JP2016135459A - Functional water generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a functional water generator that can detect a decrease in ion adsorption-desorption efficiency and can efficiently treat the adsorption-desorption of ions according to the amount of ions in an aqueous solution and the amount of ions adsorbed by an ion adsorption electrode.SOLUTION: A displacement point determination part (20a) is provided which determines a displacement point where the rate of change of electric conductivity of an aqueous solution in an adsorption step of applying a voltage between an ion adsorption electrode (1) and a counter electrode (2) by voltage application means (E, SW1, SW2) to adsorb ions in the aqueous solution by the ion adsorption electrode (1), or in a desorption step of desorbing the ions from the ion adsorption electrode (1) into the aqueous solution.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a functional water generator, and more particularly to a functional water generator using an ion adsorption electrode.

  Conventionally, as a functional water generating apparatus, there is an apparatus in which two electrodes are arranged with an ion-permeable diaphragm interposed therebetween, and salt water is electrolyzed to prepare acidic water and alkaline water (for example, Patent 3291504 (Patent Reference 1)). This functional water generator forms a laminar flow of alkaline water and a laminar flow of acidic water by electrolyzing the water flowing between the electrodes, and obtains alkaline water and acidic water by taking them out separately. .

Japanese Patent No. 3291504

  However, the above-described conventional functional water generating apparatus generates accurate functional water using a pH meter, and does not efficiently generate functional water. In addition, since the conventional functional water generation device performs the oxygen gas and hydrogen ion generation reaction at the anode and the hydrogen gas and hydroxide ion generation reaction at the cathode at the same time, expensive platinum or the like is used for both the anode and the cathode. The electrode covered with was used. In addition, the above-described conventional functional water generating device has a problem that the salt concentration of the aqueous solution whose pH is adjusted using an ion-permeable diaphragm is high and the device itself is easily corroded.

  In view of this, a functional water generating apparatus that adjusts pH and the like by adsorbing and desorbing ions in an aqueous solution with an ion adsorption electrode using an electric double layer theory has been proposed. This functional water generating device cannot efficiently handle ion adsorption when the number of ions in the aqueous solution decreases during ion adsorption, or ion desorption efficiency when the number of ions adsorbed on the ion adsorption electrode during ion desorption decreases. There is a problem that it cannot be processed well.

  Therefore, the problem of the present invention is to detect a decrease in the adsorption / desorption efficiency of ions, and functional water that can efficiently handle the adsorption / desorption of ions according to the amount of ions in the aqueous solution and the amount of ions adsorbed by the ion adsorption electrode. It is to provide a generation device.

In order to solve the above problems, the functional water generator of the present invention is
A container for containing an aqueous solution;
An ion adsorption electrode disposed in the container and capable of adsorbing and desorbing ions in the aqueous solution;
A counter electrode disposed in the container so as to face the ion-adsorbing electrode with a space therebetween;
Voltage application means for applying a voltage between the ion adsorption electrode and the counter electrode;
The voltage application means applies a voltage between the ion adsorption electrode and the counter electrode to adsorb ions in the aqueous solution to the ion adsorption electrode, or removes ions from the ion adsorption electrode into the aqueous solution. In the desorption step of separating, a change point determination unit for determining a change point at which the change rate of the conductivity of the aqueous solution changes is provided.

Moreover, in the functional water generator of one embodiment,
The change point is a change point at which the conductivity of the aqueous solution changes nonlinearly after a linear change period in which the conductivity of the aqueous solution changes linearly.

Moreover, in the functional water generator of one embodiment,
A conductivity calculator that calculates the conductivity of the aqueous solution based on the voltage applied between the ion adsorption electrode and the counter electrode and the current flowing between the ion adsorption electrode and the counter electrode;
The change point determination unit determines a change point at which the conductivity changes nonlinearly based on the conductivity of the aqueous solution calculated by the conductivity calculation unit.

Moreover, in the functional water generator of one embodiment,
A starting point determination unit that determines a starting point at which a linear change period in which the conductivity of the aqueous solution linearly changes after a voltage is applied between the ion adsorption electrode and the counter electrode is provided.

Moreover, in the functional water generator of one embodiment,
The voltage applying means is a constant current source,
The change point determination unit is a change point in which the conductivity of the aqueous solution changes in a nonlinear manner at a change point in which the voltage changes in a nonlinear manner after a linear change period in which the voltage applied between the ion adsorption electrode and the counter electrode changes in a linear manner. Let it be a point.

Moreover, in the functional water generator of one embodiment,
In an adsorption step of adsorbing ions in the aqueous solution to the ion adsorption electrode by applying a voltage between the ion adsorption electrode and the counter electrode by the voltage application means, between the ion adsorption electrode and the counter electrode. An ion amount calculation unit is provided that calculates the amount of ions adsorbed from the aqueous solution to the ion adsorption electrode based on the amount of current flowing.

  As is clear from the above, according to the present invention, an adsorption step (or from an ion adsorption electrode) in which a voltage is applied between the ion adsorption electrode and the counter electrode by voltage application means to adsorb ions in an aqueous solution to the ion adsorption electrode. In the desorption step in which ions are desorbed from the aqueous solution), the change point determination unit determines the change point at which the conductivity changes nonlinearly after the linear change period during which the conductivity of the aqueous solution changes linearly. It is possible to realize a functional water generating apparatus that can detect a decrease in desorption efficiency and can efficiently handle the adsorption and desorption of ions according to the amount of ions in the aqueous solution and the amount of ions adsorbed by the ion adsorption electrode.

FIG. 1 is a diagram showing a basic configuration of a functional water generator according to a first embodiment of the present invention. FIG. 2 is a diagram showing changes in the amount of adsorbed ions by tap water and saline having different ion concentrations. FIG. 3 is a diagram showing a change in conductivity during the adsorption and desorption of positive ions. FIG. 4 is a diagram showing a change in conductivity during the adsorption and desorption of negative ions. FIG. 5 is a diagram showing a basic configuration of the functional water generating apparatus according to the second embodiment of the present invention. FIG. 6 is a block diagram showing a basic configuration of a functional water generation system using the functional water generation apparatus according to the third embodiment of the present invention. FIG. 7: is a block diagram which shows the basic composition of the functional water production | generation system using the functional water production | generation apparatus of 4th Embodiment of this invention.

  Hereinafter, the functional water generating apparatus of the present invention will be described in detail with reference to the illustrated embodiments.

[First Embodiment]
FIG. 1 shows a basic configuration of a functional water generator according to a first embodiment of the present invention.

  As shown in FIG. 1, the functional water generating apparatus according to the first embodiment includes a treatment tank 10 as an example of a container in which an aqueous solution is stored, an ion adsorption electrode 1 disposed in the treatment tank 10, and a treatment tank. 10, a counter electrode 2 disposed so as to face the ion adsorption electrode 1 with a gap, a DC power source E for applying a DC voltage between the ion adsorption electrode 1 and the counter electrode 2, and an aqueous solution in the treatment tank 10. And a conductivity meter 11 for detecting the conductivity. Here, the DC power source E is a constant current source or a constant voltage source.

