JP2008200636A - Water treatment method and apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a water treatment method and apparatus having both of a scale deposition preventing function and a gaseous hydrogen diluting function and capable of miniaturizing the apparatus. <P>SOLUTION: The water treatment apparatus is provided with a circulation tank 10 to which raw water 20 flows-in and from which gaseous hydrogen produced by electrolysis is discharged, an electrolytic bath 13 for electrolyzing the raw water supplied from the circulation tank through a circulation pump 11 in the presence of chloride ion and a circulation line 23 for circulating at least a part of the treated water discharged from the electrolytic bath to the circulation tank, and further an air supply means (compressor 12) for supplying air in the quantity necessary to secure the flow rate in the bath and to correspond to the dilution of the gaseous hydrogen is provided at the upstream side of the electrolytic bath 13 or in the electrolytic bath 13. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a water treatment method and apparatus for electrolytically treating water to be treated, and more particularly to an efficient water treatment method and apparatus capable of preventing adhesion of scale components to electrodes.

Conventionally, as one of water treatment technologies, electrolytic treatment has been widely used in various fields. In the electrolytic treatment, hypochlorous acid is generated by electrolyzing the water to be treated in the presence of chloride ions, and the oxide contained in the oxide-containing water is oxidized and decomposed by the hypochlorite. .
Patent Document 1 (Japanese Patent Laid-Open No. 2004-202484) discloses a hypochlorous acid-based strong oxidizing substance by electrolytically treating a separated liquid obtained by solid-liquid separation of digested sludge after methane fermentation of organic waste. A configuration is disclosed in which the nitrogen content produced and oxidized by the oxidizing action of the strong oxidizing substance is oxidatively decomposed.

Patent Document 2 (Japanese Patent Laid-Open No. 10-85750) discloses a configuration in which seawater containing organic substances is subjected to electrolytic treatment to generate hypochlorous acid.
Thus, the electrolytic treatment is widely used for denitrification treatment in organic wastewater treatment, dephosphorization treatment, deodorization treatment, disinfection / sterilization / bleaching treatment, or seawater electrolysis treatment. As treatment target water, there are many organic wastewaters such as sewage and human waste, water, middle water, seawater, etc., and electrolytic treatment is an important treatment method in water treatment.

As an apparatus configuration of the electrolytic treatment, for example, as described in Patent Document 3 (Japanese Patent Laid-Open No. 2005-279417), an electrolytic chamber that generates active species having a sterilizing ability by electrolyzing raw water with a metal electrode is provided. And the electrolytic chamber is immersed in the water chamber to be treated.
Electrolytic treatment apparatuses include a circulation type that performs electrolytic treatment while circulating water to be treated and a one-through type that performs one-through treatment without circulation.

A circulation type electrolytic treatment apparatus is shown in FIG. This apparatus stores raw water, which is water to be treated, in a circulation tank 70 and supplies it to an electrolytic cell 72 as appropriate by a circulation pump 71. At least a pair of electrodes are immersed in the electrolytic bath 72, and a hypochlorous acid-based material (hereinafter referred to as hypochlorous acid) is generated by supplying electrolysis current from the DC power supply device 73 to the electrodes. . The treated water after the electrolytic treatment is circulated to the circulation tank 70. At this time, since hydrogen gas generated by electrolysis of raw water accumulates in the upper part of the tank, the hydrogen gas is diluted to below the explosion limit by the fan 74 and discharged out of the system.
Next, FIG. 9 shows a one-through type electrolytic treatment apparatus. In this apparatus, raw water is directly supplied to the electrolysis tank 75 by a pump, and hypochlorous acid is generated by supplying electrolysis current in the electrolysis tank 75. The treated water containing hypochlorous acid is stored in the treated water tank 77, where the hydrogen gas is diluted and discharged by the fan 74, and the treated water is also discharged appropriately.

