JP2000005755A - Treatment of water and device therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stabilize high bacteriostatic performance and to enable to keep the performance over a long period of time by adding continuously or intermittently hydrogen peroxide to a water to be treated and passing the water to be treated through a fixed bed type three-dimensional electrode electrolytic cell. SOLUTION: A hydrogen peroxide adding part 40 composed of a hydrogen peroxide water tank 41, its sending pump 42 and a valve 43 is provided at a water treating device 100 and a water storage tank 51 is provided. The water to be treated in the water storage tank 51 is sent with the pump 52 and passed through a filter 53 while being added in the process the hydrogen peroxide water at the hydrogen peroxide adding part 40, and passed through the fixed bed type three-dimensional electrode electrolytic cell 20, and a water to be treated in the electrolytic cell 20 is returned again to the water storage tank 51 to form a circuit of the water to be treated. Then after starting the device, the water to be treated in the water storage tank 51 is subjected to sterilizing treatment at short time, and also its state is kept over a long period of time. In this way, a clogging due to an org. matter is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water treatment method and a water treatment apparatus using a fixed-bed type three-dimensional electrode electrolytic cell for electrochemically treating treated water, for example, treated water containing microorganisms or organic substances. About.

[0002]

2. Description of the Related Art Pure water and industrial water are used in various manufacturing industries. Since various organic substances are mixed in the water used in the washing process, this provides an appropriate nutrient, and when the liquid temperature of the aqueous solution reaches a temperature suitable for the propagation of microorganisms, microorganisms such as bacteria grow and the product is reduced. It causes performance degradation and floats or accumulates in the treatment equipment, making it difficult to reuse water.

[0003] For example, in the production of semiconductors or printed circuit boards, a large amount of pure water or ultrapure water is used in a cleaning step. Since it is costly to make pure water or ultrapure water from industrial water, washing wastewater is usually recycled and used. However, microorganisms such as bacteria proliferate due to organic substances and the like brought in from the washing step, thereby deteriorating the performance of the product and increasing the load on the regeneration step.

[0004] In recent years, with the increase of buildings such as condominiums and other condominiums or buildings formed by gathering a large number of companies, the number of various types of cooling and heating equipment installed in the buildings and the like has also increased. Are increasing. In condominiums, buildings, and the like in which such a large number of cooling and heating facilities are installed, equipment for heat exchangers for cooling water of the cooling and heating equipment, such as a cooling tower, is usually installed on the roof.
If the cooling water of this heat exchanger equipment is also used for a long period of time, microorganisms such as molds and bacteria will propagate and precipitate on the heat exchange surface of the heat exchanger to deteriorate the heat exchange performance, or the microorganisms will be generated in a lump. In some cases, piping and the like may be blocked. In addition, serious problems such as corrosion may occur in piping and equipment due to a large amount of microbial waste generated.

As a water treatment method for eliminating the above-mentioned disadvantages, there is a method of electrochemical treatment, which is disclosed in, for example, JP-A-3-224686 and JP-A-4-27488. According to this method, a large amount of water can be efficiently treated.

[0006]

However, in these methods, when the water to be treated contains a high concentration of organic matter, the flow rate may be reduced due to clogging of the electrolytic cell, and the treatment efficiency may be reduced. The improvement was desired.
The object of the present invention is to solve such problems and stabilize high bacteriostatic performance using a fixed-bed type three-dimensional electrode electrolytic cell even when the water to be treated contains a high concentration of organic matter. To provide a water treatment method and apparatus which can be maintained for a long period of time.

[0007]

This object is achieved by any of the following technical means (1) to (6).

(1) In a water treatment method using a fixed-bed type three-dimensional electrode electrolytic cell in which water to be treated is passed through a fixed-bed type three-dimensional electrode electrolytic cell and electrochemically treated, the water to be treated is excessively treated. A water treatment method comprising adding hydrogen oxide continuously or intermittently, and treating the water to be treated by passing the water through a fixed-bed type three-dimensional electrode electrolytic cell.