  The ion-adsorbing electrode 1 is made of a porous carbon material (for example, activated carbon), and the counter electrode 2 may be an electrode member that does not dissolve, and may be carbon or the like, but a metal that easily undergoes electrolysis of water (for example, Pt, At least one metal (or alloy) of Au, Pd, Rh, and Ir is suitable. For example, the surface of an electrode made of Ti may be coated with Pt. Further, in this embodiment, the ion adsorption electrode 1 and the counter electrode 2 are formed in a flat plate shape, but may be appropriately set according to the electrode material and the shape of the container.

  In the functional water generator, the positive electrode side of the DC power supply E is connected to the ion adsorption electrode 1 and the counter electrode 2 via the changeover switch SW1, and the negative electrode side of the DC power supply E is connected to the ion adsorption electrode 1 via the changeover switch SW2. 2 is connected. By switching the changeover switches SW1 and SW2, the ion adsorption electrode 1 and the counter electrode 2 are arranged so that the ion adsorption electrode 1 becomes an anode (or cathode) and the counter electrode 2 becomes a cathode (or anode). A voltage is applied between them. The DC power supply E and the changeover switches SW1 and SW2 constitute voltage application means.

  The functional water generating apparatus includes a control device 20 including a microcomputer and an input / output circuit. The control device 20 performs functional water generation processing by controlling the changeover switches SW1 and SW2 based on the conductivity of the aqueous solution detected by the conductivity meter 11.

  In addition, the control device 20 includes a change point determination unit 20a that determines a change point at which the conductivity of the aqueous solution changes nonlinearly after a linear change period in which the conductivity of the aqueous solution in the treatment tank 10 changes linearly, and the ion adsorption electrode 1 A start point determination unit 20b is provided that determines a start point at which a linear change period in which the conductivity of the aqueous solution changes linearly after a voltage is applied between the counter electrode 2 and the counter electrode 2 is applied. Here, the linear change period in which the conductivity changes linearly is a period in which the change rate of the conductivity (change per unit time) is substantially constant.

  The functional water generating apparatus capable of controlling the ion concentration in an aqueous solution to which the present invention is applied, forms ions in the aqueous solution by forming an electric double layer capacitor between the surface of the ion adsorption electrode 1 and the ions. By adsorbing on the surface of the ion adsorption electrode 1, ions corresponding to the amount of adsorbed ions are reduced from the aqueous solution. In addition, this functional water generating apparatus releases ions adsorbed on the ion adsorption electrode 1 into the aqueous solution by eliminating the formation of the electric double layer capacitor between the surface of the ion adsorption electrode 1 and the ions. It is possible to increase the amount of ions.

  In this functional water generating device, when the electric double layer capacitor is formed, the charge at the time of capacitor formation is created by polarization inside the ion adsorption electrode 1, but the reverse charge is also generated by this polarization. Since this reverse charge flows between the electrodes as a processing current, in this functional water generating apparatus, the installed electrodes are configured as a cathode electrode or an anode electrode. For this reason, one of these electrodes is composed of an electrode capable of adsorbing and desorbing ions. However, when ions are adsorbed and desorbed, it is necessary to reverse the polarity of the electrodes. Changes the polarity of the voltage applied between the electrodes. Table 1 shows the polarity of ions (positive ions and negative ions) and the state of the ion-adsorbing electrode 1 (cathode or anode) due to adsorption / desorption of ions.

  As shown in Table 1 above, it is necessary to reverse the polarity of the ion-adsorbing electrode 1 during adsorption and desorption of ions. Moreover, even if it is the same adsorption | suction process by the charge of the ion to process, the polarity of the ion adsorption electrode 1 will be reversed. For this reason, which electrode is used as a cathode is selected depending on the content to be processed and the charge of ions, and a circuit (including SW1 and SW2) that optimally selects a processing voltage to be applied is required.

  Ions adsorbed on the ion adsorption electrode 1 move between the electrodes according to the voltage applied between the electrodes, and form an electric double layer in the vicinity of the ion adsorption electrode 1. For this reason, when there are sufficient ions in the aqueous solution, there are many ions around the ion-adsorbing electrode 1, so that the electric double layer is efficiently formed. At this time, since the energy for forming the electric double layer is smaller than the electrolysis energy of water, the formation of the electric double layer is preferentially performed with respect to the treatment current.

  As the amount of ions around the ion adsorption electrode 1 decreases, the amount of electric double layer formed also decreases. For this reason, the amount of current consumed in forming the electric double layer is reduced with respect to the amount of current flowing between the electrodes.

  In constant current control in which a constant current is passed between the electrodes that are consumed by the formation of the electric double layer for such an amount of current, the reduced amount of current is consumed by water electrolysis, so that the ion adsorption efficiency Will decline. In addition, even in constant voltage control where a constant voltage is applied between the electrodes, the conductivity of the aqueous solution changes in proportion to the pH change due to ion adsorption. Efficiency is reduced. For this reason, the processing time with good power efficiency varies depending on the ion concentration in the aqueous solution.

  In conventional functional water generators, in order to keep the specifications such as the pH value of the functional water to be generated constant, if the ion concentration is above a certain level in the untreated aqueous solution, the amount of fluctuation such as pH from neutrality is Since it is correlated with the amount of adsorbed ions, processing is performed by constant voltage control or constant current control so that the processing voltage or processing current is constant.

  For this reason, if the ion concentration in the aqueous solution is high, it is possible to perform the ion adsorption / desorption treatment in a state where the treatment efficiency is still good even if the aqueous solution has been subjected to the ion adsorption / desorption treatment. Also, if the ion concentration in the aqueous solution is low, the treated aqueous solution cannot be treated as functional water with the specified ion concentration, so that the functional water generated by installing a pH meter will have the target ion concentration. Some have performed processing while detecting the ion concentration at the time of generating functional water by adjusting the voltage, current, or flow rate.

  The object of the present invention is not to measure the ion concentration of the functional water that is finally required, but to provide a functional water generating device that performs ion adsorption / desorption treatment in a power efficient state.

  In the generation of functional water, changes in pH and conductivity correlate with the ion concentrations of hydrogen ions and hydroxide ions, and the pH decreases as the hydrogen ion concentration increases from neutral (the hydroxide ion concentration decreases). However, while the conductivity increases, the pH and conductivity increase when the hydroxide ion concentration increases from neutrality (hydrogen ion concentration decreases).

  Here, the conductivity is proportional to the amount of ions (however, the conductivity increases in any direction from pH 7), and the variation in conductivity depends on the ion mobility. The greater the amount, the greater the variation in conductivity.

  Also, in ion adsorption / desorption using an electric double layer, the amount of hydrogen ions increases / decreases for positive ions and the amount of hydroxide ions increases / decreases for negative ions according to the charge polarity and valence of the adsorbed / desorbed ions. To do.

  When monovalent ions are adsorbed and desorbed at the ion-adsorbing electrode 1, electrons are exchanged by the polarity of the adsorbed ions at the counter electrode 2, and one of the following reactions occurs.

