JP3495722B2 - Hypochlorous acid generation system - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a system for applying a voltage between an anode and a cathode to generate hypochlorous acid in water to be treated by electrolysis.

[0002]

2. Description of the Related Art Conventionally, as for water to be treated, which is used especially in pools and the like, a sanitizer such as a chlorine-based chemical is added to stored tap water to keep the water to be treated hygienic. However, in such a disinfection method of drug input,
There was a problem that the concentration of the chemical in the water to be treated was measured, and when the concentration was less than a predetermined value, the chemical had to be further charged, and the maintenance work was complicated.

On the other hand, as a method of disinfecting and sterilizing water to be treated, usually, hypochlorous acid is generated in the water to be treated by electrolysis, and the water to be treated is sterilized by the hypochlorous acid. In this case, for example, an electrolytic bath is provided near the pool in which the water to be treated is stored, and the water to be treated that has been treated in the electrolytic bath is added to the pool. In this electrolytic cell,
For example, a pair of electrodes is immersed in treated water, and a voltage is applied to the electrodes to electrolyze the water to be treated.

As a result, chloride ions contained in the water to be treated in the electrolytic cell are subjected to electrolysis, and hypochlorous acid is generated from the electrode surface. With this hypochlorous acid, microorganisms such as mold and bacteria contained in the water to be treated were sterilized.

[0005]

However, tap water which is usually used as water to be treated is dilute chlorine water, and therefore, when hypochlorous acid is generated using such water to be treated, the tap water should be continuously treated. When a voltage is applied between the anode and the cathode, the concentration of chloride ions supplied in the vicinity of the anode is significantly insufficient, and as a result, there is a problem that the current efficiency due to chlorine generation is reduced. Further, there has been a problem that the amount of chlorine generated and the amount of hypochlorous acid generated with respect to the amount of electric power significantly decrease with the decrease in current efficiency.

Therefore, the present invention has been made to solve the conventional technical problems, and can efficiently generate hypochlorous acid even under dilute chloride ion conditions. It is intended to provide a hypochlorous acid generating system.

[0007]

DISCLOSURE OF THE INVENTION The present invention is a system for applying a voltage between an anode and a cathode to generate hypochlorous acid in water to be treated by electrolysis. A control device for controlling is provided, and the control device periodically changes the voltage applied between the cathode and the anode between a predetermined maximum value and a minimum value based on the concentration of chloride ions in the water to be treated. Is characterized by.

According to the present invention, a system for applying a voltage between the anode and the cathode to generate hypochlorous acid in the water to be treated by electrolysis, the control device controlling the voltage applied between the cathode and the anode. This control device changes the voltage applied between the cathode and the anode periodically between a predetermined maximum value and a minimum value based on the concentration of chloride ions in the water to be treated. With the voltage applied between the cathode and the anode at the specified maximum value, the chloride ions supplied near the anode are converted to chlorine, and the voltage applied between the cathode and the anode becomes the specified minimum value. In this state, it is possible to eliminate the insufficient supply of chloride ions near the anode.

As a result, especially when the concentration of chloride ions in the water to be treated is low, the current caused by the chronic shortage of chloride ions due to the continuous application of the maximum voltage between the cathode and the anode. Since it is possible to remarkably avoid a decrease in efficiency, it is possible to save power consumption.

According to the hypochlorous acid generating system of the invention of claim 2, in addition to the invention of claim 1, the control device has a maximum value of 3
The voltage is set to V to 100V, and the minimum value is set to a voltage lower than the maximum value and equal to or higher than zero. Based on the concentration of chloride ions in the water to be treated, these maximum and minimum voltages are fixed between the cathode and the anode. It is characterized in that the voltage is alternately applied in the cycle.

According to the hypochlorous acid generating system of the second aspect of the present invention, in addition to the first aspect of the invention, the control device sets the maximum value to a voltage of 3V to 100V, and sets the minimum value to be higher than the maximum value. The voltage of the maximum value and the minimum value is alternately applied at a constant cycle between the cathode and the anode based on the concentration of chloride ions in the water to be treated as a voltage of 0 or more. By setting the voltage applied between them to the maximum value of 3 V to 100 V, it becomes possible to convert chloride ions supplied to the vicinity of the anode to chlorine at an appropriate voltage,
Along with this, it becomes possible to improve the generation rate of hypochlorous acid.