(2) The water treatment method according to item (1), wherein the concentration of the hydrogen peroxide added in the addition section is 1 to 10000 ppm with respect to the water to be treated.

(3) During the water treatment period, the average addition amount of the hydrogen peroxide in the addition section is 24 to 10000 ppm · h.
r / day, the water treatment method according to the above mode (1) or (2).

(4) The water to be treated has an electric conductivity of 30 μm.
The water treatment method according to any one of (1) to (3), wherein the water is pure water of S / cm or less or pure water recycled water.

(5) The water to be treated is passed through a fixed-bed type three-dimensional electrode electrolytic cell to be treated electrochemically in a water treatment apparatus using a fixed-bed type three-dimensional electrode electrolytic cell. A water treatment apparatus comprising means for continuously or intermittently adding hydrogen oxide.

(6) The means for continuously or intermittently adding the hydrogen peroxide performs at least a hydrogen peroxide water tank and a constant supply from the tank in a supply pipe of the water to be treated to the electrolytic cell. The water treatment apparatus according to item (5), comprising a liquid feed pump.

Hereinafter, the present invention will be described in detail.

In the electrolytic cell used in the present invention, one or more generally three or more fixed-bed type three-dimensional electrodes are accommodated in a cylindrical container in a non-contact state, and both ends are supplied with external voltage. Is a carbonaceous fixed-bed type three-dimensional bipolar electrolytic cell in which power supply electrodes are arranged. When a plurality of fixed-bed type three-dimensional electrodes are used, they are of a bipolar type, and the fixed-bed type three-dimensional electrodes are generally made of carbon. For this reason, the carbonaceous fixed bed type three-dimensional bipolar electrolytic cell may be referred to as a carbonaceous fixed bed type three-dimensional electrode electrolytic cell or simply a fixed bed type three-dimensional electrode electrolytic cell or simply an electrolytic cell. Further, the carbonaceous fixed bed may be simply referred to as a fixed bed. By applying a voltage to the power supply electrode, each fixed-bed type three-dimensional electrode is polarized, and the water to be treated can pass therethrough. When the water to be treated is supplied to the fixed-bed type three-dimensional electrode electrolytic cell, the microorganisms in the water to be treated come into contact with or adsorb to the carbonaceous fixed-bed type three-dimensional electrode or the power supply electrode of the electrolytic cell due to the liquid flow. It is thought that a strong redox reaction or contact with a high-potential electrode occurs on the surface of, and its activity is weakened or kills itself and sterilization is performed.

The fixed-bed type three-dimensional electrode used in the electrolytic cell is preferably a porous electrode material made of carbonaceous material. Carbon materials tend to adsorb microorganisms such as bacteria, and the activity can be reduced or sterilized by applying a voltage to the adsorbed or trapped microorganisms. On the other hand, it was clarified that when the water to be treated contained organic substances, they adhered to the electrode surface, hindered the adsorption of bacteria, and as a result, sterilization performance was reduced.

Therefore, as a result of diligent studies to solve this problem, hydrogen peroxide was added to the water to be treated, and this was treated in an electrolytic bath, whereby the dead matter of organic substances or microorganisms attached to the electrode surface was removed. Was found to be able to be removed, and higher bacteriostatic performance could be maintained over a long period of time. This is because organic substances are oxidized by hydrogen peroxide,
It is presumed that the attached foreign matter is peeled off by the fine oxygen gas generated by the catalytic action of the platinum used as the auxiliary electrode.

The concentration of hydrogen peroxide to be added is 1 to
It is preferably contained at a concentration of 10,000 ppm, may be added continuously at a low concentration, or may be added intermittently at a relatively high concentration, and
pm · hr / day.

A predetermined voltage can be applied to the electrolytic cell even during the addition of hydrogen peroxide to the water to be treated.