In the counter electrode 2 when positive ions are adsorbed on the ion adsorption electrode 1,
OH ⁻ → 1/2 H ₂ O + 1/4 O ₂ + e ⁻ (1)
1/2 H ₂ O → H ⁺ + 1/4 O ₂ + e ⁻ (1) ′
In the counter electrode 2 when negative ions are adsorbed on the ion adsorption electrode 1,
H ⁺ + e ⁻ → 1/2 H ₂ (2)
1/2 H ₂ O + e ⁻ → 1/2 H ₂ + OH ⁻ (2) ′
It becomes.

For example, when divalent positive ions are adsorbed on the ion adsorption electrode 1, a capacitor is formed by charges corresponding to the bivalent amount corresponding to the charge amount of the positive ions due to polarization inside the ion adsorption electrode 1. The charge remaining at this time flows as a processing current. This processing current is generated by electrolysis of water at the counter electrode 2. At this time, since oxygen (O ₂ ) is generated, hydroxide ions (OH ⁻ ) are consumed, but hydrogen ions (H ⁺ ) are generated. When one hydroxide ion (OH ⁻ ) is consumed, one electron is generated, so that two hydrogen ions (H ⁺ ) are generated with respect to the treatment current for two valences.

On the other hand, in the case of negative ions, hydrogen ions (H ⁺ ) are consumed and hydroxide ions (OH ⁻ ) are generated. When one hydrogen ion (H ⁺ ) is consumed, one electron is required. Therefore, hydroxide ions (OH ⁻ ) are generated according to the charge amount of the processing current.

For this reason, the amount of hydrogen ions (H ⁺ ) increases or decreases in the case of positive ions, and the amount of hydroxide ions (OH ⁻ ) increases or decreases in the case of negative ions, depending on the charge polarity and valence number of adsorbed and desorbed ions. Even in the case of ion desorption, the electrolysis reaction of water at the counter electrode 2 is different from that in the case of adsorption, but the amount of charge and the amount of hydrogen ions (H ⁺ ) or hydroxide ions (OH ⁻ ) produced are the same charge. Since it is a quantity, the same increase / decrease occurs. For this reason, the electrical conductivity has a correlation with the amount of charge / desorption to the ion adsorption electrode 1 of positive ions and negative ions.

  Here, when sufficient ions are present in the aqueous solution to be treated, the amount of ions adsorbed to and desorbed from the ion adsorption electrode 1 is proportional to the treatment current. For this reason, the amount of ions in the aqueous solution is uniformly increased or decreased according to the state of ion adsorption / desorption. However, since the amount of ions in the aqueous solution or the amount of ions adsorbed on the ion adsorption electrode 1 is finite, if a certain amount of ion adsorption / desorption treatment is continuously performed, ions necessary for the treatment are insufficient. It becomes the situation to do. In such a situation where ions are insufficient, the amount of ion adsorption / desorption decreases as in the tap water shown in FIG.

  Fig. 2 shows changes in the amount of adsorbed ions by tap water (black diamond ◆) and saline (black square ■) with different ion concentrations. In Fig. 2, the horizontal axis represents the treatment time [minutes], and the vertical axis represents the ions. The amount of adsorption [mol] is expressed.

  The processing conditions in FIG. 2 are as follows.

Capacity of tap water: 80mL (hardness 50mg / L)
Saline capacity: 80 mL (concentration 0.01 mol / L, salt dissolved in the above tap water)
Constant current control: 90 mA, 18 mm distance between electrodes
Activated carbon electrode: Activated carbon electrode sheet (manufactured by Kansai Thermochemical: MSP-20, weight content 92%, 50 × 50 × 0.45 mm)
In FIG. 2, since the salt solution has a sufficient amount of ions, the change point does not appear, whereas the tap water is nonlinear after the ion adsorption amount changes linearly in a treatment time of 1 to 3 minutes. A changing point of change appears.

  For this reason, it is possible to determine whether or not the adsorption / desorption treatment of ions in the aqueous solution is performed efficiently by detecting the change point of the ion adsorption amount.

During actual ion adsorption / desorption, ions that change the characteristics of water are other than hydrogen ions (H ⁺ ) and hydroxide ions (OH ⁻ ). This is because, in the adsorption / desorption of these hydrogen ions and hydroxide ions, the same ions are generated on the counter electrode 2 side, so that the change due to adsorption / desorption appears to be in an equilibrium state. For this reason, if the ion adsorption / desorption process proceeds to some extent, the composition ratio of hydrogen ions or hydroxide ions in the polarity ions gradually increases depending on the polarity of ions to be adsorbed / desorbed. It tends to decrease gradually. Compared to the change in conductivity when the amount of ions in the aqueous solution is consumed, the change rate of conductivity due to hydrogen ions and hydroxide ions is small, and this change makes the change point of conductivity invisible. There is no.

In addition, in the process of adsorbing and desorbing ions in an aqueous solution, the ion mobility of hydrogen ions (H ⁺ ) is much higher than that of other ions in the process of adsorbing positive ions. Since the adsorption of hydrogen ions is given priority, the adsorption of other positive ions is performed after the adsorption of hydrogen ions around the ion adsorption electrode 1 is performed to some extent. For this reason, a period in which the fluctuation of the conductivity is very small can be formed, so that the ion adsorption / desorption is efficiently performed by detecting the changing point where the conductivity changes nonlinearly except the period of the equilibrium state of the conductivity. Can be performed more accurately. Since this equilibrium period exists at the time of adsorption of positive ions shown in FIG. 3 and at the time of desorption of negative ions shown in FIG. 4, in this case, in the determination of the change point at which the conductivity changes nonlinearly, It is necessary to exclude the equilibrium period.

  In addition to the above, other factors that cause nonlinear changes in the conductivity may include a buffering action caused by carbonate ions contained in the solution and an influence caused by chloride ions contained in the solution. In the case of buffering action by carbonate ions, since the ions in water decrease due to the combination of hydrogen ions and carbonate ions, the increase or decrease in conductivity due to the increase in ions does not derive, so the conductivity changes nonlinearly. Cause. In addition, since chloride ions in the solution have a lower ionization tendency than hydroxide ions, chlorine gas is generated prior to the hydroxide ions when the solution is electrolyzed. When chlorine gas is dissolved in the solution, it is separated into hypochlorous acid and hydrochloric acid by pH. In this case, since the pH does not change greatly due to the buffering action, the rate of increase of ions in the solution is also increased by hydroxide ions. Since it is smaller than that in the case of electrolysis and the variation in conductivity is also small, the conductivity similarly causes a nonlinear change.

  The processing conditions of FIGS. 3 and 4 are as follows.

Capacity of tap water: 80mL (hardness 50mg / L)
Constant current control: 90 mA, 18 mm distance between electrodes
Activated carbon electrode: Activated carbon electrode sheet (manufactured by Kansai Thermochemical: MSP-20, weight content 92%, 50 × 50 × 0.45 mm)
In FIG. 3, the linear change period T1 of conductivity at the time of adsorption of positive ions indicated by a dotted line is between the processing time of 2 minutes and 4 minutes. Moreover, in FIG. 4, the linear change period T2 of the electric conductivity at the time of adsorption | suction of the negative ion shown as a continuous line is between process time 2 minutes-5 minutes.