JP 2004-202484 A JP-A-10-85750 JP 2005-279417 A

However, in such an electrolytic treatment apparatus, when a scale component is contained in the water to be treated, there is a problem that the scale adheres to the electrode along with the electrolytic treatment, and the electrolytic efficiency is lowered. Therefore, conventionally, a scale-preventing configuration has been provided, such as periodically removing the scale attached to the electrode by performing a cleaning process, or ensuring the flow velocity on the electrode surface by circulating the water to be treated. In addition, the electrolytic treatment apparatus includes a device such as a fan for diluting hydrogen gas generated by electrolysis.
The electrolytic treatment apparatus is advantageous in that it is small compared to other water treatment apparatuses. On the other hand, as described above, the apparatus is provided with a scale prevention apparatus configuration and a hydrogen gas dilution apparatus configuration. An increase in size is inevitable, and an apparatus configuration that can be further reduced in size has been demanded.
Accordingly, in view of the above-mentioned problems of the prior art, the present invention has an object to provide a water treatment method that has both a scale adhesion preventing function and a hydrogen gas diluting function, and that enables downsizing of the apparatus, and the apparatus. To do.

Therefore, in order to solve such a problem, the present invention electrolyzes water to be treated introduced into an electrolytic cell in the presence of chloride ions, and contains hypochlorous acid containing hypochlorous acid, which is a strong oxidizing substance. In a water treatment method for producing water,
In the previous stage of the electrolytic cell or in the electrolytic cell, the flow rate in the electrolytic cell is ensured, and an amount of air that dilutes the hydrogen gas generated by electrolysis is supplied to the water to be treated. To do.

According to the present invention, by supplying air into the water to be electrolyzed, in addition to the effect of preventing scale adhesion due to the water flow, by blowing air, the flow velocity at the electrode surface is increased and further turbulence is achieved. It is possible to improve the cleaning effect. The blown air can be used as dilution air that has been separately provided for diluting the hydrogen gas generated by the conventional electrolytic treatment to below the explosion limit. Therefore, conventionally, the device for preventing scale adhesion and the device for diluting hydrogen gas are provided separately, but these can be integrated or miniaturized, and the entire device can be miniaturized.
Furthermore, organic chlorine compounds that are produced by hypochlorous acid as a secondary agent can be moved from the liquid phase to the gas phase by mixing bubbles in the circulating liquid, making the treated water harmless. It is possible.

The air is preferably compressed air or microbubbles.
In the present invention, compressed air promotes the generation of water flow, and microbubbles dissipate fine bubbles in water, so that bubbles pass evenly through the electrode surface, and the flow velocity can be increased on any electrode surface. It is possible to increase the scale adhesion preventing effect.

Furthermore, at least a part of the treated water after the electrolytic treatment in the electrolytic bath is circulated through a circulation line inside or outside the bath.
Thus, by circulating the treated water (including the water to be treated), it becomes easier to control the concentration of hypochlorous acid produced, and the flow rate is increased by the circulating flow, which is effective in preventing scale adhesion.
Furthermore, an air lift pump device is provided in the electrolytic tank, and treated water is circulated in the tank.
As described above, by providing the air lift pump device, the flow velocity of the electrode surface can be increased, and in addition to enhancing the effect of preventing scale adhesion, the power for circulation and the power for air supply for diluting hydrogen gas are increased. It can be integrated and power can be reduced.

In addition, a circulation tank that discharges hydrogen gas generated by electrolysis while flowing in water to be treated, and an electrolytic tank that electrolytically treats the water to be treated supplied from the circulation tank via a circulation pump in the presence of chloride ions And a water treatment apparatus comprising a circulation line for circulating at least a part of the treated water discharged from the electrolytic cell to the circulation tank,
An air supply means is provided on the upstream side of the electrolytic cell or in the water to be treated in the electrolytic cell, which supplies air in an amount sufficient to maintain a flow rate in the electrolytic cell and dilute the hydrogen gas. To do.

In addition, an electrolytic tank supplied with water to be treated and electrolytically treated in the presence of chloride ions, a treated water tank for storing treated water discharged from the electrolytic tank and exhausting hydrogen gas generated by electrolysis, In a water treatment device comprising:
An air supply means is provided on the upstream side of the electrolytic cell or in the water to be treated in the electrolytic cell, which supplies air in an amount sufficient to maintain a flow rate in the electrolytic cell and dilute the hydrogen gas. .

