JPH11277065A - Method and apparatus for sterilizing water - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the efficiency of an electrode reaction, to save energy, and to reduce cost by using the aggregate of titanium fibers as an anode when raw water is passed through an electrolytic bath having the anode and a cathode to eliminate microorganisms contained in the raw water. SOLUTION: In an electrolytic tic bath 1, a cylindrical cathode 3 and a cylindrical anode 4 are installed in the lower half part and upper half part of a cylindrical bath main body (of polypropylene), respectively. Here, as an anode 4, an object comprising the aggregate of titanium fibers is used. The titanium fibers are preferably are manufactured by a cutting method. Namely, a thin titanium plate is wound up into a coil, which is being rotated, the end face wounded is cut in the circumferential direction by a cutting blade, and a continuous bundle of the titanium fibers is produced. The structure of the aggregate of titanium fibers to be the anode 4, as required, can be optional structure of the shape of cloth, felt, nonwoven fabric, mat, or the like.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for sterilizing water and an apparatus used for the method. For more information,
The present invention relates to a method for sterilizing microorganisms in service water by passing the service water through an electrolytic cell provided with a specific electrode, and an apparatus used for the method.

[0002]

2. Description of the Related Art Conventionally, drinking water used in homes and offices,
As a method of disinfecting various types of water, such as hot water in public baths, pool water, or cooling water for heat exchangers in factories or buildings, generally, a method of boiling the water, a method of dissolving chlorine or excess water in the water. A method of adding a bactericide such as hydrogen oxide or a method of electrolytic sterilization is known. However, the boiling method has a problem that the energy consumption required for the boiling is large, the management of the heat source is complicated, and the characteristics of the water change due to the boiling, so that it cannot be applied depending on the purpose of the water. . In addition, the method of adding chlorine is widely applied as a sterilization treatment method of tap water, but it is necessary to add a large amount of chlorine, a chlorine odor remains, and an organic chlorine compound (for example, trichloride) There is a problem that methane) may be generated to impair human health or cause environmental pollution. In addition, the method of adding hydrogen peroxide requires that a relatively large amount of hydrogen peroxide be added because hydrogen peroxide is easily decomposed in an aqueous system. There is a problem that handling during transportation and loading may be dangerous. Furthermore, the method of electrolytic sterilization requires a relatively large amount of electric power, which increases the cost, that the sterilization becomes insufficient when the voltage is reduced in order to reduce the amount of electric power, and that sufficient sterilization is performed. However, when the voltage is increased, there is a problem that water itself is decomposed and harmful gas is generated.

[0003] In recent years, water has been introduced into an electrolytic cell having a carbon fiber mat cathode having polyaniline adhered to the surface thereof and a porous plate-shaped anode, and electricity is continuously supplied between the cathode and the anode. A method has been proposed in which the dissolved oxygen contained in the service water is reduced by the action of polyaniline to generate superoxide, thereby disinfecting the microorganisms contained in the service water. Proceedings of the "Functional Water Symposium '96" hosted by the Water Research Promotion Foundation
95 (November 28, 1996). This method is based on the invention previously filed by the present inventors (Japanese Patent Application No. Hei 8-
No. 208243).
Although this is an excellent method that has solved the above-mentioned problems in the conventional general water sterilization method, it has a problem that the efficiency of the electrode reaction is not yet sufficiently satisfactory.

[0004]

SUMMARY OF THE INVENTION The object of the present invention is, of course, to solve the above-mentioned various problems in the conventional general method of sterilizing water for use. An object of the present invention is to solve the problem that the efficiency of the electrode reaction of the sterilization treatment method for water is low.

[0005]

In order to achieve the above object, a method for sterilizing water according to the present invention is characterized in that water to be treated is treated with an anode and a cathode comprising a conductive porous body having polyaniline adhered to the surface. And passed through the intermittent or continuous electric current between the cathode and the anode to reduce dissolved oxygen contained in the water to be treated, thereby obtaining superoxide. In the method of disinfecting microorganisms contained in the water to be treated by generating
An aggregate of titanium fibers is used as the anode. Further, the sterilization treatment apparatus according to the present invention is an apparatus used in the sterilization treatment method for water according to the above-described present invention, and includes an inlet and an outlet for water to be treated in the tank main body. An electrolytic cell in which a cathode made of a conductive porous body having polyaniline adhered to the surface thereof and an anode made of an aggregate of titanium fibers are disposed in the tank main body so as to be in contact with the water to be treated flowing to the outlet. And a power supply for applying a current to the anode and the cathode, and a facility for supplying the water to be treated to the electrolytic cell. The method and apparatus for sterilizing water according to the present invention as described above, as a result of the inventors' intensive studies to achieve the above object, the use of an aggregate of titanium fibers as the anode improves the efficiency of the electrode reaction. The present invention has been achieved by finding that the sterilization treatment of water can realize further energy saving and cost reduction. Further, if the aggregate of titanium fibers is used as the anode, there is an advantage that the structure of the anode can be arbitrarily selected to various structures as required.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The water to be treated to which the present invention is applied is not particularly limited, and may be of any water quality such as tap water, groundwater, industrial water, drinking water, hot water in public baths, and the like. It may be used for any purpose such as pool water or cooling water for heat exchangers in factories or buildings. Examples of microorganisms that can be sterilized by the present invention include bacteria (bacteria), fungi, filamentous fungi (fungi), Escherichia coli, yeast, deformed fungi, unicellular algae, protozoa, and viruses.

As the cathode provided in the electrolytic cell used in the present invention, a cathode made of a conductive porous material having polyaniline adhered to the surface is used. Here, the polyaniline is a polymer containing at least one of the polyanilines represented by the following formulas (1), (2), (3) and (4).