  According to the functional water generating apparatus having the above configuration, an adsorption step (or ion adsorption) in which ions in an aqueous solution are adsorbed to the ion adsorption electrode 1 by applying a voltage between the ion adsorption electrode 1 and the counter electrode 2 by the DC power source E. In the desorption step of desorbing ions from the electrode 1 into the aqueous solution), the change point determination unit 20a determines a change point at which the change rate of the conductivity of the aqueous solution changes, thereby detecting a decrease in ion adsorption / desorption efficiency. . Therefore, when the ion adsorption / desorption efficiency starts to decrease, the ion adsorption / desorption is terminated, so that current does not continue to flow between the electrodes in a state where the ion adsorption / desorption efficiency is deteriorated. Ion adsorption / desorption can be efficiently processed according to the amount of ions adsorbed by the ion adsorption electrode.

  In the adsorption step (or desorption step), the change point determination unit 20a determines a change point at which the conductivity of the aqueous solution changes nonlinearly after a linear change period in which the conductivity of the aqueous solution changes linearly. It is possible to reliably detect a decrease in the adsorption / desorption efficiency.

  In addition, when the DC power source E is a constant current source, positive ions are applied to the ion adsorption electrode 1 after the voltage is applied between the ion adsorption electrode 1 and the counter electrode 2 until the conductivity of the aqueous solution changes linearly. When the negative electrode is adsorbed and when negative ions are desorbed from the ion-adsorbing electrode 1, there is a period in which the variation in conductivity is very small. To do. During this period, the change point determination unit 20a does not determine the change point of the conductivity of the aqueous solution, so that the point at which the conductivity of the aqueous solution changes from linear to nonlinear can be accurately determined.

  In the first embodiment, the conductivity meter 11 that detects conductivity is used. However, a pH meter that detects pH having a correlation with the conductivity may be used. In this case, the change in conductivity may be obtained based on the pH of the aqueous solution detected by the pH meter, and the change point at which the conductivity changes nonlinearly may be determined by the change point determination unit.

  In addition, since the transition of the change in conductivity in time series varies depending on the ion polarity for ion adsorption / desorption, it is possible to optimize the determination method according to the ion to be processed and perform accurate ion adsorption / desorption treatment it can.

  In particular, when the constant current control is performed by the voltage application means, it is possible to identify the conductivity by the applied voltage without providing a conductivity meter. There is no need to do it.

  Furthermore, normally, it is not possible to adsorb more than the amount of ions in the aqueous solution, but if the ions are adsorbed to the ion adsorption electrode a plurality of times, ions larger than the amount of ions in the aqueous solution can be adsorbed. However, since the amount of ions in the aqueous solution is not constant depending on the location, it is not possible to determine the optimum control of the applied voltage, and it is possible to perform adsorption multiple times under optimum adsorption conditions. Further, even if the ion adsorption treatment to the ion adsorption electrode is performed alone, the treatment conditions can be optimized and the treatment for efficiently removing ions from the aqueous solution can be easily realized.

[Second Embodiment]
Next, a functional water generating apparatus according to a second embodiment of the present invention will be described. In the functional water generator of the first embodiment, the change point at which the conductivity changes nonlinearly using the conductivity meter is determined. However, in the functional water generator of the second embodiment, the conductivity meter is not used. A change point where the conductivity changes nonlinearly is detected.

  When sufficient ions are present in the aqueous solution to be treated, the amount of ion adsorption adsorbed on the ion adsorption electrode 1 is proportional to the amount of treatment current. However, when the treatment current amount is set to a value exceeding the ion adsorption amount, the treatment current amount cannot be ensured only by ion adsorption. As a result, a shortage of electrons is generated and consumed, and a shortage of processing current is generated. For this reason, the processing current and the amount of ion adsorption have the following relationship.

(Ion adsorption treatment current) + (Water electrolysis current) = Treatment current (3)
In the relationship of the above formula (3), when the ion concentration in the aqueous solution is sufficiently high, the term of water electrolysis current is such that oxygen (O ₂ ) and hydrogen (H ₂ ) are in the composition ratio of water at both electrodes. Since it is generated in proportion, it becomes a constant term that does not increase or decrease the ion concentration. The term of the ion adsorption treatment current includes an ion adsorption treatment current other than hydrogen ions (H ⁺ ) or hydroxide ions (OH ⁻ ) whose ion concentration varies due to ion adsorption, and hydrogen ions (H ⁺ ) or ion ions whose concentration does not vary. Since it is composed of an ion adsorption treatment current with hydroxide ions (OH ⁻ ), the above equation (3) becomes the following equation (4).

(Ion adsorption treatment current related to ion concentration fluctuation)
+ (Ion adsorption treatment current not related to ion concentration fluctuation)
+ (Water electrolysis current) = Treatment current …… (4)
Since the term which does not participate in the fluctuation | variation of ion concentration among said Formula (4) can be assumed to be a constant term, this Formula (4) can be identified to following Formula (5).

Ion adsorption treatment current related to ion concentration fluctuation = fluctuation of treatment current ...... (5)
For this reason, the ion concentration variation can be detected as a variation in the processing current amount. Moreover, when the ion concentration varies, the conductivity of the aqueous solution also varies. Since the rate of this change is constant, it is possible to detect variations in ion concentration even with variations in the processing voltage obtained from the conductivity of the aqueous solution and the processing current.

  Next, a case where the DC power source E is a constant current source will be described.

  FIG. 5 shows a basic configuration of a functional water generator of the second embodiment of the present invention. The functional water generator of the second embodiment includes a voltmeter and an ammeter instead of the conductivity meter. Except for the operation of the control device, the functional water generating device of the first embodiment has the same configuration, and the same components are denoted by the same reference numerals.

  As shown in FIG. 5, the functional water generating apparatus according to the first embodiment includes a treatment tank 10 as an example of a container in which an aqueous solution is accommodated, an ion adsorption electrode 1 disposed in the treatment tank 10, and a treatment tank. 10, a counter electrode 2 disposed to face the ion adsorption electrode 1 with a space therebetween, a DC power source E that applies a DC voltage between the ion adsorption electrode 1 and the counter electrode 2, and an ion adsorption from the DC power source E A voltmeter 21 for detecting a voltage applied between the electrode 1 and the counter electrode 2 and an ammeter 22 for detecting a processing current flowing between the ion adsorption electrode 1 and the counter electrode 2 are provided. Here, when the DC power source E is a constant current source, the ammeter 22 may not be provided, and when the DC power source E is a constant voltage source, the voltmeter 21 may not be provided.