Then, by controlling the voltage applied between the cathode and the anode by the control device to be a voltage lower than the maximum value and at a minimum value of zero or more, it is possible to eliminate the insufficient supply of chloride ions near the anode. Like

In the hypochlorous acid generating system according to the third aspect of the present invention, in addition to the first or second aspect of the present invention, the control device controls the concentration of chloride ions in the treated water in the treated water. It is characterized in that it has a conductivity detecting means for detecting the conductivity, and changes the period for applying the minimum voltage during one cycle based on the output of this conductivity detecting means.

According to the hypochlorous acid generating system of the invention of claim 3, in addition to the invention of claim 1 or claim 2, the control device controls the treatment target based on the concentration of chloride ions in the treatment water. The conductivity detecting means for detecting the conductivity in water is provided, and the period for applying the minimum voltage during one cycle is changed based on the output of the conductivity detecting means. It is possible to grasp the concentration of chloride ions in the water to be treated, and this makes it possible to change the application period of the minimum applied voltage in one cycle of the voltage applied between the cathode and the anode. Become.

Therefore, when the conductivity in the water to be treated is lower than a predetermined value, the application period of the minimum applied voltage in one cycle of the voltage applied between the cathode and the anode is lengthened to thereby increase the vicinity of the anode. It becomes possible to eliminate the shortage of supply of chloride ions to the column and to remarkably avoid the decrease in current efficiency due to the shortage of chloride ions. As a result, the efficiency of hypochlorous acid generation with respect to the supplied current can be improved.

Further, when the conductivity in the water to be treated is higher than a predetermined value, the application period of the minimum applied voltage in one cycle of the voltage applied between the cathode and the anode is shortened to shorten the period. It becomes possible to accelerate the generation of chlorine and hypochlorous acid while efficiently supplying chloride ions to the anode.

In the hypochlorous acid generating system according to a fourth aspect of the present invention, in addition to the first or second aspect of the present invention, the control device is arranged so that the cathode and the anode are separated based on the concentration of chloride ions in the water to be treated. The present invention is characterized in that it has a current value detecting means for detecting the current value of, and the period for applying the minimum value voltage in one cycle is changed based on the output of the current value detecting means.

According to the hypochlorous acid generating system of the invention of claim 4, in addition to the invention of claim 1 or claim 2, the control device determines that the cathode and the cathode are based on the concentration of chloride ions in the water to be treated. The current value detecting means for detecting the current value between the anodes is provided, and the period for applying the minimum value voltage in one cycle is changed based on the output of the current value detecting means. The concentration of chloride ions in the water to be treated can be ascertained, and the minimum applied voltage in one cycle of the voltage applied between the cathode and the anode can be determined according to the current value between the cathode and the anode. It becomes possible to change the application period.

Therefore, when the detected current value is lower than the predetermined value, the application period of the minimum applied voltage in one cycle of the voltage applied between the cathode and the anode is lengthened to bring it to the vicinity of the anode. It is possible to eliminate the insufficient supply of chloride ions, and it is possible to remarkably avoid a decrease in current efficiency due to a shortage of chloride ions. Thereby, the generation efficiency of hypochlorous acid with respect to the supplied current can be improved.

When the detected current value is higher than the predetermined value, the application period of the minimum applied voltage in one cycle of the voltage applied between the cathode and the anode is shortened to shorten the period. It becomes possible to promote the generation of chlorine and hypochlorous acid while efficiently supplying chloride ions to the anode.

In the hypochlorous acid generating system according to a fifth aspect of the present invention, in addition to the third or fourth aspect of the present invention, the control device is such that when the conductivity detected by the conductivity detecting means is low, or the current is low. When the current value output by the value detecting means is low, the period for applying the minimum voltage in one cycle is lengthened.

According to the hypochlorous acid generating system of the fifth aspect of the present invention, in addition to the third or fourth aspect of the present invention, the control device is such that when the conductivity detected by the conductivity detecting means is low,
Alternatively, when the current value output by the current value detection means is low, the period for applying the minimum voltage during one cycle is lengthened,
The control device makes it possible to extend the period for applying the minimum voltage during one cycle if necessary, and it is possible to significantly avoid the current efficiency drop caused by chronic chloride ion shortage. it can.