[0008]

Embedded image

In the above formulas (1) to (4), n is 2
Is an integer in the range of 5000, preferably 10-1000, and x and y are numbers that simultaneously satisfy x + y = 1 and 0 ≦ y ≦ 0.5. Further, the above equations (1) and (3)
In the formula, A ^- is a negative ion, and examples thereof include sulfuric acid, perchloric acid, trifluoroacetic acid, boron trifluoride, polyacrylic acid, polystyrenesulfonic acid, cresolsulfonic acid, camphorsulfonic acid, and long-chain alkylbenzene sulfone. And negative ions such as acids.

The polyaniline can be produced by a conventionally known method in which an aniline monomer is polymerized by a chemical polymerization method using an oxidizing agent or an electrolytic polymerization method. When produced by a chemical polymerization method using an oxidizing agent, a doped polyaniline represented by the above formula (1) or (3) is obtained, which is neutralized with an alkali to obtain the above formula (2) Alternatively, a undoped polyaniline represented by (4) is obtained.

In the method of sterilizing water for use of the present invention, polyaniline functions as shown in FIG. That is, when dissolved oxygen (O ₂ ) contained in the water to be treated comes into contact with polyaniline, it is reduced to superoxide (· O ₂ ⁻ ). The superoxide referred to here is also called a superoxide anion or a superoxide anion radical. Then, a dimer (a) of an aniline having a reduced structure in the repeating unit in the polyaniline that has contributed to the reduction of the dissolved oxygen (O ₂ )
Is once converted into an aniline dimer (b) having an oxidized structure, which is reduced by a reduction current flowing through an electrode (cathode) and returned to the reduced structure (a) again. That is, by flowing a reduction current through the electrode (cathode), the polyaniline is maintained in a state capable of reducing dissolved oxygen (O ₂ ) (a state including a dimer of aniline having a reduced structure). Superoxide can be substantially semipermanently generated to perform sterilization treatment of water. FIG. 1 shows an example of undoped polyaniline among polyanilines. In the formula shown in FIG. 1, n, x and y are the same as those in the above formulas (2) and (4).

The material of the cathode body provided in the electrolytic cell used in the present invention is conductive, polyaniline easily adheres to the surface thereof, is not corrosive, is damaged by electricity,
Any material that is chemically and electrically stable without decomposing or causing an unnecessary chemical reaction may be used. As the structure, a porous body is employed in order to increase the surface area of polyaniline to be attached and to facilitate passage of water to be treated. Examples of the conductive porous body of the cathode body include a carbon fiber cloth (woven cloth), a carbon fiber nonwoven fabric, a carbon fiber felt, a carbon fiber paper, a carbon fiber mat, a scroll of carbon fiber yarn, and a carbon fiber having a large number of continuous holes. Raw material three-dimensional molded articles and the like can be mentioned. Carbon fibers are conductive, non-toxic, do not produce ions or hydroxides, do not have the corrosive properties of ordinary metals, are fibrous, have a large surface area, are relatively inexpensive, and form electrodes. It is one of the most preferable materials for the electrode material because the processing is easy when it is performed.

As a method for adhering polyaniline to the surface of the conductive porous body of the cathode body as described above, a polyaniline powder is obtained by polymerizing an aniline monomer by the above-mentioned chemical polymerization method, and then the powder is coated with an adhesive. And a method in which an aniline monomer is directly polymerized on the surface of the conductive porous body by the above-mentioned electrolytic polymerization method to form a polyaniline film on the surface of the conductive porous body.
The amount of polyaniline to be attached to the cathode body is not particularly limited, but is generally in the range of 0.1 to 30% by weight based on the weight of the conductive porous body of the cathode body. Further, it is desirable that the polyaniline film be thinly and uniformly adhered to the entire surface of the conductive porous body of the cathode body as much as possible so as not to lose its porosity. However, if it is too thin, the strength of the film becomes small, and there is a risk of falling off. On the other hand, if the thickness is too large, the production cost increases, the flow of current deteriorates, it becomes difficult to regenerate polyaniline from the oxidized form to the reduced form, and the pores (pores) of the porous body are narrowed, so that the water to be treated is Distribution is hindered. Generally, the preferred film thickness is 0.1 to 10 μm
m.

As the anode provided in the electrolytic cell used in the present invention, an anode composed of an aggregate of titanium fibers is used. Titanium fibers are electrically conductive, have excellent corrosion resistance, are less likely to be damaged, decomposed, or cause unnecessary chemical reactions upon energization, and are relatively stable chemically and electrically. Further, the material is relatively inexpensive and easy to process. And this is a big reason to use the aggregate of titanium fibers as the anode, but titanium fibers, like carbon fibers, have a large surface area, easily adjust the area balance between the cathode and the anode, and have the best electrode reaction efficiency. The area balance between the cathode and the anode can be easily obtained. Therefore,
According to the present invention, the efficiency of the electrode reaction can be easily improved. The use of carbon fibers for the anode is not preferred because decomposition may occur when the voltage is too high (there is no problem when used for the cathode).

The use of a perforated titanium plate for the anode has a smaller surface area than titanium fibers and makes it difficult for current to flow. As a result, the effect (sterilizing effect) of the electrodes is reduced, and compared to titanium fibers. There is a problem that workability deteriorates, the electrode structure is limited, and as a result, an efficient device cannot be designed and the cost increases.

As the titanium fibers constituting the anode, those produced by the cutting method described in JP-A-4-93123 are preferably used. That is, the cutting method, specifically, winding a thin titanium plate in a coil shape, while rotating it, cutting the wound end face in the circumferential direction with a cutting blade,
This is to produce continuous bundles of titanium fibers. The structure of the aggregate of titanium fibers to be used as the anode may be an arbitrary structure such as a cloth (woven cloth), a felt, a nonwoven fabric, or a mat, if necessary.