Furthermore, in a water treatment apparatus provided with an electrolytic cell in which water to be treated is supplied and electrolytically treated in the presence of chloride ions,
The electrolytic tank includes a tank body and a partition plate that partitions the inside of the tank body into an electrolysis region and a circulation region, and an electrode portion having at least a pair of electrode plates is disposed in the electrolysis region. An air supply means for supplying air in an amount sufficient to secure the flow rate in the tank body and dilute the hydrogen gas is provided below the zone, and the water to be treated circulates between the electrolysis zone and the circulation zone. It is characterized by doing so.

Furthermore, in a water treatment apparatus provided with an electrolytic cell in which water to be treated is supplied and electrolytically treated in the presence of chloride ions,
The electrolytic bath includes a bath body and a partition plate that partitions the inside of the bath body into an electrolysis zone and a circulation zone, and an electrode portion having at least a pair of electrode plates is disposed in the electrolysis zone, and the circulation An air lift pump device is disposed in the region, and the air lift pump device is provided with an air supply means for supplying air in an amount that ensures a flow rate in the tank body and dilutes the hydrogen gas, It is characterized in that the water to be treated circulates between circulation zones.
In these inventions, the air supply means is preferably means for supplying compressed air or microbubbles.

As described above, according to the present invention, it is possible to prevent the scale component from adhering to the electrode, and to provide the effect of diluting the generated hydrogen gas, thereby reducing the size and power of the apparatus.
In other words, in order to ensure the flow velocity (shear flow) on the electrode surface for the purpose of preventing scale adhesion, the scale is prevented from adhering to the anode side by blowing air into the electrolytic cell or water to be treated flowing into the electrolytic cell. In addition to improving the effect and reducing the circulation power, it can be used as dilution air to dilute the hydrogen gas generated on the cathode side to the explosion limit or less due to the electrolytic treatment, and the power of the entire device is almost equal or reduced. While aiming, it is possible to improve the scale adhesion preventing effect.
Furthermore, even with a water treatment method or a water treatment apparatus that does not generate hydrogen on the cathode side, according to the present invention, it is possible to prevent adhesion of scale components to the electrode.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention unless otherwise specified, but are merely illustrative examples. Not too much.
1 is a block diagram showing an outline of a water treatment apparatus according to Embodiment 1 of the present invention, FIG. 2 is a block diagram showing an outline of a water treatment apparatus according to Embodiment 2 of the present invention, and FIGS. FIG. 6 is a block diagram showing an outline of a water treatment apparatus according to Embodiment 4 of the present invention, and FIG. 7 is an electrode to which this embodiment is applied. It is a sectional side view which shows an example of arrangement | positioning.

Examples of water to be treated in this embodiment include waste water such as human waste and sewage, water containing an oxidizable substance, tap water, middle water, and salt-containing water such as seawater.
The purpose of wastewater such as human waste and sewage is to mainly perform denitrification, dephosphorization, deodorization, disinfection, sterilization, bleaching, etc. by electrolytic treatment. The purpose of water containing an oxidizable substance is to oxidatively decompose the oxidizable substance in the water by performing an electrolytic treatment. The purpose of clean water and middle water is to disinfect and sterilize mainly by hypochlorous acid generated by electrolysis by applying electrolytic treatment. Salt-containing water, such as seawater, is mainly subjected to electrolytic treatment to produce hypochlorous acid-containing water, which is used for disinfection, sterilization, bleaching, deodorization, etc., and injected into seawater intakes to the ocean. Used to prevent organisms from attaching.

The basic structure of the electrolytic treatment in this example is to generate hypochlorous acid by electrolyzing the water to be treated in the presence of chloride ions and to be contained in the oxide-containing water by the hypochlorite. It has a structure capable of oxidizing and decomposing an oxide, and further preventing the scale from adhering and diluting hydrogen gas generated by electrolysis.
That is, in order to secure the flow velocity of the electrode surface for the purpose of preventing scale adhesion, air is blown into the water to be treated flowing into the electrolytic cell, thereby improving the scale adhesion preventing effect and reducing the circulation power, as well as the electrolytic treatment. By utilizing the hydrogen gas generated as a result of dilution air that dilutes to below the explosion limit, the scale adherence prevention effect can be improved while the power of the entire apparatus is substantially equal or reduced.
Examples 1 to 4 below show specific water treatment methods and apparatuses.