The hypochlorous acid generating system according to the invention of claim 6 is, in addition to the invention of claim 3, claim 4 or claim 5,
The control device is characterized in that the maximum voltage is continuously applied when the conductivity output by the conductivity detection unit is high or when the current value output by the current value detection unit is high.

According to the hypochlorous acid generating system of the invention of claim 6, in addition to the invention of claim 3, claim 4 or claim 5, the control device has a conductivity detected by the conductivity detecting means. Is high, or the current value output by the current value detection means is high, the maximum voltage is continuously applied,
It becomes possible to improve the electrolysis efficiency when chronic chloride ion deficiency does not occur.

[0025]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 1 is an explanatory diagram showing an outline of a hypochlorous acid generator 1 for realizing the hypochlorous acid generation system of the present invention. The hypochlorous acid generator 1 in this embodiment is for sterilizing tap water as water to be treated stored in a storage tank (not shown) such as a pool, and is a treatment provided in communication with the storage tank. It is installed in tank 2. The water to be treated stored in the storage tank and the processing tank 2 is circulated in the storage tank and the processing tank 2 by a pump or the like not shown.

The processing tank 2 has a rectangular shape, and a processing chamber 5 is formed inside. An inflow port 3 is formed in the lower part of one surface forming the side wall of the treatment tank 2 so that the water to be treated flowing out from the storage tank is introduced into the treatment chamber 5. Further, an outlet 4 is formed in the upper part of the side wall at a position facing the side wall of the treatment tank 2 in which the inlet 3 is formed, for discharging the water to be treated in the treatment chamber 5 into the storage tank. There is.

A plurality of electrodes, at least a part of which is immersed in the water to be treated in the treatment chamber 5, that is, an anode 6 and a cathode 7 are arranged. The anode 6 and the cathode 7 are provided with a power supply 25 for energizing the anode 6 and the cathode 7, and the power supply 25 is connected to a control device 22 that controls the voltage applied to the anode 6 and the cathode 7. Connected.

The anode 6 is a plate-like electrode made of a conductive material containing at least one of a noble metal or a metal oxide such as platinum, iridium or palladium. The anode 6 used in this example is a plate-shaped electrode made of palladium.

The cathode 7 is an electrode made of a conductive material, and is a plate-shaped electrode made of titanium in this embodiment. Here, the plate-shaped electrode of the cathode 7 is
The surface area is at least larger than that of the anode 6.

In the hypochlorous acid generator 1 of this embodiment, the cathode 7 has a large area, that is, the parallel portion 7A is perpendicular to the side wall where the inlet 3 and the outlet 4 are formed. A plurality of them are installed at predetermined intervals. Then, the anodes 8 are arranged between the parallel portions 7A of the cathodes 7, respectively. At this time, the cathode 7 and the anode 6
The distance between and is 0.5 cm or more and 2.0 cm or less. As a result, the surface of the anode 8 having a large area, that is, the parallel portion is the parallel portion 7A of the cathode 7.
Will be surrounded by.

At this time, since the distance between the cathode 7 and the anode 6 is 0.5 cm or more and 2.0 cm or less, the water to be treated surrounded by the cathode 7 is the anode 6 The chloride ions are allowed to easily flow toward, and the concentration of chloride ions around the anode 6 is increased. Therefore, the chlorine generation efficiency in the anode 6 is improved, and along with this, the hypochlorous acid generation efficiency is also improved.

With the above configuration, the parallel portion 7 of the cathode 7
A plurality of A are provided at a predetermined interval, and the anodes 6 are respectively disposed between the parallel portions 7A, which makes it possible to obtain a hypochlorous acid generation efficiency suitable for practical use with a simple structure. The chlorous acid generator can be configured.

Further, the cathodes 7 may be connected to each other by connecting members 8 as shown in FIGS. The connecting members 8 and 8 are provided on the side surface of each cathode 7,
That is, the surfaces facing the inflow port 3 and the outflow port 4 formed in the processing tank 2 are connected to each other and are made of a conductive material. Further, the connecting members 8 and 8 are formed of the conductive material in a grid shape, and are configured to ensure water permeability of the portion of the cathode 7 other than the parallel portion 7A.

The cathode 7 in the present invention is different from the above embodiment in that the cathode 6 is spaced apart from the anode 6 by a predetermined distance.
Around the side surface of the plate-shaped cathode 7, for example, 360
It may have a cylindrical shape that surrounds over time or a substantially cylindrical shape.