  In the functional water generator, the positive electrode side of the DC power supply E is connected to the ion adsorption electrode 1 and the counter electrode 2 via the changeover switch SW1, and the negative electrode side of the DC power supply E is connected to the ion adsorption electrode 1 via the changeover switch SW2. 2 is connected. By switching the changeover switches SW1 and SW2, the ion adsorption electrode 1 and the counter electrode 2 are arranged so that the ion adsorption electrode 1 becomes an anode (or cathode) and the counter electrode 2 becomes a cathode (or anode). A voltage is applied between them. The DC power supply E and the changeover switches SW1 and SW2 constitute voltage application means.

  In addition, the functional water generator includes a control device 30 including a microcomputer and an input / output circuit. The control device 30 performs functional water generation processing by controlling the changeover switches SW1 and SW2 based on the output voltage of the DC power source E detected by the voltmeter 21 and the processing current detected by the ammeter 22.

  In addition, the control device 30 includes a conductivity calculating unit 30a that calculates the conductivity of the aqueous solution based on the amount of current flowing between the ion adsorption electrode 1 and the counter electrode 2, and the conductivity of the aqueous solution in the treatment tank 10 is linear. The conductivity of the aqueous solution changes linearly after a voltage is applied between the change point determination unit 30b that determines a change point where the conductivity changes nonlinearly after the changing linear change period and the ion adsorption electrode 1 and the counter electrode 2. It has a start point determination unit 30c that determines a start point at which the linear change period starts, and an ion amount calculation unit 30d that calculates the amount of ions adsorbed on the ion adsorption electrode 1.

  By using the DC power source E as a constant current source, if sufficient ions are present in the aqueous solution, constant ion adsorption / desorption is performed for a constant processing current. At this time, the ion concentration in the aqueous solution fluctuates due to ion adsorption / desorption, so that the electric conductivity of the aqueous solution fluctuates. Therefore, the applied voltage from the DC power source E of the constant current source shows the same behavior as the fluctuation of the electric conductivity of the aqueous solution. It will be. For this reason, in the constant current control, it is possible to detect a change in conductivity based on a change in applied voltage.

  According to the functional water generating apparatus having the above-described configuration, in the adsorption process for adsorbing ions in the aqueous solution to the ion adsorption electrode 1 (or the desorption process for desorbing ions from the ion adsorption electrode 1 into the aqueous solution), the conductivity of the aqueous solution By determining the change point at which the conductivity changes nonlinearly after the linear change period during which the ion changes linearly by the change point determination unit 30b, the ion adsorption / desorption ends when the ion adsorption / desorption efficiency starts to decrease, Thus, the current does not continue to flow between the electrodes in a state in which the adsorption / desorption efficiency of the electrode deteriorates, and the adsorption / desorption of ions can be efficiently processed.

  In addition, since the conductivity of the aqueous solution has a correlation with the amount of charge / desorption to the ion adsorption electrode 1 of positive ions or negative ions, the voltage applied between the ion adsorption electrode 1 and the counter electrode 2 by the DC power source E. And based on the electric current which flows between the ion adsorption electrode 1 and the counter electrode 2, the electrical conductivity of aqueous solution can be easily calculated by the electrical conductivity calculation part 30a.

  Further, the start point determination unit 30c determines the start point of the linear change period in which the conductivity of the aqueous solution changes linearly, and determines the change point at which the conductivity of the aqueous solution changes nonlinearly between the voltage application and the start point. Is not performed by the change point determination unit 30b, the change point of the conductivity of the aqueous solution can be accurately determined.

  In addition, by performing constant current control in which a constant processing current is passed between the ion adsorption electrode 1 and the counter electrode 2, if sufficient ions are present in the aqueous solution, constant ion adsorption / desorption is performed with respect to the processing current. Since the ion concentration in the aqueous solution fluctuates due to ion adsorption / desorption without changing the treatment current, and the conductivity of the aqueous solution fluctuates, the voltage applied between the ion adsorbing electrode 1 and the counter electrode 2 has the electric conductivity. It shows the same behavior as fluctuation. Thereby, in constant current control, it becomes possible to detect the fluctuation | variation of electrical conductivity based on the fluctuation | variation of an applied voltage, and the change point determination part 30b is the voltage applied between the ion adsorption electrode 1 and the counter electrode 2. A change point at which the voltage changes nonlinearly after a linear change period in which the change is linear is taken as a change point of conductivity. Therefore, based on the voltage applied between the ion adsorption electrode 1 and the counter electrode 2, the change point when the electrical conductivity of the aqueous solution changes nonlinearly from the linear change period can be easily determined.

  Further, in the adsorption process in which ions in the aqueous solution are adsorbed to the ion adsorption electrode 1 by applying a voltage between the ion adsorption electrode 1 and the counter electrode 2 by the DC power source E, the ion adsorption electrode 1 and the counter electrode 2 are The amount of ions adsorbed on the ion adsorption electrode 1 can be accurately calculated by the ion amount calculation unit 30d based on the amount of current flowing during

  Here, since the DC power source E is a constant current source that outputs a constant current, the ion amount calculation unit 30d causes the constant current to flow between the ion adsorption electrode 1 and the counter electrode 2 and the energization time (linearity of the conductivity of the aqueous solution). The amount of ions adsorbed on the ion adsorption electrode 1 can be calculated more accurately by obtaining the amount of processing current that is the product of the change period).

  Similarly, in the desorption process in which ions are desorbed from the ion adsorption electrode 1 into the aqueous solution by applying a voltage between the ion adsorption electrode 1 and the counter electrode 2 by the direct current power source E, the ion adsorption electrode 1 by the direct current power source E is used. The amount of ions desorbed from the ion adsorption electrode 1 is accurately calculated by the ion amount calculation unit 30d based on the voltage applied between the ion adsorption electrode 1 and the current flowing between the ion adsorption electrode 1 and the counter electrode 2. be able to.

  Since the DC power source E is a constant voltage source that outputs a constant voltage, the ion amount calculation unit 30d causes the average current amount to flow between the ion adsorption electrode 1 and the counter electrode 2 and the energization time (linear change in conductivity of the aqueous solution). The amount of ions adsorbed on the ion-adsorbing electrode 1 can be calculated more accurately by obtaining the amount of processing current that is the product of (period).

[Third Embodiment]
Next, a functional water generating apparatus according to a third embodiment of the present invention will be described.

  The conventional functional water generator uniquely ends the adsorption / desorption treatment at the time when the specification of the intended pH or the like is reached in an aqueous solution having a high ion concentration. On the other hand, in the functional water generating apparatus according to the third embodiment of the present invention, if the processing efficiency can be continued in a state where the processing efficiency is high, the adsorption / desorption processing is continued within a range where high efficiency can be maintained. In this way, in the aqueous solution in which the adsorption / desorption treatment is continued, the amount of ions greatly fluctuates from the specification of the target functional water, so that it cannot be used directly as it is.

  However, in the functional water generating apparatus of the third embodiment, it is possible to adjust the target ion concentration by adding and diluting the untreated aqueous solution to the absorbed and desorbed aqueous solution. When the aqueous solution is taken from, a mechanism is used that is mixed with an untreated aqueous solution.