As shown in FIG. 1, the first embodiment is a circulation type device, and includes a circulation tank 10 into which raw water 20 flows, an electrolytic cell 13 connected to the circulation tank 10 by a line 21, and the line 21. The circulation pump 11 and the DC power supply device 14 for supplying a current for electrolysis to the electrode plate immersed in the electrolytic cell 13 are provided, and the treated water 25 discharged from the electrolytic cell 13 is supplied to the circulation tank 10. A discharge line 24 for discharging the treated water to the outside of the system, and a three-way valve 15 for switching the treated water circulation line. Moreover, the fan 16 which supplies air with respect to the gaseous phase of the circulation tank 10 is provided as needed.
One or more circulation tanks 10 are provided. The circulation tank 10 has a function of temporarily storing raw water or treated water in principle, but may be provided with chloride ion addition means, pH adjustment means, and the like as necessary. These chloride ion adding means, pH adjusting means and the like may be provided on the electrolytic cell 13 side.

One or a plurality of electrolytic cells 13 are provided. The electrolytic tank 13 includes a tank body and at least a pair of electrode plates immersed in the raw water in the tank body, and a direct current power supply device 14 connected to the electrode plates supplies an electrolysis current to the electrode plates. By supplying, the electrolytic reaction of the water to be treated is performed.
A plurality of electrode plates may be arranged. In this case, for example, the apparatus configuration shown in FIG. 7 can be used. As shown in the same figure, it has a cathode energizing rod 62 installed on the raw water inlet side of the tank body 65 and an anode energizing rod 63 installed on the outlet side, and between these energizing rods 62, 63. A plurality of electrode plates 61 are arranged. The electrode plates 61 are arranged in multiple stages in a staggered manner in parallel with the flow of raw water in the tank body 65. The blackened portion of each electrode plate becomes the anode. The raw water flows through the tank body 65 and a current flows from the anode energizing rod 63 to the cathode energizing rod 62, whereby the raw water is sequentially electrolyzed by the electrode plates 61 of each stage.

  Further, as a characteristic configuration of the present embodiment, for the purpose of preventing adhesion of scale components and diluting hydrogen gas, an air supply means for blowing air into the raw water at the front of the electrolytic cell 13 or the electrolytic cell 13 is provided. In FIG. 1, a compressor 12 for supplying compressed air is provided on a raw water line 21 from the circulation tank 10 to the electrolytic cell 13. The compressor 12 feeds air into the raw water flowing into the electrolytic cell 13 and electrolyzes the raw water containing bubbles in the electrolytic cell 13. The compressor 12 may be installed anywhere as long as it is between the circulation tank 10 and the electrolytic cell 13, but is preferably provided downstream of the circulation pump 11 and upstream of the electrolytic cell 13. This is to prevent a problem that occurs when a large amount of air bubbles enter the circulation pump 11.

By blowing air into the raw water, the flow velocity of the electrode surface in the electrolytic cell 13 increases, further turbulence occurs on the electrode surface, the scale does not easily adhere to the electrode, and the scale of the attached scale Has a cleaning effect.
Furthermore, the presence of bubbles in the treated water makes it possible to reduce the circulation power in the circulation pump 11.
Furthermore, the hydrogen gas generated in the electrolytic tank 13 by the electrolytic treatment is accumulated in the gas phase of the circulation tank 10, and the air blown by the compressor 12 is accumulated in the gas phase together with the hydrogen gas. Diluted. Accordingly, the fan 16 can be omitted, or the fan 16 can be reduced in size or power can be reduced.

  In this embodiment, the compressor for supplying compressed air is exemplified as the air supply means. However, the present invention is not limited to this. Means for supplying normal air such as a blower, means for supplying microbubbles, etc. Also good. Microbubbles are fine bubbles having a diameter of 10 to 500 μm. The advantage of using microbubbles is that fine bubbles diffuse in water, so even if multiple electrodes are provided, they pass through the electrode surface almost evenly, and the flow velocity can be increased on any electrode surface. It is effective in preventing adhesion.

  The operation of the apparatus shown in FIG. 1 will be described. First, raw water stored in the circulation tank 10 is appropriately fed to the electrolytic cell 13 via the line 21 by the circulation pump 11. At this time, compressed air is blown into the raw water of the line 21 by the compressor 12. The raw water containing bubbles flows into the electrolytic cell 13 and is electrolyzed in the electrolytic cell 13.