At this time, at least the surface having the largest surface area of the anode 6, that is, the portion other than the parallel portion of the cathode 7 positioned parallel to the front and rear surfaces has a water-permeable structure, for example, a mesh structure or It is assumed to have a hole structure. In addition to this, the entire cathode 7 may have a structure having water permeability.

As a result, the water to be treated surrounded by the cathode 7 has a structure in which chloride ions flow toward the anode 6, so that the concentration of chloride ions around the anode 6 is increased. Therefore, the chlorine generation efficiency in the anode 6 is improved, and along with this, the hypochlorous acid generation efficiency is also improved.

On the other hand, below the processing chamber 5, a stirring device for stirring the water to be treated in the processing chamber 5 is provided. The stirring device in this embodiment is composed of a bubble generating device 9 that stirs the water to be treated by generating bubbles. The operation of the bubble generator 9 is performed in conjunction with the energization of the anode 6 and the cathode 7.

On the other hand, the control device 22 is composed of a general-purpose microcomputer as shown in FIG.
A conductivity sensor 20 is connected to the input side of the control device 22 as a conductivity detecting means for detecting the conductivity of the water to be treated. The conductivity sensor 20 is arranged between the cathode 7 and the anode 6 as shown in FIG. The conductivity sensor 20 is provided on the input side of the control device 22.
Instead of this, a current value detecting device 26 as a current value detecting means for detecting the current value between the anode 6 and the cathode 7 may be connected. It should be noted that both the conductivity sensor 20 and the current value detection device 26 may be connected. Further, the power source 25 is connected to the output side of the control device 22.

With the above configuration, the processing chamber 5 in the processing tank 2
To be treated water from a storage tank such as a pool and store the storage tank up to the position of the outlet 4 formed in the processing tank 2,
The controller 22 turns on the power source to energize each anode 6 and cathode 7. The current density of the cathode 7 at this time is 0.5 A / (dm) ² or more and 2.0 A / (d
m) ² or less.

At this time, the bubble generating device 9 as a stirring device is also operated to generate bubbles in the processing chamber 5, whereby the water to be treated is stirred. Incidentally, the water to be treated flowing from the storage tank always flows from the storage tank,
Although it circulates in the processing chamber 5, it returns to the storage tank through the outlet 4.

As a result, the microorganisms contained in the water to be treated are attracted to the anode 6 which has a positive potential because they are generally charged to a negative potential. Further, at the anode 6, chloride ions contained in a predetermined amount of water to be treated release electrons to generate chlorine. Then, this chlorine dissolves in water and produces hypochlorous acid. As a result, in the vicinity of the anode 6, the chlorine or hypochlorous acid kills the microorganisms in the water to be treated.

By the way, when the concentration of chloride ions in the water to be treated is low, the concentration of chloride ions supplied to the anode 6 side is lowered, so that the reaction of converting chloride ions to chlorine is delayed. As a result, the efficiency of chlorine generation decreases with respect to the voltage applied by the power supply 25, and the efficiency of hypochlorous acid generation deteriorates.

Therefore, the control device 22 according to the present invention.
Changes the voltage applied between the cathode 7 and the anode 6 periodically between a predetermined maximum value and a minimum value based on the concentration of chloride ions in the water to be treated, as shown in FIG.

As a result, even when the chloride ion concentration in the water to be treated is low, the voltage applied between the cathode 7 and the anode 6 periodically changes between a predetermined maximum value and minimum value. Therefore, the chloride ion supplied to the vicinity of the anode 6 is converted into chlorine in the state where the maximum voltage is applied to the treated water, and the minimum voltage is applied to the treated water. Insufficient supply of chloride ions to the vicinity of the anode 6 can be eliminated.

Therefore, it is possible to remarkably avoid a decrease in current efficiency caused by chronic shortage of chloride ions due to the continuous application of the maximum voltage between the cathode 7 and the anode 6, so that the power consumption is reduced. It is possible to save electricity. In addition, since the power source 25 generates an appropriate amount of chlorine with respect to the amount of electric power, it becomes possible to efficiently generate hypochlorous acid.

The controller 22 includes a cathode 7 and an anode 6
By periodically changing the voltage applied between the maximum and minimum values, it is possible to avoid a decrease in current efficiency caused by a chronic shortage of chloride ions in the water to be treated. The periodical change of the voltage value means that the applied voltage including the maximum value and the minimum value is changed in multiple steps in addition to the pulse application for alternately changing the maximum value and the minimum value. , Shall have the same effect.

