JP2003311275A - Electric deionization apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric deionization apparatus which has simple structure and can be easily manufactured. <P>SOLUTION: A cation exchange membrane 3 and an anion exchange membrane 4 are arranged between a cathode 1 and an anode 2. A concentrating chamber and cathode chamber 5 is formed between the cathode 1 and the cation exchange membrane 3. A concentrating chamber and anode chamber 6 is formed between the anode 2 and the anion exchange membrane 4. A desalting chamber 7 is formed between the cation exchange membrane 3 and the anion exchange membrane 4. The concentrating chamber and cathode chamber 5 and the concentrating chamber and anode chamber 6 are respectively formed of a recess 11 of a plate 10 and of a recess 21 of a plate 20. Mesh-shaped membrane electrodes 1, 2 are respectively formed by sputtering or the like at bottom surfaces of the recesses 11, 21. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric deionization apparatus, and more specifically, deionized water (production water) per unit time.
The present invention relates to an electric deionization apparatus suitable when the amount of produced water is small.

[0002]

2. Description of the Related Art In a conventional electric deionization apparatus, a plurality of cation exchange membranes and anion exchange membranes are alternately arranged between electrodes (anode and cathode) to alternate a desalting chamber and a concentrating chamber. It is formed and has a structure in which a desalting chamber is filled with an ion exchange resin. In this electric deionization device, the water to be treated is caused to flow into the desalting chamber while applying a voltage between the anode and the cathode, and the concentrated water is circulated to the concentration chamber to remove impurity ions in the water to be treated. , To produce deionized water.

[0003]

The above-mentioned conventional electric deionization apparatus has a complicated structure in which a large number of frames, spacers and ion exchange membranes are alternately laminated and end plates are laminated.

Further, in the conventional electric deionization apparatus, a plurality of deionization chambers and concentration chambers are alternately formed between the cathode and the anode, so that the electric resistance between the cathode and the anode is increased. It is large and the applied voltage between both electrodes is high. Further, in the anode electrode chamber of the conventional electric deionization apparatus, since the electrode area is large, the amount of oxidants such as chlorine generated is large.

The present invention provides an electric deionization device having a simple structure, a low applied voltage between electrodes, and a reduced amount of chlorine and the like generated in the anode electrode chamber. With the goal.

[0006]

In the electric deionization apparatus of the present invention (claim 1), one cation exchange membrane and one anion exchange membrane are disposed between the cathode and the anode, and the cathode and the cation are placed. A concentration chamber / cathode chamber is provided between the exchange membrane and a concentration chamber / anode chamber between the anode and anion exchange membrane, and a desalting chamber is provided between the cation exchange membrane and anion exchange membrane. An electric deionization apparatus provided, wherein the deionization chamber is filled with an ion exchanger, wherein the concentration chamber and the cathode chamber are
For the cathode chamber plate, the surface facing the cation exchange membrane is a recess, and the concentrating chamber and the anode chamber are for the anode chamber whose surface facing the anion exchange membrane is a recess. It is characterized in that it is constituted by the recess of the plate.

In such an electric deionization apparatus of the present invention, the deionization chamber is one chamber, and the concentration chamber also serving as the anode chamber and the concentration chamber also serving as the cathode chamber are provided on both sides of the deionization chamber. Since they are arranged, the distance between the electrodes is small and the applied voltage between the electrodes is low. In the present invention, the desalting chamber is one chamber, and the amount of water produced per unit time is small, but it can be sufficiently used for small-scale experiments, small-scale fuel cells, and the like.

In the electric deionization apparatus of the present invention, each electrode chamber also serving as the concentrating chamber is constituted by the recess of the plate whose surface facing the ion exchange membrane is a recess, The chamber structure is simple, and the electric deionization apparatus is easy to assemble.

In the present invention, the electrodes are preferably provided along the bottom surface of the recess of the plate. As this electrode, a separate plate-shaped electrode plate, for example, a thin plate made of titanium plated with platinum may be attached to the bottom of the recess,
It is preferably in the form of a film formed by a vapor phase or liquid phase film forming method.

In the present invention, the generation of an oxidizing agent such as chlorine in the anode electrode chamber can be reduced by reducing the electrode area. In order to reduce the electrode area, it is preferable to provide an electrode on the bottom surface of the recess in a mesh shape, or to provide unevenness on the bottom surface of the recess, and to provide the electrode only on the recessed portion of this unevenness.