As an example, the reaction in electrolytic treatment is shown below together with the type of raw water and the content of the treatment.
When seawater is electrolyzed to produce sodium hypochlorite, the following reaction is obtained by electrolysis.
2Cl ⁻ → Cl ₂ + 2e
2H ₂ O + 2e → 2OH− + H ₂
2Na ⁺ + 2OH ⁻ → 2NaOH
Chlorine (Cl ₂ ) generated at the anode reacts with sodium hydroxide (NaOH) generated at the cathode, and sodium hypochlorite (NaClO) is generated by the following reaction.
Cl ₂ + 2NaOH → NaClO + NaCl + H ₂ O
The sodium hypochlorite-containing water produced in this way is supplied to seawater intakes and pipes, condensers, parts that come in contact with seawater, such as various coolers, so that marine organisms such as algae and shellfish It is possible to prevent adhesion.

As another example, when organic nitrogen waste water is electrolyzed for denitrification, the following reaction is obtained by electrolysis.
H ₂ O → 1 / 2O ₂ + 2H ⁺ + 2e ⁻
2Cl ⁻ → Cl ₂ + 2e ⁻
Cl ₂ + H ₂ O → HClO + HCl
H ₂ O + e ⁻ → 1 / 2H ₂ + OH ⁻
Thereby, hypochlorous acid (HClO) having very strong oxidizing power is generated. This hypochlorous acid reacts with ammonia in wastewater, and is converted into harmless nitrogen gas by the following reaction.
2NH ₃ + 3HClO → N ₂ + 3HCl + 3H ₂ O
In addition, by the electrolytic treatment of this configuration, dephosphorization treatment, disinfection / sterilization / bleaching treatment, and other electrolytic treatment are possible.

The treated water after the electrolytic treatment is discharged from the electrolytic cell 13 through the line 22 and returned to the circulation tank 10 through the circulation line 23. In the circulation tank 10, hydrogen gas generated by the electrolytic reaction accumulates on the gas phase side, and if necessary, air is supplied by a fan 16 to dilute to the explosion limit or less and then discharged as exhaust gas 26. At this time, since air is supplied in advance by the compressor 12, it is not necessary to supply dilution air if the hydrogen gas is sufficiently diluted.
The treated water returned to the circulation tank 10 is supplied to the electrolytic tank 13 and the electrolytic treatment is repeatedly performed. At this time, the operation time of the electrolytic cell 13 may be measured, and the three-way valve 15 may be operated based on the operation time and circulated for a predetermined time, and then the treated water may be discharged by switching the circulation line. Alternatively, a part of the treated water from the electrolytic bath 13 may be drawn and circulated, the other treated water may be discharged, and the raw water 20 may be added to the circulated treated water for electrolytic treatment.

According to the present embodiment, turbulence is generated by supplying air into the water to be electrolyzed, and in addition to the effect of preventing scale adhesion due to this water flow, the cleaning effect on the electrode surface is improved by blowing air. It is possible to make it. The blown air can be used as dilution air that has been separately provided for diluting the hydrogen gas generated by the conventional electrolytic treatment to below the explosion limit. Therefore, conventionally, the device for preventing scale adhesion and the device for diluting hydrogen gas are provided separately, but these can be integrated or miniaturized, and the entire device can be miniaturized.
Furthermore, organic chlorine compounds that are produced by hypochlorous acid can be moved from the liquid phase to the gas phase by mixing bubbles in the circulating liquid, facilitating gas-liquid separation. It is possible to render the treated water harmless.

FIG. 2 shows a water treatment apparatus according to the second embodiment. In the following second to fourth embodiments, detailed description of the same configurations as those of the first embodiment will be omitted.
This apparatus is a one-through type apparatus, and supplies a current for electrolysis to a pump 26 provided on a line 27 for feeding the raw water 20, an electrolytic bath 17 for electrolyzing the raw water 20, and electrodes of the electrolytic bath 17. A DC power supply device 18, a treated water tank 19 to which treated water from the electrolytic cell 17 is supplied via a line 28, and a pump 29 for discharging treated water 25 stored in the treated water tank 19. . Moreover, the fan 16 which supplies the air for hydrogen gas dilution to the treated water tank 19 is provided as needed.
Further, as a characteristic configuration of the present embodiment, an air supply means for blowing air into the water to be treated is provided in the electrolytic cell 16 or in the previous stage thereof. In the present embodiment, a compressor 12 that supplies compressed air is provided upstream of the electrolytic cell 17.

