JP4951830B2 - Electrical deionizer - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an electrical deionization apparatus, and more particularly to an electrical deionization apparatus having an improved configuration of a demineralization chamber.
[0002]
[Prior art]
The electrical deionization device alternately forms a plurality of cation exchange membranes and anion exchange membranes between the electrodes to alternately form a desalting chamber and a concentration chamber, and the desalting chamber is filled with an ion exchanger. The configuration is as follows. In this electrical deionization apparatus, while applying the voltage between the anode and the cathode, the treated water is allowed to flow into the desalting chamber, and the concentrated water is allowed to flow into the concentrating chamber to remove impurity ions in the treated water, Produces deionized water.
[0003]
FIG. 2 is an exploded view showing a basic configuration of a plate-and-frame type electrical deionization apparatus.
[0004]
A cathode electrode plate 2 is disposed along the cathode-side end plate 1, and a frame-like cathode spacer 3 is superimposed on the peripheral edge of the cathode electrode plate 2. On the cathode spacer 3, a cation exchange membrane 4, a frame frame 5 for forming a desalting chamber, an anion exchange membrane 6 and a frame frame 7 for forming a concentration chamber are superposed in this order. A large number of the cation exchange membrane 4, the frame-like frame 5 for forming a desalting chamber, the anion exchange membrane 6, and the frame-like frame 7 for forming a concentration chamber are superposed as a unit. That is, the film 4, the frame 5, the film 6, and the frame 7 are laminated repeatedly in succession. An anode electrode plate 9 is overlaid on the final anion exchange membrane 6 via a frame-like anode spacer 8, and an anode side end plate 10 is overlaid thereon to form a laminate. This laminate is tightened with bolts or the like.
[0005]
The inner space of the desalination chamber frame 5 is a desalination chamber, and this desalination chamber is filled with an ion exchanger 5R such as an ion exchange resin. The inside of the concentration chamber frame 7 is a concentration chamber. A mesh spacer or the like is disposed in the concentration chamber.
[0006]
In such an apparatus, a direct current is passed between the anode 9 and the cathode 2 and water to be treated (raw water) is passed through the water to be treated inflow line 11 into the desalting chamber, and the concentrated water is concentrated. Water is passed through the water inflow line 12 into the concentration chamber 8. The treated water that has flowed into the demineralization chamber flows down the packed bed of ion exchange resin. At that time, impurity ions in the treated water are removed to form deionized water, which flows out through the deionized water outflow line 13. To do.
[0007]
On the other hand, the concentrated water passed through the concentration chamber receives impurity ions moving through the ion exchange membranes 4 and 6 when flowing down the concentration chamber, and the concentrated water outflow line as concentrated water that has concentrated the impurity ions. 14 flows out. Electrode water is circulated through the electrode chambers via introduction lines 15 and 16 and extraction lines 17 and 18, respectively.
[0008]
By the way, Japanese Patent Publication No. 4-72567 discloses an electrical deionization apparatus in which partition ribs are provided in the demineralization chamber in the vertical direction and the demineralization chamber is divided into small chambers that are long in the vertical direction. Thus, in the electrical deionization apparatus in which the desalination chamber is divided into elongated chambers by ribs and each chamber is filled with an ion exchange resin, the demineralization chamber is locally biased from the entrance to the exit of the desalination chamber. Channeling phenomenon in which water flows is prevented.
[0009]
[Problems to be solved by the invention]
In the above-mentioned electrical deionization apparatus of Japanese Patent Publication No. 4-72567, the desalting chamber is divided into vertically elongated narrow chambers, and the flow of water in the left-right direction is blocked by the ribs. The contact efficiency with the ion exchange resin is poor. Furthermore, the ion exchange resin is compressed in the lower part of the small chamber, and there is a disadvantage in that there is a gap in the upper part and the filling rate of the ion exchange resin tends to be low.
[0010]
An object of the present invention is to overcome such various disadvantages, and to provide an electrical deionization device having high contact efficiency between water and an ion exchanger and high packing density of the ion exchanger and the like.