A preferred method of treating the water to be treated using this apparatus is to send the water to be treated from the water storage tank to the present electrolytic cell,
In a circulation treatment system for returning to the water storage tank, it is desirable to provide a hydrogen peroxide addition unit upstream of the water storage tank or the electrolytic tank. The added hydrogen peroxide is decomposed into water and oxygen by the catalytic action of platinum used as an auxiliary electrode when passing through the electrolytic cell, but if the remaining hydrogen peroxide hinders the use of treated water, A hydrogen peroxide decomposer using a catalyst such as platinum can be provided on the piping route to the point of use.

The method of adding hydrogen peroxide is achieved by preparing a high-concentration aqueous solution of hydrogen peroxide in a tank and adding a certain amount of the aqueous solution to the water to be treated using a pump or the like. The method is not limited. Further, the addition can be carried out intermittently using a timer or the like, or the addition amount can be changed according to the degree of water contamination.

The voltage is applied to the electrolytic cell when the anode potential is +
0.2 to +1.2 V (vs. SCE), cathode potential is 0 to
It is desirable that the voltage be −1.0 V (vs. SCE). However, when an undesirable change in liquid properties does not occur due to the influence of substances in the liquid or when the reaction amount does not matter, the anode potential is increased by +2. 0.0V (vs. SHE) or more,
The cathode potential can be set to a potential of -2.0 V (vs. SHE) or less.

In the case of reforming the water to be treated, particularly when a large amount of water such as pool water or paper washing water is generated and gas is generated,
The generated gases, that is, oxygen gas and hydrogen gas, are usually generated at a mixing ratio within the explosion limit, and it is desirable to dilute with an inert gas such as air to avoid the danger of explosion. A gas separating means and a means for diluting the separated electrolytic gas with air so that the electrolytic gas concentration becomes 4% by volume or less can be provided.

The electrodes in the carbonaceous fixed bed type three-dimensional electrode electrolytic cell of the present invention generally include a fixed bed type three-dimensional electrode and a power supply electrode, and the fixed bed type three-dimensional electrode corresponds to the above-mentioned electrolytic cell used. A porous material having a shape and through which the water to be treated can permeate, for example, a granular material, a spherical shape, a felt shape, a woven fabric shape, a carbon-based material such as a porous block shape, activated carbon, graphite, and carbon fiber. Or a plurality of preferably granular, spherical, fibrous, felt made of a metal material having the same shape, such as nickel, copper, stainless steel, iron, titanium, or the like, and a material obtained by applying a noble metal coating to the metal material. The fixed bed may be a shape, a woven fabric, a porous block, or a sponge-like dielectric.

The plurality of stacked fixed beds are accommodated in a cylindrical body having both ends open as fixed bed type three-dimensional electrodes.
The tubular body is preferably formed of an electrically insulating material that can withstand long-term use or re-use. In particular, synthetic resins such as polyepichlorohydrin, polyvinyl methacrylate, polyethylene, polypropylene, polyvinyl chloride, and poly (ethylene chloride) , Phenol-formaldehyde resin, ABS resin, acrylic resin and the like. Further, it is more convenient to use a transparent or translucent material because the state of consumption of the carbonaceous fixed bed can be visually recognized.

Since the diameter of the plurality of carbonaceous fixed beds accommodated in the tubular body is equal to or slightly smaller than the inner diameter of the tubular body, only the tubular body is gripped to fix the carbonaceous fixed bed. When an operation such as replacement of the floor is performed, the fixed carbonaceous bed separates from one opening, and a predetermined number of fixed carbonaceous beds cannot be accommodated in the cylindrical body.