The operation of this apparatus will be described. Raw water 20 is supplied to the electrolytic cell 17 by the pump 26 and air is blown into the raw water 20 by the compressor 12. The raw water 20 containing bubbles is subjected to electrolytic treatment by the electrolytic bath 17. Here, the electrolysis is performed by a one-through treatment, and the electrolytic treatment may be performed in the electrolytic bath 17 for a predetermined time, or the end time of the electrolysis may be determined based on an index such as pH or ORP in the treated water.
The treated water discharged after the electrolytic treatment is stored in the treated water tank 19. The hydrogen gas accumulated on the gas phase side in the treated water tank 19 is diluted by the air supplied by the compressor 12 and is discharged as the exhaust gas 26 after supplying the dilution air by the fan 16 as necessary. . The treated water 25 is appropriately discharged by a pump 29.

According to the present embodiment, since electrolysis is a one-through treatment, the conventional apparatus did not secure a water flow and the scale was easy to adhere.However, as in this configuration, the scale adhesion was prevented by blowing air into the water to be treated. The cleaning effect on the electrode surface can be improved.
Furthermore, since the blown air also has the effect of diluting the hydrogen gas as in the first embodiment, it is not necessary to provide a dilution fan, or the fan can be downsized, and the entire apparatus can be downsized. Furthermore, organic chlorine compounds that are produced by hypochlorous acid as a secondary agent can be moved from the liquid phase to the gas phase by mixing bubbles in the circulating liquid, thereby promoting gas-liquid separation. It is possible.

3 to 5 show a water treatment apparatus according to the third embodiment. The third embodiment has a circulation type and an apparatus integrated type configuration.
First, referring to FIG. 3, this apparatus 30A includes a tank main body 31, a raw water inlet 31a provided below the side of the tank main body 31, and a treated water provided below the side facing the raw water inlet 31a. A partition plate 32 that partitions the tank body 31 so as to divide the outlet 31b, the raw water inlet 31a and the treated water outlet 31b, an electrolysis region 34 formed on the raw water inlet 31a side by the partition plate 32, and a treated water outlet 31b And a circulation zone 35 formed on the side.

The partition plate 32 is open at the top and bottom, and the electrolysis zone 34 and the circulation zone 35 communicate at the top and bottom.
In the electrolysis region 34, an electrode portion 36 on which an electrode plate is disposed is disposed. A pair or a plurality of electrode plates are disposed on the electrode portion 36, and the electrode plates are connected to a DC power supply device (not shown).

  Furthermore, as a characteristic configuration of the present embodiment, an air supply means for blowing air from below the electrolysis zone 34 is provided. In this embodiment, a compressor 45 for supplying compressed air is provided, and the compressed air 42 is supplied from the air blowing port 33 by the compressor 45. The air supply means can employ other configurations as in the first embodiment.

Explaining the operation of this apparatus, the raw water 40 supplied into the tank body 31 from the raw water inlet 31a flows through the electrolysis region 34 in accordance with the upward flow formed by the compressed air supplied from the compressor 45, and flows to the electrode part 36. To be electrolyzed. The hydrogen gas generated by the electrolysis moves to the gas phase side above the tank body 31 together with the air supplied from the compressor 45, is further diluted by the air 48 blown as necessary, and is discharged as the exhaust gas 47.
On the other hand, the treated water after the electrolytic treatment overflows the upper part of the partition plate 32 and flows into the circulation zone 35. In the circulation zone 35, a downward flow is formed, and the treated water circulates from the lower part of the partition plate 32 to the electrolysis zone 34. Thus, in this apparatus, the circulation flow shown by the arrow in the figure is formed.
When the electrolytic treatment is completed, the treated water 41 is discharged from the treated water outlet 31b.

  In the present embodiment, in addition to the effect of supplying air as described in the first embodiment, a circulation flow is formed in one tank body to form an integrated apparatus configuration. Miniaturization is possible and there is no need to provide a circulation device such as a circulation pump. This apparatus can be suitably applied when the amount of water to be treated for electrolytic treatment is small.