  In addition, this functional water generating device does not have a mixing function part with the untreated aqueous solution inside, and only has a function of discharging to the flow path (or holding tank) of the untreated aqueous solution outside the device. You may have. However, since the capacity when mixing the treated aqueous solution and the untreated aqueous solution is uniquely determined by the specifications of the target aqueous solution, it is necessary to have a device for managing the volume of the untreated aqueous solution.

  Below, an example when functional water of pH 4 is required is shown.

In 1 L (liter) of tap water at pH 7, 1 × 10 ⁻⁷ mol / L of hydrogen ions (H ⁺ ) are present. When 1 L functional water of pH 4 is finally desired, 1 L of functional water of pH 4 can be generated by generating acidic water of pH 3 in a 100 mL treatment tank 10 and mixing with 900 mL of untreated tap water. .

here,
Hydrogen ion concentration of treated water of pH 3: 1 × 10 ⁻³ mol / L
Hydrogen ion concentration of functional water at pH 4: 1 × 10 ⁻⁴ mol / L
Hydrogen ion concentration of tap water of pH 7: 1 × 10 ⁻⁷ mol / L
Because
Hydrogen ion concentration of functional water at pH 4 =
{(1 × 10 ⁻³ mol / L × 100 mL / 1 L) + (1 × 10 ⁻⁷ mol / L × 900 mL / 1 L)} ÷ 1 L≈1 × 10 ⁻⁴ mol / L
Thus, functional water having a target ion concentration can be generated. This can be similarly generated with respect to pH adjustment of alkaline water and hardness adjustment such as hard water and soft water if the ion concentration or the amount of ions per volume is determined.

In the above case, attention is focused on hydrogen ions (H ⁺ ), but in ion adsorption / desorption, if ions other than hydrogen ions (H ⁺ ) or hydroxide ions (OH ⁻ ) increase or decrease, the total number of ions is increased. In proportion to the amount of charge, hydrogen ions (H ⁺ ) increase and decrease in the case of positive ions, and hydroxide ions (OH ⁻ ) in the case of negative ions.

  FIG. 6 is a block diagram showing a basic configuration of a functional water generation system using the functional water generation apparatus according to the third embodiment of the present invention.

  As shown in FIG. 6, the functional water generating system of the present invention is a treatment tank 102 that performs adsorption / desorption of ions in an aqueous solution by the branch portion 101 of the untreated aqueous solution and the ion adsorption electrode 1 (shown in FIGS. 1 and 5). And a mixing unit 103 for mixing the aqueous solution processed in the processing tank 102 and the unprocessed aqueous solution from the branching unit 101, and controlling the processing tank 102, the branching unit 101, the processing tank 102 and the mixing unit 103. The processing control unit 110 is configured. The untreated aqueous solution branch 101 flows the untreated aqueous solution through the treatment tank 102 and the mixing unit 103.

  The said processing tank 102 has the structure similar to either of the functional water production | generation apparatuses of 1st, 2nd embodiment.

  Moreover, one of the electrodes of different polarities installed in the functional water generator is the ion adsorption electrode 1, the other is the counter electrode 2, and the counter electrode 2 side is composed of a Pt electrode. However, each electrode does not need to have a single structure, and may be divided into a plurality of parts. In addition, each electrode is installed so that the whole is submerged in an aqueous solution (a solution obtained by dissolving an auxiliary in tap water or tap water, or a dedicated solution) placed in the treatment tank 102. There is no problem if the entire electrode does not sink, but in this case, the area of the ion adsorption electrode 1 is reduced.

  When using local tap water as an aqueous solution, the ion concentration differs for each local tap water. Therefore, since the amount of ions contained in the aqueous solution varies from region to region, the treatment time that can be efficiently processed varies depending on the region. For this reason, functional water is generated by treating the aqueous solution in the treatment tank 102 in a treatment time according to the amount of ions in the region.

  Since the functional water generated in the treatment tank 102 has a variation in the amount of ions larger than the target ion control amount, an untreated aqueous solution is mixed in the mixing unit 103 so that the target ion amount is finally reached. To produce target functional water.

  The configuration diagram shown in FIG. 6 is a structure for keeping the specifications of the functional water when taken out, but in a system capable of performing processing in a state where it is stored in another tank at the time of use, the mixing unit 103 The structure of the system can be simplified by adopting a structure that eliminates the problem or a structure that discharges the untreated aqueous solution through the treatment tank 102.

  In the functional water generating device of the present invention, when the amount of the aqueous solution finally required is determined, it is not necessary to hold the aqueous solution in the treatment tank 102 more than necessary, and therefore the functional water generating device is charged with ions. By providing the concentration measurement function, it is possible to detect the amount of ions in the aqueous solution. If the amount of ions in the aqueous solution can be detected, the minimum required amount of aqueous solution can be calculated in reverse, so that it is not necessary to perform ion adsorption / desorption treatment on an excessive amount of aqueous solution.

[Fourth Embodiment]
FIG. 7: is a block diagram which shows the basic composition of the functional water production | generation system using the functional water production | generation apparatus of 4th Embodiment of this invention. The functional water generation system of the fourth embodiment has the same configuration as the functional water generation system of the third embodiment except for the drainage section 104. Moreover, it is set as the structure similar to the functional water production | generation apparatus of 2nd Embodiment provided with the function which calculates the amount of ions in the processing tank 102. FIG.

  When the ion concentration of the aqueous solution is low, it works favorably for reducing the ion concentration of the aqueous solution, but even if trying to increase the amount of ions, it is not possible to adsorb more ions than the amount of ions in the aqueous solution, It is not possible to control ions by desorbing more than the adsorbed ions. However, even when the amount of ions that can be adsorbed from the aqueous solution in a single treatment is small, the amount of ions necessary for ion concentration control is adsorbed to the ion adsorption electrode 1 by treating the adsorption treatment only a plurality of times while exchanging the aqueous solution. be able to.

  Therefore, in the functional water generating apparatus according to the fourth embodiment, an untreated aqueous solution is first placed in the treatment tank 102 and ion adsorption treatment in the aqueous solution is performed. An aqueous solution having a high ion concentration can adsorb more than the necessary amount of ions in one adsorption treatment, but if the ion concentration is low, the necessary amount of ions cannot be adsorbed only by this ion adsorption treatment. In normal processing, the treated aqueous solution is replaced with an untreated aqueous solution after draining, and ions are desorbed from the exchanged aqueous solution. Inability to produce water.

  For this reason, in the functional water generating apparatus of the fourth embodiment, the ion adsorption process is continuously performed without performing the ion desorption process, so that it is added to the previous ion adsorption amount and adsorbed on the ion adsorption electrode 1. The amount of ions to be increased can be increased. This ion adsorption treatment is performed a plurality of times until the necessary amount of ions is adsorbed. When the necessary amount of ions is adsorbed, the ion adsorption process is terminated, and the treated aqueous solution is discharged from the treatment tank 102 via the drainage unit 104, and the treatment tank 102 is replaced with the untreated aqueous solution. When ions adsorbed on the ion adsorption electrode 1 are desorbed again with respect to the exchanged aqueous solution, the treated aqueous solution becomes functional water having a target specification.