Therefore, in the electrolytic cell according to the present invention, a support is provided so as to close a part of one opening of the tubular body, and the carbonaceous fixed bed is detached, that is, dropped from the tubular body. Is preferably prevented. The shape of the support is not particularly limited as long as it has sufficient strength to suppress the movement of the plurality of carbonaceous fixed beds, and a donut-shaped body (ring) is attached to the lower end of the cylindrical body. A ring or the like is fixed by welding, bonding, or the like so as to cover a part of the opening, or a part having the same shape as the donut-shaped body (ring) is integrally molded with the cylindrical body, or a cross-shaped member is formed. It can be fixed by bonding or the like so as to straddle the circumferential portion at the lower end of the cylindrical body, or a mesh body can be similarly installed in the closed portion.
Further, a screw may be engraved on the donor-shaped body and the cylindrical body, and both members may be screwed and fixed to each other. Similarly, the other side of the opening can be provided with a support by screwing, so that the carbonaceous fixed bed can be accommodated in the tubular body in a more stable state.

The cross-sectional area of the support perpendicular to the flow direction of the water to be treated is desirably 3 to 50% of the opening area of the opening. Detachment from the tubular body is apt to occur, and if it exceeds 50%, the flow of the water to be treated is hindered and the electrolysis voltage tends to increase.

The carbonaceous fixed bed is placed in a DC or AC electric field, and a DC voltage or AC voltage is applied between power supply electrode terminals formed of a perforated plate such as a lithographic plate, expanded mesh, or perforated plate provided at both ends. A carbonaceous fixed bed type tertiary containing a fixed bed type three-dimensional electrode formed by applying a voltage to polarize the carbonaceous fixed bed and forming an anode and a cathode at one end and the other end of the carbonaceous fixed bed by polarization, respectively. In addition, a fixed-bed type three-dimensional electrode functioning independently as an anode or cathode can be installed so as not to be short-circuited alternately, and electrically connected to form a carbonaceous cell. It can be a fixed-bed three-dimensional bipolar electrolytic cell.

Examples of the material for the power supply anode include a carbon graphite material (carbon fiber, carbon cloth, graphite, etc.), a carbon composite material (a material obtained by mixing a metal in powder form with carbon and sintering, etc.), an activated carbon fiber nonwoven fabric. (Eg KE-
1000 felt, Toyobo Co., Ltd.) or platinum,
There are materials supporting palladium, nickel, and the like, as well as materials formed from dimensionally stable electrodes (platinum group oxide-coated titanium materials), platinum-coated titanium materials, nickel materials, stainless steel materials, iron materials, and the like. Further, the power supply cathode terminal that faces the power supply anode terminal and applies a negative DC voltage is, for example, platinum, stainless steel, titanium, nickel, copper, hastelloy,
It can be formed from graphite, a carbon material, a mild steel or a metal material coated with a platinum group metal.

When a carbonaceous material such as activated carbon, graphite, or carbon fiber is used as the carbonaceous fixed bed and water to be treated is treated while generating oxygen gas from the anode,
The carbonaceous fixed bed is oxidized by oxygen gas and easily dissolved as carbon dioxide gas. In order to prevent this, the carbonaceous fixed bed is usually used as an insoluble metal electrode in which a platinum group metal oxide such as iridium oxide and ruthenium oxide or platinum is coated on a base material such as titanium on the side of positive polarization of the carbonaceous fixed bed. It is desirable to place the porous or reticulated material in contact so that oxygen evolution occurs primarily on the material.

If there is a gap in the electrolytic cell through which the water to be treated flows, through which the liquid can flow without contacting the fixed carbonaceous bed, the treatment efficiency of the treated water is reduced. It is desirable to arrange the flow of the water to be treated in the electrolytic cell so as not to cause a short path.

The flow rate of the water to be supplied to the electrolytic cell may be determined so that the water to be treated can efficiently contact the surface of the electrode or the like. Because there is less movement and less contact with the carbonaceous fixed bed surface,
Preferably, a turbulent state is formed, 500
It is particularly preferable to use a turbulent flow having the above Reynolds number.