The cell body of the electrolytic cell used in the present invention includes:
An electrically insulating material that can withstand long-term use and is preferably used, is generally made of a synthetic resin. The outer shape is
It can be appropriately selected depending on the positions of the inlet and outlet of the water to be treated and the arrangement of the electrodes in the tank main body. Specific examples include a box shape and a cylindrical shape. The above-mentioned cathode and anode are usually disposed at a predetermined interval in the tank body, but if necessary, a separator may be provided between the two electrodes to insulate the two electrodes. As this separator, for example, a glass fiber cloth, an electrically insulating organic polymer porous film, a ceramic porous film, or the like is used. Among the organic polymer porous membranes, ultra-high molecular polyethylene porous membranes have high strength, are hard to break, are chemically and electrically stable, and adjust the pore size and porosity. It is most preferably used because it can be easily formed and the size and thickness of the film can be freely selected. Further, in the tank body of the electrolytic cell used in the present invention, if necessary, a filter may be provided after the inlet of the water to be treated in order to remove dust and foreign matters in the water to be treated in advance. A filter may be provided in front of the outlet to remove dead microorganisms and the like from the sterilized water. Further, such removal of dust or foreign matter in the water to be treated or removal of dead bodies of microorganisms from the sterilized water may be performed with a filter provided separately from the electrolytic cell, if necessary. Good.

In carrying out the sterilization treatment method of the present invention, the current applied to the electrode may be as small as necessary for the stable regeneration of the polyaniline attached to the cathode surface from the oxidized form to the reduced form. . If the current is increased unnecessarily, harmful gas is generated due to the electrolytic reaction of water itself, which is not preferable. Generally, 0.01 to 100 μA
-About cm ^-2 is appropriate. The time for which the water to be treated stays in the electrolytic cell may be appropriately set according to the quality of the water to be treated, the use after the treatment, the scale of the treatment, and the like, but generally 5 to 60 seconds is appropriate. If the residence time is too short, the sterilization of the microorganisms becomes insufficient, and if the residence time is too long, the efficiency is lowered practically and it is not economical. In addition, if necessary, the water to be treated may be repeatedly passed through the electrolytic cell to carry out the circulation treatment.

According to the sterilization treatment method of the present invention, the water to be treated can be sterilized and the surface tension of the water to be treated can be reduced. Water with reduced surface tension is useful as so-called functional water, for example, having the effect of promoting germination or growth of plants.

In carrying out the sterilization treatment method of the present invention, an inlet and an outlet for water to be treated are provided, and polyaniline is adhered to the surface so as to come into contact with the water to be treated flowing from the inlet to the outlet. An electrolytic cell having various structures can be used, if necessary, as long as the electrolytic cell is provided with a cathode made of a conductive porous material and an anode made of an aggregate of titanium fibers. In order to carry out the sterilization treatment method of the present invention, a power source for supplying an electric current to the electrode of the electrolytic cell and a facility for supplying water for treatment including a pump, a hose, a water tank and the like are required. Hereinafter, a preferred example of the structure of the sterilization apparatus used for performing the sterilization method of the present invention will be described.

In a first embodiment of the sterilizing apparatus according to the present invention, the inlet and outlet of the water to be treated are provided at positions separated from each other in the electrolytic cell main body, and the water to be treated flowing from the inlet to the outlet is provided. A cathode made of a conductive porous body having polyaniline adhered to the surface thereof on the inlet side in the tank body so as to sequentially contact and collect, and a collection of titanium fibers on the discharge port side in the tank body. And an anode made of a body. The inlet and the outlet may be arranged at positions separated from each other, and among them, when they are arranged at positions facing each other, it is preferable because the water to be treated easily passes through the inside of the tank body. As a specific example, there is a case in which it is provided on the left and right of the box-shaped tank main body, a case in which it is provided in the vertical direction, and a case in which it is provided on two bottom surfaces of the cylindrical tank main body.

FIG. 2 is a schematic cross-sectional view of an example of the electrolytic cell according to the first embodiment. The electrolytic cell 1 shown in FIG. 2 has a columnar cathode 3 made of a carbon fiber mat having a polyaniline film adhered to the lower half of a cylindrical cell body (made of polypropylene) 2 and a titanium fiber felt in the upper half. Are provided at the bottom of the cylindrical tank body 2, an inlet 5 for the water to be treated is provided at the top thereof, and an outlet 6 for the water to be treated is provided at the top thereof. Inlet 5
Through the cylindrical cathode 3, then through the cylindrical anode 4, and discharged from the top of the cylindrical tank 2 through the outlet 6. Have been. Each of the columnar cathode 3 and the columnar anode 4 is provided with an electrode terminal (platinum wire) 7, and a current is supplied to each of the electrode terminals 7 from a power supply (not shown). In the electrolytic cell 1 of FIG. 2, in addition to the cathode 3 and the anode 4, between the cathode 3 and the anode 4, the lower surface of the cathode 3 (the surface on the inlet 5 side) and the upper surface of the anode 4 ( A disc-shaped separator (made of glass fiber cloth) 8 is provided on the surface on the side of the discharge port 6), and further on the separator 8 on the lower surface of the cathode 3 and on the separator 8 on the upper surface of the anode 4, respectively. A disc-shaped filter (made of polypropylene fiber felt) 10 is provided via a disc-shaped perforated plate (made of polypropylene) 9. The to-be-treated water 11 is supplied from the to-be-treated water tank 12 to the electrolytic cell 1 through the inlet 5 by the pump 14 through the hose 13, is discharged from the outlet 6 through the electrolytic cell 1, and is supplied through the hose 15. It is returned to the tank 12. In addition, not only the case where one cathode and one anode are arranged as shown in FIG. 2, but a plurality of electrode pairs are provided in the direction from the inlet to the outlet of the water to be treated,
The water for treatment may be repeatedly brought into contact with the polyaniline.