  In this functional water generating device, when the treated aqueous solution generated during the continuous ion adsorption treatment is necessary, the flow channel is opened to the mixing unit 103, and when unnecessary, the flow channel is opened to the drainage unit 104. It is configured to open and discharge.

  The untreated aqueous solution for diluting the treated aqueous solution does not need to pass through the functional water generating device unless it is required to have a constant specification at the outlet of the functional water generating device. In particular, when attaching to a system or the like that uses an untreated aqueous solution alone, there is no problem if it is a system that can input the required amount of the aqueous solution treated in the treatment tank 102. The system can be miniaturized by calculating the ratio and providing a mixing amount control function outside.

  In the functional water generators of the first to fourth embodiments, the change point at which the conductivity changes nonlinearly is detected, but the pH of the aqueous solution is detected using a pH meter, and the pH having a correlation with the conductivity is nonlinear. You may make it detect the changing point which changes.

  Since the functional water generation system of the third and fourth embodiments is a hydrostatic type, it has good ion adsorption performance and does not need to have a treatment tank of a capacity that is more than the final capacity, and generates functional water in the treatment tank. Even in the case of processing that requires a certain amount of processing time in a processing tank such as cleaning, functional water can be generated in parallel. In addition, in an apparatus that adjusts the ion concentration using an electric double layer, when a processing current equal to or higher than the current that forms the electric double layer is passed, water electrolysis occurs, resulting in a decrease in power efficiency. . For this reason, there is a problem that the processing efficiency decreases when the processing current is increased in order to speed up the processing time, but since parallel processing can be performed in batch processing using a processing tank, it is possible to perform processing efficiently. Become.

  When ion adsorption by an electric double layer is performed in an aqueous solution having a relatively low ion concentration in an aqueous solution such as tap water, if the ion concentration necessary for forming the electric double layer is sufficient, the treatment current and the amount of adsorbed ions are Correlation exists. When the ion concentration decreases, the slope is separated from the correlation line, so that the ion concentration in the aqueous solution can be measured based on the total current amount or the average processing current amount and the processing time until the point of departure from the correlation line.

  If hydrogen ions affect the formation of the electric double layer, adsorption of hydrogen ions with high ion mobility around the electrode precedes, followed by adsorption of ions other than hydrogen ions with low ion mobility. At the point of time, normal ion concentration changes are made. For this reason, the ion concentration in the aqueous solution can be measured by performing measurement except for the processing time in the equilibrium state at the time of hydrogen ion adsorption.

  In the generation of functional water, the change in conductivity correlates with the ion concentration of hydrogen ions and hydroxide ions. In the adsorption / desorption of ions using the electric double layer, the amount of hydrogen ions for positive ions and the amount of hydroxide ions for negative ions increase / decrease according to the charge polarity and valence of the adsorbed / desorbed ions. For this reason, the conductivity has a correlation with the amount of charge / desorption charges to the ion adsorption electrode 1 of positive ions or negative ions. For example, if the treatment current flowing between the ion adsorption electrode 1 and the counter electrode 2 is made constant, the treatment current amount and the ion adsorption / desorption amount have a correlation, so that the ion adsorption amount is sufficient if ions are sufficiently present in the aqueous solution. Is constant, and if there are sufficient ions in the ion adsorption electrode 1, the ion desorption amount is constant. In addition, since there is a correlation between the conductivity and the amount of ion adsorption / desorption, the amount of ion adsorption / desorption charge is calculated from the varying voltage with a constant processing current during the linear change period in which the change in conductivity is constant. Can be easily done.

  In addition, whether or not ion adsorption is performed efficiently is determined in the situation where the ion concentration around the ion adsorption electrode 1 is high, the variable value of the ion adsorption amount / input current amount is substantially constant. Since the variable value decreases as the value decreases, the efficiency of the ion adsorption / desorption state can be detected by monitoring the fluctuation of this value. Since there is a correlation between the ion adsorption amount and the conductivity, the adsorption efficiency can be monitored by monitoring the change in the conductivity.

  Also, when ion adsorption / desorption treatment is performed under constant current control, the change in conductivity is the same as the change in voltage applied between the ion adsorption electrode and the counter electrode, so the change in voltage is monitored. By doing so, it becomes possible to monitor the ion concentration.

  Although specific embodiments of the present invention have been described, the present invention is not limited to the above embodiments, and various modifications can be made within the scope of the present invention.

The functional water generator of this invention is
A container 10 containing an aqueous solution;
An ion-adsorbing electrode 1 disposed in the container 10 and capable of adsorbing and desorbing ions in the aqueous solution;
A counter electrode 2 disposed in the container 10 so as to face the ion-adsorbing electrode 1 with a space therebetween;
Voltage application means (E, SW1, SW2) for applying a voltage between the ion adsorption electrode 1 and the counter electrode 2;
An adsorption step in which ions in the aqueous solution are adsorbed to the ion adsorption electrode 1 by applying a voltage between the ion adsorption electrode 1 and the counter electrode 2 by the voltage application means (E, SW1, SW2) or the ion The desorption process of desorbing ions from the adsorption electrode 1 into the aqueous solution includes change point determination units 20a and 30b for determining a change point at which the change rate of the conductivity of the aqueous solution changes.

  According to the above configuration, the adsorption step (or the step of adsorbing ions in the aqueous solution to the ion adsorption electrode 1 by applying a voltage between the ion adsorption electrode 1 and the counter electrode 2 by the voltage application means (E, SW1, SW2) (or In the desorption step in which ions are desorbed from the ion adsorption electrode 1 into the aqueous solution), the change point determination unit 20a, 30b determines the change point at which the change rate of the conductivity of the aqueous solution changes, thereby improving the ion adsorption / desorption efficiency. Decrease can be detected. Therefore, when the ion adsorption / desorption efficiency starts to decrease, the ion adsorption / desorption is terminated, so that current does not continue to flow between the electrodes in a state where the ion adsorption / desorption efficiency is deteriorated. Ion adsorption / desorption can be efficiently processed according to the amount of ions adsorbed by the ion adsorption electrode 1.

Moreover, in the functional water generator of one embodiment,
The change point is a change point at which the conductivity of the aqueous solution changes nonlinearly after a linear change period in which the conductivity of the aqueous solution changes linearly.

  According to the above embodiment, in the adsorption process (or desorption process), the change point determination units 20a and 30b determine a change point where the conductivity of the aqueous solution changes nonlinearly after a linear change period in which the conductivity of the aqueous solution changes linearly. By determining, it is possible to reliably detect a decrease in ion adsorption / desorption efficiency.

Moreover, in the functional water generator of one embodiment,
A conductivity calculating unit 30a that calculates the conductivity of the aqueous solution based on the voltage applied between the ion adsorption electrode 1 and the counter electrode and the current flowing between the ion adsorption electrode 1 and the counter electrode is provided. ,
The change point determination unit 30b determines a change point at which the conductivity changes nonlinearly based on the conductivity of the aqueous solution calculated by the conductivity calculation unit 30a.