In particular, the maximum applied voltage applied between the cathode 7 and the anode 6 by the controller 22 is 3V to 1V.
With a voltage of 00 V, the minimum value of the applied voltage is lower than the maximum value and is equal to or higher than zero, and the maximum value and the minimum value are alternately pulsed at a constant cycle. With the applied voltage applied, the chloride ions supplied to the vicinity of the anode 6 can be converted into chlorine at an appropriate voltage. Further, it is possible to eliminate the insufficient supply of chloride ions to the vicinity of the anode 6 in a state where the minimum applied voltage is applied to the water to be treated or a state where no voltage is applied.

Further, the control device 22 in this embodiment is
The chloride ion concentration of the water to be treated is determined based on the output of the conductivity sensor 20 or the output of the current value detection device 26, thereby changing the period for applying the minimum voltage in one cycle.

That is, when the chloride ion concentration of the water to be treated is determined based on the output of the conductivity sensor 20, when the conductivity sensor 20 detects that the conductivity of the water to be treated is lower than a predetermined value, The application period of the minimum applied voltage is made longer than the application period of the minimum applied voltage in one cycle of the voltage normally applied between the cathode 7 and the anode 6.

Thus, by easily grasping the concentration of chloride ions in the water to be treated, the shortage of supply of chloride ions in the vicinity of the anode 6 can be resolved, and the maximum voltage between the cathode 7 and the anode 6 can be obtained. It becomes possible to eliminate the deficiency of chloride ions caused by the application, and to avoid a decrease in current efficiency remarkably. Therefore, the efficiency of hypochlorous acid generation with respect to the supplied current value can be improved.

In addition, the control device 22 uses the conductivity sensor 20.
When the electric conductivity in the water to be treated is detected to be higher than a predetermined value, the minimum applied voltage is applied to the cathode 7 and the anode 6 in a cycle of the minimum applied voltage during one cycle. The voltage application period is shortened.

As a result, it is possible to promote the generation of chlorine while efficiently supplying chloride ions to the anode 6, and to improve the hypochlorous acid generation efficiency.

It should be noted that a plurality of predetermined values of the electrical conductivity, which serve as a reference for the control device 22 to determine, may be set, whereby the application period of the minimum applied voltage can be changed stepwise, It is possible to efficiently promote the generation of chlorine and hypochlorous acid.

In addition, the control device 22 controls the conductivity sensor 20.
When a predetermined high value is detected, the control for periodically changing the voltage applied between the cathode 7 and the anode 6 by the power supply 25 between the predetermined maximum value and the minimum value is stopped, and the maximum value is applied. The voltage may be continuously applied.

As a result, when the water to be treated contains a sufficient amount of chloride ions and the chloride ions for generating chlorine and hypochlorous acid are sufficient, the cathode 7 is sufficiently supplied.
A voltage can be applied between the anode 6 and the anode 6, and the generation efficiency of chlorine and hypochlorous acid can be improved.

On the other hand, when the chloride ion concentration of the water to be treated is determined based on the output of the current value detecting device 26, the anode 6 is controlled similarly to the control based on the output of the conductivity sensor 20.
When the current value between the cathode 7 and the cathode 7 is detected to be lower than a predetermined value, the minimum value of the voltage applied between the normal cathode 7 and the anode 6 in one cycle is applied to the minimum value of the applied voltage. Extend the voltage application period.

Thus, similarly to the above, by easily grasping the concentration of chloride ions in the water to be treated, the shortage of supply of chloride ions to the vicinity of the anode 6 is eliminated, and the current due to the shortage of chloride ions It becomes possible to avoid a decrease in efficiency remarkably. Therefore, the generation efficiency of hypochlorous acid with respect to the supplied current can be improved.

Further, the control device 22 uses the current value detection device 2
When the current value detected by 6 is higher than a predetermined value,
The application period of the minimum applied voltage is shortened as compared with the application period of the minimum applied voltage in one cycle of the voltage normally applied between the cathode 7 and the anode 6.

As a result, it becomes possible to promote the generation of chlorine and hypochlorous acid while efficiently supplying chloride ions to the anode 6.