Further, FIG. 4 shows an apparatus to which FIG. 3 is applied. In the apparatus 30B of the present embodiment, an air lift pump device 37 is provided in addition to the apparatus configuration shown in FIG.
The air lift pump device 37 includes an air lift pipe 35 extending in a direction perpendicular to the circulation area 35, means for supplying air 43 from the bottom of the air lift pipe 35, and processing from the upper part of the electrolysis area 34 to the lower part of the air lift pipe 35. And a circulation line 39 for introducing water.
The raw water inlet 31 a is provided in the upper part of the circulation area 35, and the treated water outlet is provided in the lower part of the circulation area 35. Further, similarly to FIG. 3, a compressor 45 for supplying air from the lower part of the electrolysis zone 34 is provided.

In the present embodiment, an upward flow is formed in the air lift pipe 38 by the supply of air 43, and a downward flow is formed around the air lift pipe 38. This downward flow is directed from the lower communicating portion of the partition plate 32 toward the electrolysis zone 34, and an upward flow is formed in the electrolysis portion 34. Further, the treated water electrolyzed by the electrode part 36 of the electrolysis part 34 is supplied to the lower part of the air lift pipe 38 via the circulation line 39.
Thus, by providing the air lift pump device 37, the flow rate of the circulating flow is increased, and further, the scale adhesion preventing effect is improved in combination with the increase of the flow rate due to the air blowing by the compressor 45.

  Furthermore, FIG. 5 shows another apparatus to which FIG. 3 is applied. The apparatus 30C of the present embodiment is configured such that the compressor 45 is not installed in the apparatus configuration shown in FIG. As described above, even when the compressor 45 is not installed, scale adhesion prevention and hydrogen gas dilution can be achieved at the same time by forming a circulating flow by the air lift pump device 37 and blowing in the air 43. According to this embodiment, since the compressor is not installed, it is possible to reduce power, simplify the apparatus, and reduce the size.

FIG. 6 shows a water treatment apparatus according to the fourth embodiment. The fourth embodiment has a circulation type and an apparatus integrated type configuration.
The apparatus 50 includes a tank body 51, a raw water inlet 31 a provided at a side of the tank body 51, an electrolysis zone 57 having the raw water inlet 31 a and formed by a partition plate 55, and the electrolysis zone 57. The electrode part 52 arranged horizontally at a position separated from the raw water inlet 31a, the air lift pump device 53 arranged between the raw water inlet 31a and the electrode part 52, and the treated water that has passed through the electrode part 52 From the circulation line 56 supplied to the lower part of the air lift pump device through the side and bottom of the tank body 51, and the treated water outlet 31b provided on the downstream side of the circulation line 56. Composed.

The lower part of the air lift pipe 54 of the air lift pump device 53 communicates with the circulation line 56 and the upper part is opened, so that treated water flows from the upper opening of the air lift pipe 54 to the front of the electrode part 52. The treated water that has flowed in from the raw water 40 or the air lift pipe 54 passes through the electrode portion 52 in the direction of the arrow in the figure, and after being subjected to electrolytic treatment, overflows the partition plate 55 and flows into the circulation line 56. 56 is moved in the direction of the arrow in the figure and introduced into the lower part of the air lift pipe 54. Air 43 is supplied to the air lift pipe 54 to form the above-described circulation flow.
In this apparatus, after the raw water 40 is supplied, it is circulated for a predetermined time and subjected to electrolytic treatment, and then discharged as treated water 41. Alternatively, the raw water 40 is subjected to electrolytic treatment while supplying a predetermined amount from the raw water inlet 31a. A circulating operation may be performed by extracting a predetermined amount from the treated water outlet 31b.

  According to the present embodiment, in addition to the effect of supplying air as described in the first embodiment, a circulation flow is formed in one tank body, and an integrated apparatus configuration is formed. Miniaturization is possible and there is no need to provide a circulation device such as a circulation pump. This apparatus can be suitably applied when the amount of processing is small. Further, in the present embodiment, unlike the third embodiment, the circulation line 56 is incorporated in the tank body 51, so that the apparatus configuration can be simplified.