In a second embodiment of the sterilization apparatus according to the present invention, an electrolytic cell main body is provided with an inlet for water to be treated, and a cylindrical core material made of a porous material is provided in the tank main body. Is provided so as to communicate with the inlet, and on the outer periphery of the cylindrical core material, a cylindrical cathode made of a conductive porous body having polyaniline adhered to the surface thereof, a cylindrical separator, and an aggregate of titanium fibers. A tubular anode is provided to form a tubular electrode pair, and the tank main body is provided with an outlet for the water to be treated flowing out from the tubular electrode pair. That is, the water to be treated introduced into the core hollow portion from the inlet port flows out of the cylindrical core material through the hole, and then passes through the pair of cylindrical electrodes surrounding the outer periphery of the cylindrical core material. It is preferable to be configured so as to be in contact with the electrode pair and finally discharged to the outside of the electrolytic cell.

Here, as the material of the cylindrical core material, any material can be used as long as it is insulative and can withstand long-term use. Specifically, polypropylene, polyethylene, ultrahigh molecular weight polyethylene, polyvinyl chloride, Examples include polystyrene, polyamide, and polyester. The porosity can be appropriately set so as not to hinder the flow of the water to be treated, and specifically, is preferably about 30 to 70% (ratio of void volume / apparent volume of core material). Also,
Providing a gap between the outer peripheral surface of the cylindrical electrode pair and the inner peripheral surface of the electrolytic cell, between the inlet and the hollow core, or between the outer peripheral surface of the cylindrical electrode pair and the outlet. Can be.
Thereby, the introduction and discharge of the water to be treated is performed through the gap, so that the flow becomes smoother and a constant treatment efficiency can be secured for the entire electrolytic cell. Further, the position of the outlet is not particularly limited as long as the water to be treated flowing out of the cylindrical electrode pair can be discharged, and the outlet is provided in the tank body along the outer peripheral surface of the cylindrical electrode pair, or at another position. This is also applicable because the water to be treated can be guided to the position by appropriately providing the above-mentioned gap.

FIG. 3 is a schematic sectional view of an example of the electrolytic cell according to the second embodiment. The electrolytic cell 21 shown in FIG. 3 has a core (made of polypropylene) 29 made of a cylindrical porous body in the center of a cylindrical cell body (made of polypropylene) 22 and a carbon fiber yarn wound around the outer periphery thereof in a cylindrical shape. A cylindrical cathode 23 made of a polyaniline film adhered to a cylindrical separator, a cylindrical separator (made of glass fiber cloth) 28 on its outer periphery, and a cylindrical anode 24 formed by winding a titanium fiber sliver in a cylindrical shape on its outer periphery. And the cylindrical tank body 22
An inlet 25 for the water to be treated is provided at the bottom of the container, and an outlet 26 for the water to be treated is provided at the upper side surface thereof. The water to be treated is supplied from the inlet 25 to the hollow core of the core material 29 made of a cylindrical porous body. It is introduced into the lower part, passes through the cylindrical cathode 23, the cylindrical separator 28, and the cylindrical anode 24 in order while ascending the core hollow part, and is discharged through the outlet 26 on the upper side surface of the cylindrical tank body 22.
It is configured to be discharged from. Cylindrical cathode 23
Each of the cylindrical anodes 24 is provided with an electrode terminal (platinum wire) 27, and a current is supplied to each of the electrode terminals 27 from a power supply (not shown). Water for treatment 11
2 is supplied from the water tank 12 to be treated to the electrolytic cell 21 through the inlet 25 by the pump 14 through the hose 13 as in the case of FIG.
From the tank and the water tank 1
Returned to 2. The water to be treated is not limited to the case where the cylindrical cathode, the cylindrical anode, and the cylindrical separator are arranged one by one as shown in FIG. You may make it contact.

In a third embodiment of the sterilization apparatus according to the present invention, an electrolytic cell main body is provided with an inlet and an outlet for water to be treated, and a thin plate-like anode made of an aggregate of titanium fibers is provided in the cell main body. On both sides, via a thin plate separator, a plate electrode unit integrating a thin plate cathode made of a conductive porous body with polyaniline adhered to the surface, the water to be treated meanders between the plate electrode units. They are separated from each other so as to flow. In addition, the method of integrating the above-mentioned thin plate-shaped anode, cathode, and separator is a method of bonding both sides of each material with an adhesive so that the flow of water is not obstructed as much as possible, and a method of forming each material in a predetermined form. After that, a method of injecting an adhesive only on both sides and fixing the adhesive may be appropriately selected. The number of the plate-shaped electrode units provided in the tank body may be one or more, but it is preferable to use a plurality of the plate-shaped electrode units in order to more efficiently contact the water to be treated and the cathode. Further, it is preferable that a plurality of plate-shaped electrode units are arranged in parallel and alternately in the tank body. With the above configuration, the water to be treated can be brought into contact with polyaniline over a long distance from the inlet to the outlet without increasing the size of the electrolytic cell, so that the sterilization treatment is efficiently performed, which is preferable. .