[0011]
[Means for Solving the Problems]
The electrical deionization apparatus of the present invention alternately forms a plurality of cation exchange membranes and anion exchange membranes between electrodes to alternately form a desalting chamber and a concentrating chamber, and performs ion exchange in the desalting chamber. An electrical deionization apparatus that fills the body, allows water to be treated to flow into the desalting chamber, and allows the concentrated water to flow into the concentration chamber, between the cation exchange membrane and the anion exchange membrane. In an electrical deionization apparatus in which a substantially rectangular frame-shaped frame for forming a desalting chamber is interposed, the frame-shaped frame is provided with a first desalination chamber on one half side of the long side of the rectangular shape. , a second electrical deionization apparatus desalting compartment is that provided in the other half side, the inlet of the water to be treated to each desalting compartment is provided at an end portion side in the long side direction And the outflow port of the to-be-processed water from each desalination chamber is provided in the center side of the long side direction, It is characterized by the above- mentioned.
[0012]
In such an electrical deionization apparatus, the manufacturing cost of the electrical deionization apparatus can be reduced by increasing the size of the frame-shaped frame.
[0013]
In other words, the frame-like frame is often manufactured by plastic injection molding, but the manufacturing cost is not proportional to its size, and the cost increases as it increases within a reasonable range that can be molded by a molding machine. Reduced. For example, in the case of a frame-like frame having the same thickness, one 500 mm × 1000 mm is less expensive than two 500 mm × 500 mm. Further, the manufactured frame-shaped frame requires a process of attaching an ion exchange membrane by adhesive tape or high frequency welding, but the number of processed sheets is halved, so that the cost can be reduced.
[0014]
Moreover, in the electrical deionization apparatus of the present invention, when the longitudinal direction of the frame-like frame is set as the vertical direction, the demineralization chamber is divided into two upper and lower chambers. Shorter. For this reason, the ion exchanger becomes difficult to be compressed in the lower part of each desalting chamber, the filling rate of the ion exchanger is maintained high, and the desalting efficiency is improved. The vertical length of each desalting chamber is preferably about 250 to 450 mm.
[0015]
In the present invention, the inlet of the water to be treated to each desalting chamber is provided on the end side in the long side direction, and the outlet of the water to be treated from each desalting chamber is provided on the center side in the long side direction. is not that.
[0016]
According to such an electrical deionization apparatus, the region to which a high introduction water pressure is applied is on both end sides in the long side direction. On both ends, a fastening member for fastening the frame-shaped frame, the cation exchange membrane, and the anion exchange membrane laminate is disposed, and sufficiently resists the pressure in the anti-lamination direction (opposite to the lamination direction) applied by water pressure. can do. Since the water pressure in the vicinity of the outlet from the desalting chamber is lower than that in the vicinity of the inlet, the pressing force in the anti-stacking direction applied to the laminate is low. In addition, since the outlet of each desalting chamber is the central side in the long side direction, the water pressure near the outlet on the central side in the long side direction of each desalting chamber becomes substantially equal, and the pressure in the anti-stacking direction is also It is almost equivalent.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments will be described with reference to the drawings. FIG. 1 is a perspective view of a frame frame for a desalination chamber of an electrical deionization apparatus according to an embodiment.
[0018]
The frame-like frame 20 has a rectangular shape, and a first desalting chamber 21 and a second desalting chamber are provided on one half side (the upper half side in the figure) and the other half side (the lower half side in the figure), respectively. A salt chamber 22 is formed. Introducing ports 31 and 32 of water to be treated are arranged in the upper part of the desalting chamber 21 and the lower part of the desalting chamber 22, respectively. Outflow ports 41 and 42 for desalted water from which the water to be treated has been desalted are provided at the lower portion of the desalting chamber 21 and the upper portion of the desalting chamber 22, respectively.
[0019]
These inlets 31, 32 and outlets 41, 42 are formed so as to partially expand the desalting chambers 21, 22 upward or downward, respectively.
[0020]
Above the desalting chamber 21 and below the desalting chamber 22, there are provided water channel forming openings 51 and 52 for guiding concentrated water to the respective concentration chambers.
[0021]
A partition-shaped horizontal crosspiece 54 that partitions the desalting chambers 21 and 22 is provided with an opening 53 for forming a water channel for extracting concentrated water from each concentration chamber.