It is a block diagram which shows the outline of the water treatment apparatus which concerns on Example 1 of this invention. It is a block diagram which shows the outline of the water treatment apparatus which concerns on Example 2 of this invention. It is a block diagram which shows the outline of the water treatment apparatus which concerns on Example 3 of this invention. It is a block diagram which shows the outline of the water treatment apparatus to which FIG. 3 is applied. It is a block diagram which shows the outline of the other water treatment apparatus to which FIG. 3 is applied. It is a block diagram which shows the outline of the water treatment apparatus which concerns on Example 4 of this invention. It is a sectional side view which shows an example of electrode arrangement | positioning to which a present Example is applied. It is a block diagram of the conventional water treatment apparatus. It is a block diagram of the conventional water treatment apparatus different from FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Circulation tank 11 Circulation pump 12 Compressor 13, 17 Electrolysis tank 14, 18 DC power supply device 19 Treated water tank 23, 39, 56 Circulation line 31, 51 Tank main body 32, 55 Partition plate 34 Electrolysis area 35 Circulation area 36, 52 Electrode Part 37, 53 Air lift pump device 38, 54 Air lift pipe

Claims (9)

In the water treatment method of generating hypochlorous acid-containing water containing hypochlorous acid, which is a strong oxidizing substance, by subjecting the water to be treated introduced into the electrolytic cell to electrolytic treatment in the presence of chloride ions,
In the previous stage of the electrolytic cell or in the electrolytic cell, the flow rate in the electrolytic cell is ensured, and an amount of air that dilutes the hydrogen gas generated by electrolysis is supplied to the water to be treated. Water treatment method.   The water treatment method according to claim 1, wherein the air is compressed air or microbubbles.   The water treatment method according to claim 1 or 2, wherein at least a part of the treated water after electrolytic treatment in the electrolytic bath is circulated through a circulation line inside or outside the bath.   The water treatment method according to claim 1 or 2, wherein an air lift pump device is provided in the electrolytic tank, and the treated water is circulated in the tank. A circulation tank that discharges hydrogen gas generated by electrolysis and into which the water to be treated flows, and an electrolytic tank that electrolytically treats the water to be treated supplied from the circulation tank through a circulation pump in the presence of chloride ions; In a water treatment apparatus comprising a circulation line for circulating at least a part of the treated water discharged from the electrolytic cell to the circulation tank,
An air supply means is provided on the upstream side of the electrolytic cell or in the water to be treated in the electrolytic cell, which supplies air in an amount sufficient to maintain a flow rate in the electrolytic cell and dilute the hydrogen gas. Water treatment equipment. An electrolytic bath for supplying water to be treated and electrolytically treating in the presence of chloride ions, and a treated water tank for storing treated water discharged from the electrolytic bath and exhausting hydrogen gas generated by electrolysis are provided. Water treatment equipment,
An air supply means is provided on the upstream side of the electrolytic cell or in the water to be treated in the electrolytic cell, which supplies air in an amount sufficient to maintain a flow rate in the electrolytic cell and dilute the hydrogen gas. Water treatment equipment. In a water treatment apparatus equipped with an electrolytic tank for supplying water to be treated and electrolytically treating in the presence of chloride ions,
The electrolytic tank includes a tank body and a partition plate that partitions the inside of the tank body into an electrolysis region and a circulation region, and an electrode portion having at least a pair of electrode plates is disposed in the electrolysis region. An air supply means for supplying air in an amount sufficient to secure the flow rate in the tank body and dilute the hydrogen gas is provided below the zone, and the water to be treated circulates between the electrolysis zone and the circulation zone. A water treatment apparatus characterized by having made it. In a water treatment apparatus provided with an electrolytic cell that is supplied with water to be treated and performs electrolytic treatment in the presence of chloride ions,
The electrolytic bath includes a bath body and a partition plate that partitions the inside of the bath body into an electrolysis zone and a circulation zone, and an electrode portion having at least a pair of electrode plates is disposed in the electrolysis zone, and the circulation An air lift pump device is disposed in the region, and the air lift pump device is provided with an air supply means for supplying air in an amount that ensures a flow rate in the tank body and dilutes the hydrogen gas, A water treatment apparatus characterized in that water to be treated circulates between circulation zones.   The water treatment apparatus according to any one of claims 5 to 8, wherein the air supply means is means for supplying compressed air or microbubbles.

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