FIG. 4 is a schematic sectional view of an example of the electrolytic cell according to the third embodiment. The electrolytic cell 31 shown in FIG. 4 is provided in a box-shaped cell main body (made of polypropylene) 32 on both sides of a thin plate anode 34 made of titanium fiber felt via a thin plate separator (made of porous ultrahigh molecular weight polyethylene) 38. A plurality of (X _{1 to} X _n ) plate-shaped electrode units X each having a thin plate-shaped cathode 33 made of a carbon fiber cloth having a polyaniline film adhered to the surface thereof are arranged in parallel at a predetermined interval, and have a box-like shape. An inlet 35 for the water to be treated is provided on one surface of the upper part of the tank body 32, and an outlet 36 for the water for treatment is provided on the other surface of the upper part of the tank main body 32.
5 is introduced into the top of one side of the box-like tank body 32 from, first, down through between the inner and one surface of the plate-shaped electrode unit X ₁ of the box-like tank body 32, and then the plate-shaped electrode unit X ₁ rises between the other face and one face of the plate-shaped electrode unit X _2,
Then, as that descends between the one surface of the other surface and the plate-shaped electrode unit X ₃ of the plate-shaped electrode unit X _2, flow meanders between the plurality of plate-shaped electrode unit X into a plurality of times up and down, Finally, the discharge port 3 on the other upper surface of the box-shaped tank body 32
6 to be discharged. An electrode terminal (platinum wire) 37 is provided on each of the cathode 33 and the anode 34 of each plate-shaped electrode unit X, and a current is supplied to each of the electrode terminals 37 from a power supply (not shown). The water for treatment 11 is supplied from the water for treatment tank 12 through the hose 13 to the electrolytic cell 31 via the inlet 35 by the pump 14 through the hose 13, and is discharged from the outlet 36 through the electrolytic cell 31 as in the case of FIG. 2. Then, the water is returned to the water tank 12 through the hose 15.

In a fourth embodiment of the sterilization apparatus according to the present invention, an electrolytic cell main body is provided with an inlet for water to be treated, and a cylindrical core material made of a porous material is provided in the tank main body. Is provided so as to communicate with the introduction port, and on the outer periphery of the cylindrical core material, an annular anode made of an aggregate of titanium fibers, an annular separator, and an annular formed of a conductive porous body having a polyaniline film adhered to the surface. A cathode and a cylindrical electrode assembly formed by laminating the tubular core along the longitudinal direction thereof, and the tank main body provided with an outlet for the water to be treated flowing out of the cylindrical electrode assembly. It is. That is, the water to be treated introduced into the hollow core portion from the inlet port flows out of the cylindrical core member through the hole, and then passes through the cylindrical electrode assembly surrounding the outer periphery of the cylindrical core member. It is preferable that the electrode assembly is configured to be brought into contact with the electrode assembly and finally discharged to the outside of the electrolytic cell. Note that the material and porosity of the cylindrical core material, the provision of voids in the electrolytic cell, the position of the outlet, and the like are the same as in the case of the above-described second embodiment.

FIG. 5 is a schematic sectional view of an example of the electrolytic cell according to the fourth embodiment. The electrolytic cell 41 of FIG. 5 has a core (made of polypropylene) 49 made of a cylindrical porous body as a core in a cylindrical cell body (made of polypropylene) 42.
A cylindrical electrode assembly is formed by alternately stacking a plurality of annular anodes 44 made of titanium fiber felt, an annular separator (made of porous ultra-high molecular weight polyethylene) 48, and an annular cathode 43 made of a carbon fiber cloth having a polyaniline film adhered to the surface. Y is formed, and a cylindrical gap is provided between the outer periphery of the electrode assembly Y and the inner periphery of the cylindrical tank body 42,
An inlet port 45 for water to be treated is provided at the bottom of the cylindrical tank main body 42, and an outlet port 46 for water to be treated is provided on an upper side surface thereof. Is introduced into the lower portion of the hollow core portion, passes through the cylindrical electrode assembly Y while ascending the hollow core portion, and has a cylindrical shape between the outer circumference of the electrode assembly Y and the inner circumference of the cylindrical tank body 42. It is configured to flow into the gap, rise up the gap, and be discharged from the discharge port 46 on the upper side surface of the cylindrical tank body 42. Each of the annular cathode 43 and the annular anode 44 is provided with an electrode terminal (platinum wire) 47, and a current is supplied to each of the electrode terminals 47 from a power supply (not shown).
The treated water 11 is supplied from the treated water tank 12 through the hose 13 to the electrolytic cell 41 via the inlet 45 by the pump 14 through the hose 13, and is discharged from the discharge port 46 through the electrolytic cell 41 in the same manner as in the case of FIG. Then, the water is returned to the water tank 12 through the hose 15.

In a fifth embodiment of the sterilization apparatus according to the present invention, an electrolytic cell main body is provided with an inlet for water to be treated, and a cylindrical core material made of a porous material is provided in the tank main body. Is provided so as to communicate with the introduction port, on the outer periphery of the cylindrical core material, an anode made of an aggregate of titanium fibers, a separator, and a cathode made of a conductive porous body having a polyaniline film adhered to the surface. The spirally wound electrode unit is formed by winding the layered product, and the tank main body is provided with an outlet for the water to be treated flowing out of the spirally wound electrode unit. That is, the water to be treated introduced from the inlet into the hollow core portion flows out of the cylindrical core material through the hole, and then passes through the spiral electrode unit surrounding the outer periphery of the cylindrical core material. It is preferable that the electrode unit is configured to be brought into contact with the electrode unit and finally discharged to the outside of the electrolytic cell. In addition, the material and porosity of the cylindrical core material, providing voids in the electrolytic cell,
The position of the outlet and the like are the same as in the case of the above-described second embodiment.