[0011]

DETAILED DESCRIPTION OF THE INVENTION Embodiments will be described below with reference to the drawings. FIG. 1 is a schematic vertical sectional view of an electric deionization apparatus according to an embodiment. FIG. 2 is an exploded perspective view of this electric deionization apparatus.

As shown in FIG. 1, a cation exchange membrane 3 and an anion exchange membrane 4 are arranged one by one between the cathode 1 and the anode 2, and between the cathode 1 and the cation exchange membrane 3 a concentrating chamber and a cathode are also provided. A chamber 5 is formed, a concentrating chamber / anode chamber 6 is formed between the anode 2 and the anion exchange membrane 4, and a desalting chamber 7 is formed between the cation exchange membrane 3 and the anion exchange membrane 4.

In this embodiment, in order to form the concentrating chamber / cathode chamber 5 and the concentrating chamber / anode chamber 6, each of the recesses 1 is formed.
The plates 10 and 20 with 1, 21 are used, and the rectangular frame 30 is used to form the desalting chamber 7.

The recesses 11 and 21 are the plates 1 respectively.
It is a rectangular one that is recessed from 0, 20 facing plate surfaces. The recess 11 faces the cation exchange membrane 3, and the recess 2
1 faces the anion exchange membrane 4. A cathode 1 and an anode 2 are provided on the bottom surfaces of the recesses 11 and 21. In this embodiment, as shown in FIG. 2, the cathode 1 and the anode 2 are provided in a mesh shape.

In this embodiment, a water passage hole 12 for the cathode electrode water is provided along the lower side of the plate 10, and a water passage hole 13 for the concentrated water and the cathode electrode water is provided along the upper side of the plate 10. There is. Each of the water passage holes 12 and 13 is provided with a concentrating chamber / cathode chamber 5 through a nozzle portion including a plurality of vertical holes.
It communicates with the inside.

Further, a water passage hole 22 for the anode electrode water is provided along the lower side of the plate 20, and a water passage hole 23 for the concentrated water / anode electrode water is provided along the upper side of the plate 20. Each of the water passage holes 22 and 23 communicates with the inside of the concentrating chamber / anode chamber 6 through a nozzle portion composed of a plurality of vertical holes.

In the frame 30, a raw water passage hole 31 is provided along the upper side, and a deionized water take-out hole 32 is provided along the lower side. Water passage holes 31, 3
2 communicates with the inside of the desalination chamber 7 through nozzles each having a plurality of vertical holes.

In order to form the cathode 1 and the anode 2,
Although a mesh-shaped conductor may be attached to the bottom surfaces of the recesses 11 and 21, it is preferable to form a mesh-shaped film by a vapor phase or liquid phase film formation method. The thickness of the formed film is, for example, about 0.5 to 10 μm, but is not limited to this.

Examples of such a film forming method include vacuum deposition, sputtering, liquid phase plating and the like. Specifically, the mesh-shaped electrode can be formed by subjecting the bottom surface of the recess of the polypropylene plate to a mesh-like surface treatment such as plasma and vacuum depositing platinum to a thickness of about 1 μm.

In order to form the mesh-shaped electrode, a mesh type (oblique grid type) recess is provided on the bottoms of the recesses 11 and 21, and a film is formed only on the recesses on the bottom of the recess to form a mesh. Electrodes may be formed.

The plate 10, the frame 30, and the plate 20 are laminated between them with the cation exchange membrane 3 and the anion exchange membrane 4 interposed therebetween, and tightened with bolts or the like to construct the structure of the electric deionization apparatus. A holding plate may be arranged outside the plates 10 and 20 to tighten the laminated body, but when the plates 10 and 20 are made of a high-strength material, the holding plate is not necessary.

The plates 10 and 20 may be made of synthetic resin such as polypropylene, but the material is not limited to this. The plates 10 and 2
By manufacturing 0 by injection molding of synthetic resin, cost reduction can be achieved.

A cation exchange resin 8 is provided in each of the cathode chamber 5 and the anode chamber 6 which also serve as a concentrating chamber in the electric deionization apparatus.
Is filled. The ion exchange resin filled in the cathode chamber 5 and the anode chamber 6 may be an anion exchange resin or a mixture of an anion exchange resin and a cation exchange resin, but from the viewpoint of resin strength, the cation exchange resin. Is preferably used. The desalting chamber 7 is filled with a cation exchange resin 8 and an anion exchange resin 9 in a mixed state.