[0022]
By arranging an anion exchange membrane on one side of the frame-like frame 20 and a cation exchange membrane on the other side, the desalting chambers 21 and 22 are partitioned. A frame-like frame (not shown) of the same size is arranged to form a concentrating chamber adjacent to the desalting chambers 21, 22. As in FIG. 2, a cation exchange membrane and a frame for forming a desalting chamber A large number of frames, anion exchange membranes, and a frame-like frame for concentrating chamber formation are laminated in this order, so that a number of desalting chambers and concentrating chambers are alternately formed. As in FIG. 2, end plates are arranged on both ends in the stacking direction of the stacked body to form electrode chambers. A cathode plate is disposed in the electrode chamber on the cathode side, and an anode plate is disposed in the electrode chamber on the anode side. This laminated body is clamped in the stacking direction by a tightening member.
[0023]
The frame for the concentrating chamber is not shown, but preferably has a first concentrating chamber and a second concentrating chamber having a size facing the first and second desalting chambers 21 and 22. . The concentrated water that has passed through the opening 51 is introduced into the upper first concentrating chamber, and the concentrated water that has passed through the opening 52 is introduced into the lower second concentrating chamber. Concentrated water that has received ions from the desalting chamber 21 or 22 is taken out from the lower portion of the first concentrating chamber and the upper portion of the second concentrating chamber through the openings 53, respectively.
[0024]
The electrodeionization apparatus having the frame-like frame 20 is installed so that the long side direction of the frame-like frame is the vertical direction. In this case, as described above, the vertical length of the desalting chambers 21 and 22 is preferably set to 250 to 450 mm, so that there is almost no compression of the ion exchanger in the lower portion of each of the desalting chambers 21 and 22. Efficient desalting is performed. Further, since the flow rate per frame frame is large, the processing flow rate of the entire electrical deionization apparatus is also large. Further, the number of frame-like frames can be reduced as compared with the conventional apparatus having the same processing flow rate, and the manufacturing cost is reduced.
[0025]
In particular, in this embodiment, the inlets 31 and 32 of the water to be treated having a high water pressure are arranged above and below the frame-like frame, and the water pressure of the water to be treated that presses the laminate in the anti-lamination direction. It can fully compete and the durability of the device is also good.
[0026]
【Effect of the invention】
As described above, according to the present invention, it is possible to increase the processing flow rate of the electrical deionization apparatus, reduce the manufacturing cost, and to improve the durability of the apparatus.
[Brief description of the drawings]
FIG. 1 is a perspective view of a frame-like frame used in an electrical deionization apparatus according to an embodiment.
FIG. 2 is an exploded perspective view of a conventional electrical deionization apparatus.
[Explanation of symbols]
4 Cation Exchange Membrane 5 Frame-shaped Frame 5R Ion Exchanger 6 Anion Exchange Membrane 20 Frame-shaped Frame 21 First Desalting Chamber 22 Second Desalting Chambers 31, 32 Inflow Water 41, 42 Flow of Demineralized Water Exit

Claims (3)

A plurality of cation exchange membranes and anion exchange membranes are alternately arranged between the electrodes to alternately form a desalting chamber and a concentrating chamber. The desalting chamber is filled with an ion exchanger, and the desalting chamber is covered. An electrical deionization device for passing treated water and passing concentrated water to the concentration chamber,
In the electrical deionization apparatus in which a substantially rectangular frame-shaped frame for forming a desalting chamber is interposed between the cation exchange membrane and the anion exchange membrane,
Framelike frame, first desalting compartment is provided on one half side of the rectangular long side direction, and a second desalting compartment is not that electrical deionization apparatus provided other half side ,
An inlet for treated water to each desalting chamber is provided on the end side in the long side direction, and an outlet for treated water from each desalting chamber is provided on the center side in the long side direction. An electrical deionization device. Oite to claim 1, as the concentration compartment, the a first concentrating chamber facing said first desalting compartment, a second concentrating chamber facing the second desalting compartment is provided An electrical deionization device. According to claim 1 or 2, electric deionization unit length of the first and second of the long side direction of the desalting compartment is characterized in that it is a 250～450Mm.

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