FIG. 6 is a schematic sectional view of an example of the electrolytic cell according to the fifth embodiment. The electrolytic cell 51 in FIG. 6 includes a spiral electrode unit Z in a box-shaped cell main body (made of polypropylene) 52. Here, the spiral electrode unit Z
As shown in a plan sectional view of FIG. 7 and a partially enlarged view of FIG. 8, an anode 5 made of a titanium fiber non-woven fabric with a core material (made of polypropylene) 59 made of a cylindrical porous body as a core.
4. A separator 58 made of a synthetic fiber non-woven fabric and a cathode 53 made of a carbon fiber cloth having a polyaniline film adhered to the surface thereof are alternately stacked and wound in a spiral shape. A void is formed in the lower part of the box-shaped tank main body 52 so as to communicate with the hollow core of the core material 59, and the space between the outer periphery of the electrode unit Z and the inner surface of the box-shaped tank main body 52 is formed. A void is also formed over the upper part of.
The lower surface of the box-shaped tank main body 52 is provided with an inlet 55 for the water 11 to be treated and the other upper surface thereof is provided with an outlet 56 for the water 11 to be treated. From 55, it is introduced into the hollow core of the core material 59 made of a cylindrical porous body through the lower space in the box-shaped tank main body 52, passes through the spiral electrode unit Z while ascending the hollow core,
It flows into the gap between the outer periphery of the electrode unit Z and the inner surface of the box-shaped tank body 52, rises up the gap, passes through the upper gap in the box-shaped tank body 52, and finally the It is configured to be discharged from the discharge port 56 on the other upper surface. The cathode 53 and the anode 54 are provided with electrode terminals (platinum wires) 57, respectively.
7, a current is supplied from a power supply (not shown). The to-be-treated water 11 is, like the case of FIG.
Is supplied to the electrolytic cell 51 through the inlet 55 by the pump 14 through the hose 13, is discharged from the outlet 56 through the electrolytic cell 51, and is returned to the treatment water tank 12 through the hose 15.

In manufacturing the above spiral electrode unit Z, as shown in the conceptual diagram of FIG. 9, for example, a cathode 53, a separator 58, a titanium 58 made of a conductive porous body having a polyaniline film adhered to the surface thereof, An anode 54 composed of an aggregate of fibers and a separator 58 which are stacked in this order can be easily obtained by integrally winding a plurality of turns around a core material 59 composed of a cylindrical porous body. In addition, since the spiral shape allows the combination of the anode and the cathode to be formed in multiple layers along the radial direction of the electrode unit, high processing capability can be obtained.

[0033]

EXAMPLES The present invention will be described more specifically with reference to the following examples, but the present invention is not limited to the following examples.

(Example 1) A test was conducted using a sterilization apparatus as shown in FIG. The electrolytic cell 1 used had an outer diameter of 10
In the lower half of the cylindrical tank main body 2 made of polypropylene having a length of 15 cm and a length of 15 cm, a polyaniline film was formed on the surface of a 35 g PAN (polyacrylonitrile) -based carbon fiber mat by an electrolytic polymerization method to a thickness of about 1% based on the weight of the carbon fiber. A columnar anode 4 made of a needle-punched felt of 90 g of titanium fiber manufactured by a cutting method is arranged on the upper half of the columnar cathode 3 to which 0.5% by weight is adhered. A disk-shaped separator 8 made of two glass fiber cloths is interposed between the anodes 4, and further below the cathode 3 and the anode 4.
Is provided with a disc filter 10 made of polypropylene fiber felt via a disc-shaped perforated plate 9 made of polypropylene. Water to be treated is introduced from the bottom, and a columnar cathode 3 and a columnar anode are provided. 4 and the like are sequentially passed and discharged from the top. As the to-be-processed water 11, 0.9% by weight of salt was added to distilled water, and 0.2% by weight of factory wastewater containing a large amount of general bacteria was added. 50 of the prepared water for treatment 11
00 cc into the water tank 12 to be treated,
At a flow rate of c / min, the water was supplied to the electrolytic cell 1 by the pump 14 through the hose 13 and the treated water discharged from the electrolytic cell 1 was returned to the water tank 12 through the hose 15 for circulating treatment. Energize the electrodes at the same time as the process starts,
The power supply was adjusted so that the current of the cathode 3 became -50 mA. The number of bacteria (the number of colonies) of the water sampled every predetermined time was measured by a Petri dish agar culture test. Culture conditions were 36 ° C. for 24 hours. Table 1 shows the results of the culture test. For comparison, the same operation as above was performed, except that the electrode was not energized, the treatment water to be treated was circulated in the same manner as above, and the culture test was performed on the water sampled at predetermined time intervals in the same manner as above. (Comparative Example 1). Further, the water to be treated prepared in the same manner as above was allowed to stand, sampled at predetermined time intervals, and a culture test was performed on the sampled water in the same manner as described above (Comparative Example 2). Table 1 shows the results of these culture tests.

[0035]

[Table 1]

As is clear from the above Table 1, in the case of the water to be treated as used in the present embodiment, only 50 mA was applied to the electrode using the carbon fiber to which the polyaniline film was attached as the cathode and the titanium fiber as the anode. By passing a small electric current, general bacteria can be killed in a few hours, and all bacteria can be killed in 24 hours.
The effect can last more than 50 hours. When no electricity was supplied (Comparative Example 1), there was a sterilizing effect for several hours,
After 24 hours, the sterilizing effect is lost. From this, it is clear that the activity of the polyaniline film is lost within a few hours when no current is applied, and the activity is regenerated when the current is applied.