  Since the electrical conductivity of the aqueous solution has a correlation with the amount of positive and negative ions adsorbed and desorbed on the ion adsorption electrode 1, according to the embodiment, the voltage application means (E, SW1, SW2) causes the ion adsorption electrode. Based on the voltage applied between 1 and the counter electrode 2 and the current flowing between the ion-adsorbing electrode 1 and the counter electrode 2, the conductivity of the aqueous solution can be easily calculated by the conductivity calculator 30a.

Moreover, in the functional water generator of one embodiment,
A starting point determination unit 30c for determining a starting point at which a linear change period in which the conductivity of the aqueous solution linearly changes after a voltage is applied between the ion adsorption electrode 1 and the counter electrode 2 is provided.

  According to the above embodiment, when the voltage application means (E, SW1, SW2) is a constant current source, the conductivity of the aqueous solution changes linearly after the voltage is applied between the ion adsorption electrode 1 and the counter electrode 2. Until the linear change period begins, there is a period in which fluctuations in pH and conductivity are very small when positive ions are adsorbed to the ion adsorption electrode 1 and negative ions are desorbed from the ion adsorption electrode 1. The starting point determination unit 30c determines the starting point of the linear change period in which the conductivity of the aqueous solution changes linearly, and the voltage of the aqueous solution is linear after the voltage is applied between the ion adsorption electrode 1 and the counter electrode 2. Until the changing linear change period starts, the change point determination units 20a and 30b do not determine the change point of the conductivity of the aqueous solution, thereby accurately determining the change point of the conductivity of the aqueous solution. it can.

Moreover, in the functional water generator of one embodiment,
The voltage applying means (E, SW1, SW2) is a constant current source,
The change point determination units 20a and 30b determine the change point at which the voltage changes nonlinearly after a linear change period in which the voltage applied between the ion adsorption electrode 1 and the counter electrode 2 changes linearly. Is a change point where changes nonlinearly.

  According to the above-described embodiment, constant current control is performed so that a constant processing current flows between the ion adsorption electrode 1 and the counter electrode 2, so that a constant ion absorption with respect to the processing current can be obtained if sufficient ions exist in the aqueous solution. Since desorption is performed and the treatment current does not vary, the ion concentration in the aqueous solution varies due to ion adsorption / desorption, and the conductivity of the aqueous solution varies. Therefore, the voltage applied between the ion adsorption electrode 1 and the counter electrode 2 Shows the same behavior as the variation in conductivity. Thereby, in the constant current control, it is possible to detect the change in conductivity based on the change in the applied voltage, and the change point determination units 20a and 30b are applied between the ion adsorption electrode 1 and the counter electrode 2. A change point at which the voltage changes nonlinearly after a linear change period in which the voltage changes linearly is defined as a change point at which the conductivity of the aqueous solution changes nonlinearly. Therefore, based on the voltage applied between the ion adsorption electrode 1 and the counter electrode 2, the change point when the electrical conductivity of the aqueous solution changes nonlinearly from the linear change period can be easily determined.

Moreover, in the functional water generator of one embodiment,
In the adsorption step of adsorbing ions in the aqueous solution to the ion adsorption electrode 1 by applying a voltage between the ion adsorption electrode 1 and the counter electrode 2 by the voltage application means (E, SW1, SW2), Based on the amount of current flowing between the ion adsorption electrode 1 and the counter electrode 2, an ion amount calculation unit 30d for calculating the amount of ions adsorbed on the ion adsorption electrode 1 from the aqueous solution is provided.

  According to the above-described embodiment, in the adsorption step of adsorbing ions in the aqueous solution to the ion adsorption electrode 1 by applying a voltage between the ion adsorption electrode 1 and the counter electrode 2 by the voltage application means (E, SW1, SW2). Based on the amount of current flowing between the ion adsorbing electrode 1 and the counter electrode 2 from the voltage applying means (E, SW1, SW2), the ion amount calculating unit 30d accurately calculates the amount of ions adsorbed on the ion adsorbing electrode 1. can do.

DESCRIPTION OF SYMBOLS 1 ... Ion adsorption electrode 2 ... Counter electrode 10 ... Processing tank 11 ... Conductivity meter 20 ... Control apparatus 20a ... Change point determination part 20b ... Start point determination part 21 ... Voltmeter 22 ... Ammeter 30 ... Control apparatus 30a ... Conductivity calculation Unit 30b ... Change point determination unit 30c ... Start point determination unit 30d ... Ion amount calculation unit 101 ... Untreated solution branching unit 102 ... Treatment tank 103 ... Mixing unit 104 ... Drainage unit 110 ... Treatment control unit E ... DC power supply SW1, SW2 switch

Claims (6)

A container for containing an aqueous solution;
An ion adsorption electrode disposed in the container and capable of adsorbing and desorbing ions in the aqueous solution;
A counter electrode disposed in the container so as to face the ion-adsorbing electrode with a space therebetween;
Voltage application means for applying a voltage between the ion adsorption electrode and the counter electrode;
The voltage application means applies a voltage between the ion adsorption electrode and the counter electrode to adsorb ions in the aqueous solution to the ion adsorption electrode, or removes ions from the ion adsorption electrode into the aqueous solution. A functional water generating apparatus, comprising: a change point determination unit that determines a change point at which the change rate of the conductivity of the aqueous solution changes in the separation step. In the functional water generating apparatus according to claim 1,
The functional water generating device, wherein the change point is a change point where the conductivity of the aqueous solution changes nonlinearly after a linear change period in which the conductivity of the aqueous solution changes linearly. In the functional water generating apparatus according to claim 1 or 2,
A conductivity calculator that calculates the conductivity of the aqueous solution based on the voltage applied between the ion adsorption electrode and the counter electrode and the current flowing between the ion adsorption electrode and the counter electrode;
The function water generating device, wherein the change point determination unit determines a change point where the conductivity changes nonlinearly based on the conductivity of the aqueous solution calculated by the conductivity calculation unit. In the functional water generating apparatus according to any one of claims 1 to 3,
A functional water comprising a start point determination unit for determining a start point at which a linear change period in which the conductivity of the aqueous solution changes linearly after a voltage is applied between the ion adsorption electrode and the counter electrode Generator. In the functional water generating apparatus according to claim 1 or 2,
The voltage applying means is a constant current source,
The change point determination unit is a change point in which the conductivity of the aqueous solution changes in a nonlinear manner at a change point in which the voltage changes in a nonlinear manner after a linear change period in which the voltage applied between the ion adsorption electrode and the counter electrode changes in a linear manner. A functional water generator characterized by a point. In the functional water generating apparatus according to any one of claims 1 to 5,
In an adsorption step of adsorbing ions in the aqueous solution to the ion adsorption electrode by applying a voltage between the ion adsorption electrode and the counter electrode by the voltage application means, between the ion adsorption electrode and the counter electrode. A functional water generating apparatus comprising an ion amount calculation unit that calculates the amount of ions adsorbed to the ion adsorption electrode from the aqueous solution based on the amount of current that flows.

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