It should be noted that a plurality of predetermined current values serving as a reference for the control device 22 may be set, whereby the application period of the minimum applied voltage can be changed stepwise, It is possible to efficiently promote the generation of chlorine and hypochlorous acid.

Further, the control device 22 uses the current value detection device 2
6 detects a predetermined high value, the control for periodically changing the voltage applied between the cathode 7 and the anode 6 by the power supply 25 between the predetermined maximum value and the minimum value is stopped, and The applied voltage may be continuously applied.

As a result, when the water to be treated contains a sufficient amount of chloride ions and the amount of chloride ions for generating chlorine and hypochlorous acid is sufficient, the cathode 7 is sufficiently supplied.
A voltage can be applied between the anode 6 and the anode 6, and the efficiency of hypochlorous acid generation can be further improved.

[0063]

As described above in detail, according to the present invention, a voltage is applied between the anode and the cathode to generate hypochlorous acid in the water to be treated by electrolysis, which is applied between the cathode and the anode. A control device for controlling the voltage to be applied, and the control device controls the voltage applied between the cathode and the anode based on the concentration of chloride ions in the water to be treated.
Since it changes periodically between a predetermined maximum value and minimum value,
With the voltage applied between the cathode and the anode set to a specified maximum value by the controller, the chloride ions supplied near the anode are converted to chlorine, and the voltage applied between the cathode and the anode is adjusted to the specified value. With the minimum value,
Insufficient supply of chloride ions near the anode can be eliminated.

As a result, in particular, when the concentration of chloride ions in the water to be treated is low, the current caused by the chronic shortage of chloride ions due to the continuous application of the maximum voltage between the cathode and the anode. Since it is possible to remarkably avoid a decrease in efficiency, it is possible to save power consumption.

According to the hypochlorous acid generating system of the second aspect of the invention, in addition to the first aspect of the invention, the control device sets the maximum value to a voltage of 3V to 100V, and sets the minimum value to a value higher than the maximum value. The voltage of the maximum value and the minimum value is alternately applied at a constant cycle between the cathode and the anode based on the concentration of chloride ions in the water to be treated as a voltage of 0 or more. By setting the voltage applied between them to the maximum value of 3 V to 100 V, it becomes possible to convert chloride ions supplied to the vicinity of the anode to chlorine at an appropriate voltage,
Along with this, it becomes possible to improve the generation rate of hypochlorous acid.

Then, by controlling the voltage applied between the cathode and the anode by the controller to be a voltage lower than the maximum value and at a minimum value of zero or more, it is possible to eliminate the insufficient supply of chloride ions near the anode. Like

According to the hypochlorous acid generating system of the invention of claim 3, in addition to the invention of claim 1 or claim 2, the control device controls the treatment target based on the concentration of chloride ions in the treatment water. The conductivity detecting means for detecting the conductivity in water is provided, and the period for applying the minimum voltage during one cycle is changed based on the output of the conductivity detecting means. It is possible to grasp the concentration of chloride ions in the water to be treated, and this makes it possible to change the application period of the minimum applied voltage in one cycle of the voltage applied between the cathode and the anode. Become.

Therefore, when the conductivity in the water to be treated is lower than the predetermined value, the application period of the minimum applied voltage in one cycle of the voltage applied between the cathode and the anode is lengthened so that the vicinity of the anode is increased. It becomes possible to eliminate the shortage of supply of chloride ions to the column and to remarkably avoid the decrease in current efficiency due to the shortage of chloride ions. As a result, the efficiency of hypochlorous acid generation with respect to the supplied current can be improved.

When the conductivity of the water to be treated is higher than a predetermined value, the application period of the minimum applied voltage in one cycle of the voltage applied between the cathode and the anode is shortened to shorten the period. It becomes possible to accelerate the generation of chlorine and hypochlorous acid while efficiently supplying chloride ions to the anode.

According to the hypochlorous acid generating system of the invention of claim 4, in addition to the invention of claim 1 or claim 2, the control device determines that the cathode and cathode are based on the concentration of chloride ions in the water to be treated. The current value detecting means for detecting the current value between the anodes is provided, and the period for applying the minimum value voltage in one cycle is changed based on the output of the current value detecting means. The concentration of chloride ions in the water to be treated can be ascertained, and the minimum applied voltage in one cycle of the voltage applied between the cathode and the anode can be determined according to the current value between the cathode and the anode. It becomes possible to change the application period.