When the anode chamber and the cathode chamber are formed by partitioning the inside of the electrolytic cell with a diaphragm, electricity can be supplied without using a diaphragm. However, a carbonaceous fixed bed (carbon) can be used without using a diaphragm. When the distance between the electrodes of the fixed bed type three-dimensional electrode) or the distance between the carbonaceous fixed bed and the power supply electrode is reduced, the flow of the water to be treated is made of an electrically insulating material such as a donut to prevent a short circuit. A mesh-like spacer made of, for example, an organic polymer material, which does not hinder, can be inserted between the carbonaceous fixed beds and between the carbonaceous fixed beds and the power supply electrodes. When a diaphragm is used, it is porous so as not to hinder the movement of the water to be circulated.
It is desirable to use the thing of 0% or more and 80% or less,
The diaphragm must have at least micropores with a pore size that allows the water to be treated to permeate.

In the electrolytic cell used in the present invention, a positive electrode and a negative electrode in the electrolytic cell are used in order to prevent a leakage current from occurring in the electrolytic cell and electrochemically corrode a pump or other equipment through the water to be treated. A member having a higher conductivity than the liquid to be treated can be installed in the back surface of the electrode and / or in the inlet / outlet pipe of the electrolytic cell so that one end of the member can be grounded, and the leakage current can be cut off.

The water treatment method of the present invention can be particularly preferably used in a regeneration step in recycling pure water or ultrapure water washing wastewater used in semiconductors, printed circuit boards and various other manufacturing industries. Particularly, in recent years, pure water has been used for washing in various manufacturing processes for effective use of water resources, and most of them are reused after activated carbon treatment, ion exchange treatment and the like again. However, the recycling process is subject to microbial contamination,
Microorganisms and their dead bodies may cause product defects. Recycled water is in an environment where it becomes eutrophic due to organic matter brought in from the washing process and microorganisms can easily propagate. The water treatment method of the present invention is particularly suitable for treating such pure water used for industrial purposes and its recycled water.

Alternatively, the water to be treated, such as a heat exchanger, a gas scrubber, or a paper making process, which is installed on the roof of a building or an apartment, is introduced into the electrolytic cell and electrochemically treated so as to be treated. A reforming treatment such as sterilization of treated water can also be performed.

[0038]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred example of a fixed-bed type three-dimensional electrode electrolytic cell according to the present invention will be described below with reference to the accompanying drawings. The electrolytic cell used in the present invention is the same as the electrolytic cell of this embodiment. It is not limited.

FIG. 1 is a longitudinal sectional view of a fixed-bed type three-dimensional electrode electrolytic cell according to the present invention, and FIG. 2 is an example of a configuration of a water treatment apparatus using the fixed-bed type three-dimensional electrode electrolytic cell of the present invention. Show. FIG. 3 shows another example of the configuration of the water treatment apparatus using the fixed-bed type three-dimensional electrode electrolytic cell of the present invention.

FIG. 4 shows a water treatment apparatus using a comparative fixed-bed type three-dimensional electrode electrolytic cell.

In each figure, for example, a carbonaceous fixed bed type three-dimensional electrode 21 of a carbon graphite electrode is laminated, and the carbonaceous fixed bed type three-dimensional electrode 21 is composed of a metal electrode (for example, platinum-plated titanium mesh) 22 and Sandwiched at 22 '. The carbonaceous fixed-bed type three-dimensional electrode 21 and the metal electrodes 22 and 22 ′ are held by an elastic gasket (for example, made of EPDM rubber) 23, and are fixed on the inner surface of the cylindrical body 26 of the fixed-bed type three-dimensional electrode electrolytic cell 20. In close contact. The water to be treated is 0.5 to 5 k from the IN side of the electrolytic cell 20.
g / cm ² , and a DC power supply 1 provided outside the electrolytic cell 20 to the terminal electrodes 24 and 24 ′.
By applying a voltage from 0, the water to be treated is sterilized and taken out from the OUT side.