(Example 2) A test was performed using a sterilization apparatus as shown in FIG. The electrolytic cell 21 used had an outer diameter of 1
A core material 29 made of a polypropylene cylindrical porous body having a diameter of 25 mm and a length of 50 cm is placed in a polypropylene cylindrical tank body 22 having a length of 0 cm and a length of 55 cm.
A cylindrical cathode 23 in which 00 g of a PAN-based carbon fiber yarn is wound in a cylindrical shape and a polyaniline film is adhered to the surface thereof by electrolytic polymerization at about 2% by weight based on the weight of the carbon fiber, and the basis weight is 300 g / m ^{2 on the} outer periphery thereof. A cylindrical separator 24 in which a glass fiber cloth is wound twice and a cylindrical anode 24 is formed by winding 300 g of a sliver in which 300 titanium fibers having a diameter of 0.05 mm bundled by a cutting method are bundled into a cylindrical shape. Are provided, and the water to be treated is
Is introduced into the lower portion of the hollow core portion, and passes through the cylindrical cathode 23, the cylindrical anode 24, and the like while rising up the hollow core portion, and is discharged from the upper side surface. As the water 11 to be treated, 100 l of distilled water, 35
g and 5 l of factory wastewater containing general bacteria were prepared. The prepared water for treatment 11 is put into a water tank for treatment 12 and the hose 13 is supplied at a flow rate of 10 l / min.
Was supplied to the electrolytic cell 21 by the pump 14, and the treated water discharged from the electrolytic cell 21 was returned to the water tank 12 to be treated through the hose 15 and circulated. The electrode is energized at the same time as the processing starts, and the current of the cathode 23 is -200 m
The power supply was adjusted to A. 49
After the lapse of time, 5 l of the above-mentioned factory wastewater was added again to the circulated water to be treated, and the circulating treatment was continued in the same manner as described above. The hydrogen peroxide concentration and the number of bacteria (the number of colonies) were measured for the water sampled at predetermined time intervals. The measurement of the hydrogen peroxide concentration was carried out by a peroxide test method manufactured by BIOTECHNIK. The number of bacteria was measured by the Petri dish agar culture test method. Culture conditions are 36 ° C, 24
It was time. Table 2 shows the results of these measurements.

[0038]

[Table 2]

As is clear from Table 2, if the water to be treated as used in the present embodiment was used, only 200 mA was applied to the electrode using the carbon fiber to which the polyaniline film was attached as the cathode and the titanium fiber as the anode. Just passing a small current of
General bacteria are killed in a few hours. Further, even if bacteria are added to the water to be treated, the activity of polyaniline is not lost, and sterilization can be performed semipermanently. In addition, since the amount of hydrogen peroxide increases with the treatment time, it is clear that superoxide is definitely generated inside the electrolytic cell, becomes a source of sterilization, and changes to hydrogen peroxide.

Example 3 A test was conducted using the same sterilization apparatus as in Example 2. Core 2 made of a cylindrical porous body made of polypropylene and having a diameter of 2.5 cm and a length of 50 cm
9, a PAN-based carbon fiber cloth having a width of 50 cm and a length of 250 cm was wound thereon, and a glass fiber cloth having a width of 50 cm and a length of 50 cm was wound thereon.
25 g of the titanium fiber was wound to form a first layer. The second layer is
A glass fiber cloth with a width of 50 cm and a length of 70 cm, and a width of 50 cm
carbon fiber cloth of 300 cm in length, glass fiber cloth of 50 cm in width and 100 cm in length, and 0.05 mm in diameter
40 g of the titanium fiber was wound on the first layer in this order. The third layer includes a glass fiber cloth having a width of 50 cm and a length of 120 cm, a carbon fiber cloth having a width of 50 cm and a length of 330 cm, a glass fiber cloth having a width of 50 cm and a length of 140 cm, and 55 g of titanium fiber having a diameter of 0.05 mm. It was formed by winding on the second layer in order. A platinum wire having a diameter of 0.2 mm was connected to each carbon fiber cloth and titanium fiber layer to form a lead wire. The carbon fiber cloth of each layer is
Polyaniline was adhered to the surface by an electrolytic polymerization method at about 3% of the weight of the carbon fiber. Distilled water 15 is used as the water 11 to be treated.
1, a mixture of 5.25 g (0.035%) of sodium carbonate and 750 g (5%) of factory wastewater containing general bacteria was prepared. This treated water was circulated in the same manner as in Example 2. For water sampled at predetermined time intervals, the concentration of hydrogen peroxide and the number of bacteria (the number of colonies) as in Example 2
Was measured.

[0041]

[Table 3]

As is apparent from Table 3 above, when titanium fibers are used for the anode, the surface area can be reduced even with a smaller weight (about 1/5) than that of a porous plate-shaped electrode using the same titanium material conventionally used. (Approximately 6.5 times per unit weight), and the current easily flows. As a result, the amount of generated hydrogen peroxide increases (6 to 12 times), and the disinfection effect is greatly improved.

[0043]

According to the present invention, the energy cost is high in a conventional method of disinfecting water, such as a boiling method, a method of adding a disinfectant such as chlorine or hydrogen peroxide, or an electrolytic disinfection method. Of course, problems such as the need for a large amount of disinfectant to be injected, the disinfectant being harmful to the human body in some cases, the danger of handling the disinfectant, and the difficulty of reliably disinfecting at low voltage are of course solved. That,
According to the suggestion of the present inventors, water to be treated is supplied between an anode and a cathode of a carbon fiber mat having polyaniline adhered to the surface thereof and an anode having a porous plate shape between the cathode and the anode. The efficiency of the electrode reaction in the method of sterilizing water for passing water is improved, and further energy saving and cost reduction in the sterilization of water can be realized. Further, if the aggregate of titanium fibers is used as the anode, there is an advantage that the structure of the anode can be arbitrarily selected to various structures as required.

[Brief description of the drawings]

FIG. 1 is a diagram showing the function of polyaniline in the sterilization treatment method of the present invention.

FIG. 2 is a schematic cross-sectional view of an example of an electrolytic cell according to the first embodiment of the sterilization treatment device of the present invention.

FIG. 3 is a schematic cross-sectional view of an example of an electrolytic cell according to a second embodiment of the sterilization apparatus of the present invention.

FIG. 4 is a schematic cross-sectional view of an example of an electrolytic cell according to a third embodiment of the sterilization apparatus of the present invention.

