquid contains water and ozone gas generated by electrolysis of the water in the reduced water generating means. A measuring tank for storing a liquid to be measured whose oxidation-reduction potential is to be measured;
An electrode that is disposed so as to be in contact with the liquid to be measured in the measurement tank, and that measures a redox potential of the liquid to be measured;
A supply port that is provided near the bottom of the measurement tank and supplies the liquid to be measured to the measurement tank;
An excess liquid discharge port provided in the measurement tank, for discharging excess liquid to be measured in the measurement tank,
Vibration means for applying vibration to the liquid to be measured in the measurement tank;
Have
The oxidation-reduction potential measuring device, wherein the electrode is disposed below the surplus liquid discharge port. A measuring tank for storing a liquid to be measured whose oxidation-reduction potential is to be measured;
An electrode that is disposed so as to be in contact with the liquid to be measured in the measurement tank, and that measures a redox potential of the liquid to be measured;
A supply port that is provided near the bottom of the measurement tank and supplies the liquid to be measured to the measurement tank;
An excess liquid discharge port provided in the measurement tank, for discharging excess liquid to be measured in the measurement tank,
Stirring means for stirring the liquid to be measured in the measurement tank;
Have
The oxidation-reduction potential measuring device, wherein the electrode is disposed below the surplus liquid discharge port. A measuring tank for storing a liquid to be measured whose oxidation-reduction potential is to be measured;
An electrode that is disposed so as to be in contact with the liquid to be measured in the measurement tank, and that measures a redox potential of the liquid to be measured;
A supply port that is provided near the bottom of the measurement tank and supplies the liquid to be measured to the measurement tank;
An excess liquid discharge port provided in the measurement tank, for discharging excess liquid to be measured in the measurement tank,
In the vicinity of the electrode arranged in the measurement tank, a gas supply unit for introducing an inert gas,
Have
The oxidation-reduction potential measuring device, wherein the electrode is disposed below the surplus liquid discharge port. A measuring tank for storing a liquid to be measured whose oxidation-reduction potential is to be measured;
An electrode that is disposed so as to be in contact with the liquid to be measured in the measurement tank, and that measures a redox potential of the liquid to be measured;
A supply port that is provided near the bottom of the measurement tank and supplies the liquid to be measured to the measurement tank;
An excess liquid discharge port provided in the measurement tank, for discharging excess liquid to be measured in the measurement tank,
A liquid feeding section for feeding the liquid to be measured from the supply port into the measurement tank so that the inside of the measurement tank has a positive pressure with respect to the outside;
Have
The electrode is disposed below the excess liquid discharge port;
An oxidation-reduction potential measuring apparatus, wherein the measuring tank has a sealed structure. A measuring tank for storing a liquid to be measured whose oxidation-reduction potential is to be measured;
An electrode that is disposed so as to be in contact with the liquid to be measured in the measurement tank, and that measures a redox potential of the liquid to be measured;
A supply port that is provided near the bottom of the measurement tank and supplies the liquid to be measured to the measurement tank;
An excess liquid discharge port provided in the measurement tank, for discharging excess liquid to be measured in the measurement tank,
A cooling means for cooling the liquid to be measured;
Have
The oxidation-reduction potential measuring device, wherein the electrode is disposed below the surplus liquid discharge port. A measuring tank for storing a liquid to be measured whose oxidation-reduction potential is to be measured;
An electrode that is disposed so as to be in contact with the liquid to be measured in the measurement tank, and that measures a redox potential of the liquid to be measured;
A cleaning tank containing a cleaning solution for cleaning the electrode;
Have
The measuring tank is
A supply port that is provided near the bottom of the measurement tank and supplies the liquid to be measured to the measurement tank;
A discharge port for discharging the liquid to be measured from the measurement tank;
A first electrode mounting portion for mounting the electrode in the measuring tank;
Have
The washing tank is
An oxidation-reduction potential measuring device having a second electrode mounting portion for mounting the electrode in the cleaning tank. Contacting an electrode for measuring the oxidation-reduction potential of the measurement liquid with the measurement liquid, and measuring the oxidation-reduction potential of the measurement liquid;
After the step of measuring the oxidation-reduction potential, discharging the liquid to be measured from the vicinity of the bottom of the measurement tank and exposing the surface of the electrode;
After the step of exposing the surface of the electrode, supplying a liquid to be measured from the vicinity of the bottom of the measurement tank, and bringing the electrode into contact with the liquid to be measured again;
A method for measuring an oxidation-reduction potential, comprising:   The method for measuring the oxidation-reduction potential according to claim 11, wherein the step of measuring the oxidation-reduction potential of the liquid to be measured is above the position where the electrode is installed while supplying the liquid to be measured into the measurement tank. And measuring the oxidation-reduction potential of the liquid to be measured while allowing excess liquid to be measured to flow over and discharging. The method for measuring a redox potential according to claim 11 or 12, wherein after the step of exposing the surface of the electrode, before the step of bringing the electrode into contact with the liquid to be measured again,
Supplying a cleaning liquid from the vicinity of the bottom of the measuring tank, and bringing the electrode into contact with the cleaning liquid;
Discharging the cleaning liquid from the vicinity of the bottom of the measuring tank;
A method for measuring an oxidation-reduction potential, comprising: The method for measuring a redox potential according to claim 13,
The step of measuring the oxidation-reduction potential of the liquid to be measured is a step of measuring the oxidation-reduction potential of reduced water containing hydrogen and water generated by water electrolysis,
The method for measuring an oxidation-reduction potential, wherein the cleaning liquid is a liquid containing ozone and water generated by electrolysis of the water.   An oxidation reduction characterized by measuring an oxidation-reduction potential of the measurement liquid while vibrating the measurement liquid while an electrode for measuring the oxidation-reduction potential of the measurement liquid is in contact with the measurement liquid. Measuring method of potential.   An oxidation reduction characterized by measuring an oxidation-reduction potential of the measurement liquid while stirring the measurement liquid in a state where an electrode for measuring the oxidation-reduction potential of the measurement liquid is in contact with the measurement liquid. Measuring method of potential.   Oxidation characterized in that an electrode for measuring a redox potential of a liquid to be measured is brought into contact with the liquid to be measured and an oxidation-reduction potential of the liquid to be measured is measured while introducing an inert gas in the vicinity of the electrode. Method for measuring reduction potential.   The electrode for measuring the oxidation-reduction potential of the liquid to be measured is in contact with the liquid to be measured in a sealed measuring tank, and the inside of the measuring tank is set to a positive pressure from the outside of the measuring tank. A method for measuring a redox potential, comprising measuring a redox potential of a liquid.   An oxidation-reduction potential characterized by measuring an oxidation-reduction potential of the measurement liquid by bringing an electrode for measuring the oxidation-reduction potential of the measurement liquid into contact with the measurement liquid in a state where the measurement liquid is cooled. Measuring method. Contacting an electrode for measuring the oxidation-reduction potential of the measurement liquid with the measurement liquid, and measuring the oxidation-reduction potential of the measurement liquid;
After the step of measuring the oxidation-reduction potential, the step of cleaning the electrode in contact with a cleaning solution;
After the step of bringing the electrode into contact with the cleaning liquid and cleaning, the step of bringing the electrode into contact with the liquid to be measured again and measuring the oxidation-reduction potential of the liquid to be measured;
A method for measuring an oxidation-reduction potential, comprising:

Images