As shown in FIGS. 2 and 3, the water treatment apparatuses 100 and 110 of the present invention
1. There is provided a hydrogen peroxide addition section 40 comprising a liquid sending pump 42 and a valve 43. Further, a water storage tank 51 is provided, and the water to be treated in the water storage tank 51 is sent out by a pump 52, passes through a filtration device 53 while being added with hydrogen peroxide water in a hydrogen peroxide addition section 40, and is fixed-bed type three-dimensional. The water to be treated, which has entered the electrode electrolytic cell 20 and has been treated in the electrolytic cell 20, is returned to the water storage tank 51 again to form a circulation path for the water to be treated.
After activation, the water to be treated in the water storage tank 51 is sterilized in a short time, and the state can be maintained for a long time.

FIG. 3 shows that the water to be treated enters the water storage tank 51 from the use point via the activated carbon tank 61 and the ion exchange device 62 in addition to the configuration of FIG. The treated water is distributed from the water storage tank 51 to the use point again.

FIG. 4 shows a configuration of a comparative example, in which the hydrogen peroxide addition section 40 is omitted from FIGS.

As described above, the hydrogen peroxide addition section 40 is provided in the water to be treated on the upstream side of the electrolytic cell 20 and the organic substance is added to the water to be treated by continuously or intermittently adding the hydrogen peroxide. Even if it is included, it has become possible to maintain a high bacteriostatic effect for a long period of time.

The water to be treated has an electric conductivity of 0.1 μS /
cm of pure water to 30 μS / cm or less of pure water or recycled water thereof.

[0047]

Next, the present invention will be described based on examples, but embodiments of the present invention are not limited to these examples.

Example 1 Using the electrolytic cell 20 shown in FIG. 1, a water treatment apparatus 100 of the present invention shown in FIG. 2 and a comparative water treatment apparatus 120 shown in FIG. 4 were produced. The fixed bed 21 was made of porous carbon graphite (average pore diameter 50 μm), 9 mm in thickness, and 76 mm in diameter. Each fixed floor 21
Are sandwiched between platinum-coated titanium mesh electrodes having a thickness of 1 mm, the fixed beds 21 are arranged at an interval of 1 mm on the inner surface of the cylindrical body 26 of the electrolytic cell 20, and the power supply electrodes 30, 30 made of platinum-coated titanium mesh at both ends. '. Terminal electrodes 24, 2 are connected to the power supply electrodes 30, 30 '.
A DC 34 V from the DC power supply 10 was applied through 4 ', and the polarity was inverted at intervals of 15 minutes. 5 in the water tank 51
A 0 liter tank was used.

The bacteriostatic performance test was carried out by Diminuta was cultured for 3 days using a liquid medium (normal broth medium, manufactured by Eiken Chemical Co., Ltd.), and the cells were centrifuged at 5000 rpm.
It was washed with pure water and centrifuged again. This was added to previously stored pure water (electrical conductivity 1 μS / cm) to obtain treated water. This water is sent to the electrolytic tank 20 of the water treatment apparatus 100 of the present invention and the electrolytic tank 20 of the water treatment apparatus 120 of the comparative example at a pressure of 1.2 kg / cm ² , and the water to be treated before and after passing through the electrolytic tank 20 is collected. After watering, the number of viable bacteria contained therein was measured by an agar plate method using an ordinary agar medium (manufactured by Eiken Chemical Co., Ltd.).

In the example of the present invention, the hydrogen peroxide concentration is 100
ppm was continuously added.

The cells were added periodically (added amount: 5 × 10 ⁶ CFU / week) during continuous operation in the circulation treatment, and the treatment was continued.

Table 1 shows the results.

[0053]

[Table 1]

From Table 1, it was found that the water treatment apparatus 100 of the present invention was clearly superior in bacteriostatic efficiency and stable over a long period of operation than the water treatment apparatus 120 of the comparative example.