In the electric deionization apparatus thus constructed, the raw water is introduced into the desalting chamber 7 while a voltage is applied between the cathode 1 and the anode 2 and is taken out as deionized water. Cathode electrode water is circulated in the concentration chamber / cathode chamber 5, and anode electrode water is circulated in the concentration chamber / anode chamber 6. Cations in the raw water pass through the cation exchange membrane 3, are mixed with the cathode electrode water, and are discharged. Anions in the raw water permeate the anion exchange membrane 4, mix with the anode electrode water, and are discharged.

In this electric deionization apparatus, only one desalting chamber 7, one concentrating chamber / anode chamber 6 and one concentrating chamber / cathode chamber 5 are arranged between the cathode 1 and the anode 2. Cage,
The distance between the cathode 1 and the anode 2 is small. Therefore, the electrode 1,
Even if the applied voltage between the two is low, a sufficient current can be passed between the electrodes 1 and 2 for deionization.

Since the electrode chamber also serves as the concentrating chamber, the electric conductivity of the electrode water is high. This also allows sufficient current to flow between the electrodes 1 and 2 even when the applied voltage between the electrodes 1 and 2 is low.

The flow direction of water in the electrode chambers / concentration chambers 5 and 6 may be parallel flow water with the desalting chamber or flow water as shown in the drawing, but in any case, upward flow water is preferable. this is,
In each of the electrode chambers / concentration chambers 5 and 6, H ₂ ,
This is because a gas such as O ₂ is generated, so that water is passed in an upward flow to accelerate the discharge of the gas and prevent a drift.

In the present invention, as the electrode water to be passed to the concentrating chamber / anode chamber and the concentrating chamber / cathode chamber, it is desirable to branch raw water and independently pass water to each concentrating chamber / electrode chamber. . According to this water flow system, unlike the conventional case where one electrode chamber outflow water is used as the other electrode water, the ionic species that have moved from the desalting chamber to each concentrating chamber / electrode chamber do not associate with each other. , Scale is less likely to occur.

In this embodiment, the electrodes 1 and 2 have a mesh shape, and the electrode surface area is small. Therefore, the amount of the oxidizing agent such as chlorine generated in the concentration chamber / anode chamber 6 can be reduced.

[0030]

As described above, the electric deionization apparatus of the present invention has a simple structure, is easy to manufacture, and requires a low applied voltage. Further, according to the present invention, it is possible to reduce the electrode area and reduce the generation amount of the oxidizing agent such as chlorine.

[Brief description of drawings]

FIG. 1 is a schematic vertical sectional view of an electric deionization apparatus according to an embodiment.

FIG. 2 is an exploded perspective view of an electric deionization apparatus.

[Explanation of symbols]

1 cathode 2 anode 3 Cation exchange membrane 4 Anion exchange membrane 5 Concentration chamber and cathode chamber 6 Concentration chamber and anode chamber 7 Desalination room 8 Cation exchange resin 9 Anion exchange resin 10, 20 plates 11,21 recess 30 frames

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Masayuki Miwa             Kurita, 3-4-3 Nishi-Shinjuku, Shinjuku-ku, Tokyo             Industry Co., Ltd. F-term (reference) 4D006 GA17 HA47 JA07A JA30Z                       JA41A JA42A JA43A MA13                       MA14 PA01 PB02                 4D061 DA01 DB13 DB14 EA09 EB01                       EB04 EB13 EB19 EB30 EB35                       FA08                 4K021 BA01 BA03 CA11 DB03 DB12                       DB31 DB36 DC15

Claims (5)

[Claims] 1. A cation exchange membrane and an anion exchange membrane are arranged one by one between a cathode and an anode, and a concentrating chamber and a cathode chamber are provided between the cathode and the cation exchange membrane. A concentration chamber and an anode chamber are provided between the ion exchange membrane and the cation exchange membrane, and a desalting chamber is provided between the cation exchange membrane and the anion exchange membrane. An ion apparatus, wherein the concentrating chamber / cathode chamber is constituted by the recess of a plate for a cathode chamber, the surface facing the cation exchange membrane being a recess, and the concentrating chamber / anode chamber comprises the anion. An electric deionization device, characterized in that the surface facing the exchange membrane is formed by the recess of the plate for the anode chamber, which is a recess. 2. The electric deionization apparatus according to claim 1, wherein electrodes are provided along the bottom surface of the recess of each plate. 3. The electric deionization apparatus according to claim 2, wherein the electrode is in the form of a film formed by a vapor phase or liquid phase film forming method. 4. The electric deionization device according to claim 2, wherein the bottom surface of the recess is an uneven surface, and the electrode is provided only in the recess of the uneven surface. 5. The electric deionization device according to claim 2, wherein the electrode is formed in a mesh shape.