FIG. 5 is a schematic cross-sectional view of an example of an electrolytic cell according to a fourth embodiment of the sterilization apparatus of the present invention.

FIG. 6 is a schematic cross-sectional view of an example of an electrolytic layer according to a fifth embodiment of the sterilization apparatus of the present invention.

FIG. 7 is a schematic plan sectional view of an example of an electrolytic layer according to a fifth embodiment of the sterilization apparatus of the present invention.

FIG. 8 is an enlarged view of a portion A in FIG. 7;

FIG. 9 is a conceptual diagram illustrating a method for manufacturing a spiral electrode unit in an example of an electrolytic layer according to a fifth embodiment of the sterilization apparatus of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Electrolyzer 2 Cylindrical tank main body 3 Cylindrical cathode 4 Cylindrical anode 5 Inlet 6 Outlet 7 Electrode terminal 8 Disc separator 9 Disc porous plate 10 Disc filter 11 Water to be treated 12 Water tank to be treated DESCRIPTION OF SYMBOLS 13 Hose 14 Pump 15 Hose 21 Electrolyte tank 22 Cylindrical tank main body 23 Cylindrical cathode 24 Cylindrical anode 25 Inlet 26 Outlet 27 Electrode terminal 28 Cylindrical separator 29 Core material consisting of cylindrical porous material 31 Electrolyte tank 32 Box shape Tank body 33 Sheet-shaped cathode 34 Sheet-shaped anode 35 Inlet 36 Discharge port 37 Electrode terminal 38 Sheet-shaped separator 41 Electrolyte tank 42 Cylindrical tank body 43 Annular cathode 44 Annular anode 45 Inlet 46 Outlet 47 Electrode terminal 48 Annular separator 49 Core 51 composed of a cylindrical porous body 51 Electrolytic tank 52 Box-shaped tank main body 53 Cathode 54 Anode 55 Inlet 56 Outlet 57 Electrode terminal 58 Separator 59 Core material made of cylindrical porous body A Enlarged portion X Plate electrode unit Y Cylindrical electrode assembly Z Spiral electrode unit

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI C02F 1/50 560 C02F 1/50 560F

Claims (7)

[Claims] 1. A treatment water is introduced into an electrolytic cell provided with an anode and a cathode made of a conductive porous body having polyaniline adhered to the surface, and intermittent or continuous between the cathode and the anode. A method for disinfecting the microorganisms contained in the water to be treated by reducing the dissolved oxygen contained in the water to be treated and generating superoxide by passing the electric current while passing through, A method of sterilizing water for use, comprising using an aggregate of titanium fibers as the anode. 2. The apparatus used in the method for sterilizing water according to claim 1, wherein the tank body has an inlet and an outlet for the water to be treated, and the to-be-processed water flows from the inlet to the outlet. In order to be in contact with water, a cathode made of a conductive porous body having polyaniline adhered to the surface thereof, and an electrolytic tank provided with an anode made of an aggregate of titanium fibers in the tank body,
A sterilization apparatus comprising: a power supply for applying current to the anode and the cathode; and a facility for supplying the water to be treated to the electrolytic cell. 3. An electrolytic cell, wherein an inlet and an outlet for water to be treated are provided in the tank body at positions separated from each other, so that the water to be treated flowing from the inlet to the outlet is successively passed through and makes contact. A cathode made of a conductive porous body having polyaniline adhered to the surface on the inlet side in the tank body, and an anode made of an aggregate of titanium fibers on the outlet side in the tank body. The sterilization apparatus according to claim 2, wherein 4. An electrolytic cell comprising: an inlet for water to be treated in a tank main body; and a cylindrical core made of a porous material in the tank main body.
The core hollow portion is provided so as to communicate with the inlet, and on the outer periphery of the cylindrical core material, a cylindrical cathode made of a conductive porous body having polyaniline adhered to the surface thereof, and a cylindrical separator,
3. A cylindrical anode comprising a collection of titanium fibers is arranged to form a cylindrical electrode pair, and the tank body is provided with an outlet for the water to be treated flowing out of the cylindrical electrode pair. The sterilization treatment device according to the above. 5. An electrolytic cell having an inlet and an outlet for water to be treated in a tank main body, and inside the tank main body, via a thin plate separator to both surfaces of a thin plate anode made of an aggregate of titanium fibers. A plate-shaped electrode unit integrating a thin plate-shaped cathode made of a conductive porous body having polyaniline adhered to the surface thereof,
3. The sterilization apparatus according to claim 2, wherein the water to be treated is separated from each other so as to flow in a meandering manner between the plate-shaped electrode units. 6. An electrolytic cell, wherein an electrolytic cell is provided with an inlet for water to be treated in a cell main body, and a cylindrical core material made of a porous material is provided in the cell main body.
The hollow core is provided so as to communicate with the inlet, and an annular anode made of an aggregate of titanium fibers, an annular separator, and a conductive porous body having a polyaniline film adhered to the surface thereof are provided on the outer periphery of the cylindrical core material. An annular cathode composed of a body is laminated along the longitudinal direction of the tubular core material to form a tubular electrode assembly, and drainage of the for-treatment water flowing out of the tubular electrode assembly into the tank body. The sterilization apparatus according to claim 2, further comprising an outlet. 7. An electrolytic cell comprising: a tank main body having an inlet for water to be treated; and a cylindrical core material made of a porous material,
The core hollow portion is provided so as to communicate with the introduction port, and the outer periphery of the cylindrical core material, an anode made of an aggregate of titanium fibers, a separator, and a conductive porous body having a polyaniline film adhered to the surface. The sterilization apparatus according to claim 2, wherein a spirally wound electrode unit is formed by winding a laminate of the cathode and the cathode, and the tank body is provided with an outlet for the water to be treated flowing out of the spirally wound electrode unit.