Example 2 In the same manner as in Example 1, the concentration of hydrogen peroxide added was 1 to 1
The addition was performed at 0000 ppm, and the addition time was changed continuously or intermittently. It was continuously circulated for 3 months. At the start of the operation and after three months, the P.T. diminut
passing through the water to be treated (about 10 ⁵ CFU / ml) containing
The number of bacteria before and after passing through the electrolytic cell 20 was measured to determine the bacteriostatic rate.
In addition, as a comparative example, a case where hydrogen peroxide was not added only by energizing the electrolytic cell 20 and a case where hydrogen peroxide was added without energizing were tried. Table 2 shows the results.

Incidentally, the bacteriostatic rate (%) = (1−the number of viable bacteria in the water to be treated after passing through the electrolytic cell / the number of viable bacteria in the water to be treated before passing through the electrolytic cell) × 100.

[0057]

[Table 2]

It has been confirmed that the water treatment method of the present invention can maintain high bacteriostatic performance for a long period of time.

[0059]

According to the present invention, in a method for electrochemically treating microorganisms or the like in water to be treated using a fixed-bed type three-dimensional electrode electrolytic cell, even if the water to be treated contains an organic substance, the method is effective for a long time. Thus, it was possible to provide a treatment method which maintains high bacteriostatic performance over a long period of time and has less clogging with organic substances.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of a fixed-bed type three-dimensional electrode electrolytic cell according to the present invention.

FIG. 2 is a configuration diagram of a water treatment apparatus including a fixed-bed type three-dimensional electrode electrolytic cell according to the present invention.

FIG. 3 is a configuration diagram of another example of a water treatment apparatus including a fixed-bed type three-dimensional electrode electrolytic cell according to the present invention.

FIG. 4 is a configuration diagram of a conventional water treatment apparatus including a fixed carbonaceous fixed bed type three-dimensional electrode electrolytic cell.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 DC power supply 20 Fixed-bed type three-dimensional electrode electrolytic cell (carbonaceous fixed-bed three-dimensional electrode electrolytic cell, carbonaceous fixed-bed three-dimensional bipolar electrode tank) 21 Fixed-bed type three-dimensional electrode (fixed-bed) 22 , 22 'Metal electrode 23 Gasket 24, 24' Terminal electrode 26 Tubular body 30, 30 'Power supply electrode 40 Hydrogen peroxide addition unit 41 Hydrogen peroxide water tank 42 Liquid feed pump 43 Valve 51 Water tank 52 Pump 53 Filtration device 61 activated carbon tank 62 ion exchange device 100 water treatment device 110 water treatment device 120 conventional water treatment device

Claims (6)

[Claims] In a water treatment method using a fixed-bed type three-dimensional electrode electrolytic cell for electrochemically treating water to be treated by passing the water through a fixed-bed type three-dimensional electrode electrolytic cell, the water to be treated is subjected to peroxide treatment. A water treatment method comprising adding hydrogen continuously or intermittently and treating the water to be treated by passing the water through a fixed-bed type three-dimensional electrode electrolytic cell. 2. The water treatment method according to claim 1, wherein the addition concentration of the hydrogen peroxide in the addition section is 1 to 10000 ppm with respect to the water to be treated. 3. The water treatment method according to claim 1, wherein during the water treatment period, the average addition amount of the hydrogen peroxide in the addition section is 24 to 10000 ppm · hr / day. 4. The water to be treated has an electric conductivity of 30 μS / c.
The water treatment method according to any one of claims 1 to 3, wherein the water is pure water or recycled water of pure water of m or less. 5. A water treatment apparatus using a fixed-bed type three-dimensional electrode electrolytic cell for electrochemically treating water to be treated by passing the water through a fixed-bed type three-dimensional electrode electrolytic cell. A water treatment device comprising a device for continuously or intermittently adding hydrogen. 6. The means for continuously or intermittently adding hydrogen peroxide includes at least a hydrogen peroxide water tank,
The water treatment apparatus according to claim 5, further comprising a liquid supply pump configured to supply a constant amount of the hydrogen peroxide solution from the tank into a supply pipe of the water to be treated to the electrolytic cell.