Therefore, when the detected current value is lower than the predetermined value, the application period of the minimum applied voltage in one cycle of the voltage applied between the cathode and the anode is lengthened to bring the voltage to the vicinity of the anode. It is possible to eliminate the insufficient supply of chloride ions, and it is possible to remarkably avoid a decrease in current efficiency due to a shortage of chloride ions. Thereby, the generation efficiency of hypochlorous acid with respect to the supplied current can be improved.

When the detected current value is higher than the predetermined value, the application period of the minimum applied voltage in one cycle of the voltage applied between the cathode and the anode is shortened to shorten the period. It becomes possible to promote the generation of chlorine and hypochlorous acid while efficiently supplying chloride ions to the anode.

According to the hypochlorous acid generating system of the invention of claim 5, in addition to the invention of claim 3 or 4, the control device is such that when the conductivity detected by the conductivity detecting means is low,
Alternatively, when the current value output by the current value detection means is low, the period for applying the minimum voltage during one cycle is lengthened,
The control device makes it possible to extend the period for applying the minimum voltage during one cycle if necessary, and it is possible to significantly avoid the current efficiency drop caused by chronic chloride ion shortage. it can.

According to the hypochlorous acid generating system of the invention of claim 6, in addition to the invention of claim 3, claim 4 or claim 5, the control device has the conductivity detected by the conductivity detecting means. Is high, or the current value output by the current value detection means is high, the maximum voltage is continuously applied,
It becomes possible to improve the electrolysis efficiency when chronic chloride ion deficiency does not occur.

[Brief description of drawings]

FIG. 1 is a schematic explanatory view of a hypochlorous acid generator of the present invention.

FIG. 2 is a perspective view of a cathode.

FIG. 3 is a schematic view of a hypochlorous acid generator.

FIG. 4 is an electrical block diagram of a control device.

FIG. 5 is an explanatory diagram showing a cycle of a voltage applied to a cathode and an anode.

[Explanation of symbols]

Primary hypochlorous acid generator 2 processing tanks 3 Inlet 4 Outlet 5 processing room 6 anode 7 cathode 20 Conductivity sensor 22 Control device 25 power 26 Current value detector

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI C02F 1/50 560 C02F 1/50 560F C25B 1/26 C25B 1/26 C 9/00 9/00 A (56) References Special Kaihei 7-163982 (JP, A) JP 3-254888 (JP, A) JP 3-293093 (JP, A) JP 6-165987 (JP, A) JP 2000-126774 (JP , A) JP-A-11-262772 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) C02F 1/46 C02F 1/50 C25B 1/26 C25B 9/00

Claims (6)

(57) [Claims] 1. A voltage is applied between the anode and the cathode,
A system for generating hypochlorous acid in water to be treated by electrolysis, comprising a controller for controlling a voltage applied between the cathode and the anode, wherein the controller controls the concentration of chloride ions in the water to be treated. Based on the above, the hypochlorous acid generating system is characterized in that the voltage applied between the cathode and the anode is periodically changed between a predetermined maximum value and a minimum value. 2. The control device sets the maximum value to a voltage of 3V to 100V, sets the minimum value to a voltage lower than the maximum value and equal to or more than zero, and processes the maximum and minimum voltages. 2. The hypochlorous acid generating system according to claim 1, wherein the cathode and the anode are alternately applied at a constant cycle based on the concentration of chloride ions in the water. 3. The control device has a conductivity detection unit for detecting the conductivity of the water to be treated based on the concentration of chloride ions in the water to be treated, and based on the output of the conductivity detection unit, The hypochlorous acid generating system according to claim 1 or 2, wherein a period for applying the minimum voltage in one cycle is changed. 4. The control device has current value detection means for detecting a current value between the cathode and the anode based on the concentration of chloride ions in the water to be treated, and based on the output of the current value detection means. The hypochlorous acid generating system according to claim 1 or 2, wherein the period for applying the minimum voltage during one cycle is changed. 5. The controller controls the voltage of the minimum value during one cycle when the conductivity output by the conductivity detection unit is low or when the current value output by the current value detection unit is low. The hypochlorous acid generating system according to claim 3 or 4, wherein the application period is extended. 6. The control device continuously applies the voltage of the maximum value when the conductivity output by the conductivity detection unit is high or when the current value output by the current value detection unit is high. The hypochlorous acid generating system according to claim 3, 4, or 5, wherein