JP4168894B2 - Electric deionizer - Google Patents

Description

  The present invention relates to an electric deionization apparatus, and more particularly to an electric deionization apparatus suitable when the amount of deionized water (production water) produced per unit time is small.

A conventional electric deionization apparatus alternately forms a plurality of cation exchange membranes and anion exchange membranes between electrodes (anode and cathode) to alternately form a desalting chamber and a concentrating chamber. The chamber is filled with ion exchange resin. In this electric deionization apparatus, water to be treated is allowed to flow into the demineralization chamber while applying a voltage between the anode and the cathode, and the concentrated water is circulated through the concentration chamber to remove impurity ions in the water to be treated. Then, deionized water is produced (for example, JP-A-10-43554).
Japanese Patent Laid-Open No. 10-43554

I. In the conventional electric deionization apparatus, a water passage hole is provided in the spacer disposed between the cation exchange membrane and the anion exchange membrane, and both end plates of the electric deionization apparatus, and through this water passage hole, Although raw water, concentrated water, and electrode water are circulated in each chamber, the number of water holes is large, and the length of the frame and end plate has to be increased due to the arrangement of the water holes. .
The first object of the present invention is to make it possible to reduce the size of an electric deionization apparatus.

II. Since the conventional electric deionization apparatus is formed by alternately forming a plurality of demineralization chambers and concentration chambers between the cathode and the anode, the electric resistance between the cathode and the anode is large, and between the two electrodes. Applied voltage is high. In addition, the structure is complicated, and it takes time to manufacture.
A second object of the present invention is to provide an electric deionization apparatus that is simple in construction and easy to manufacture and that requires a low applied voltage.

III. When the end plate and the frame of the conventional electric deionization apparatus are made of synthetic resin, the synthetic resin has low heat resistance such as polypropylene and vinyl chloride. For this reason, it could not be arranged at a location with relatively high temperature (for example, a location adjacent to the fuel cell).
A third object of the present invention is to provide an electrical deionization apparatus that can be disposed at a location where the temperature is relatively high.

  The electric deionization apparatus of the present invention (Claim 1) includes a cation exchange membrane and an anion exchange membrane disposed between a cathode and an anode, respectively, held on a plate, and a cation exchange membrane disposed on the cathode side. Electric deionization, in which a demineralization chamber surrounded by a frame is provided between the anion exchange membrane disposed on the anode side, and an inflow path and an outflow path for electrode water are provided in each plate. In the apparatus, the plate and the frame are made of heat-resistant synthetic resin, and the inflow path and the outflow path are respectively connected to the cathode chamber and the anode chamber by going around the edge of the electrode plate constituting the cathode and the anode. It is characterized by being.

  In the electric deionization apparatus of the present invention, since the inflow path and the outflow path of the electrode water are provided so as to go around the edge of the electrode plate, the arrangement space of the inflow path and the outflow path is set in each chamber. The extension length on both sides in the longitudinal direction can be reduced.

  In this electric deionization apparatus, since the plate and the frame are made of a heat-resistant synthetic resin, even if the plate and the frame are arranged at a high comparative temperature, deformation of the plate and the frame or elution of the resin component from them can be prevented.

  In the electric deionization apparatus of the present invention (Claim 5), one cation exchange membrane and one anion exchange membrane are disposed between the cathode and the anode, respectively, and the concentration chamber serves as a space between the cathode and the cation exchange membrane. An electric deionization apparatus in which a cathode chamber is provided, a concentration chamber / anode chamber is provided between the anode and the anion exchange membrane, and a desalting chamber is provided between the cation exchange membrane and the anion exchange membrane The outer shell of the electric deionization apparatus is composed of a pair of half shells on the cathode side and the anode side that face each other and these half shells are made of a heat-resistant synthetic resin. The concentric surface of each half shell is provided with a recess, and the inside of the recess of the cathode side half shell is separated from the desalting chamber by the cation exchange membrane, and serves as the concentration chamber / cathode chamber. Inside the recess of the half shell is the anion The concentration chamber / anode chamber is separated from the desalting chamber by a membrane, and is formed of a heat-resistant synthetic resin between the cation exchange membrane and the anion exchange membrane, and has a frame surrounding the desalination chamber. It is characterized by being interposed.

  The electric deionization apparatus configured as described above has one demineralization chamber, and a concentration chamber also serving as an anode chamber and a concentration chamber also serving as a cathode chamber are arranged on both sides of the demineralization chamber. Therefore, the distance between the electrodes is small and the applied voltage between the electrodes is low. This electric deionization apparatus has one demineralization chamber and a small amount of water produced per unit time, but can be sufficiently put into practical use for small-scale experiments, small fuel cells, and the like.

  In addition, this electric deionization apparatus can be assembled by sandwiching a frame and one cation exchange membrane and one anion exchange membrane between a pair of half shells, and the structure and assembly are simple.

  Since the half shell and frame of this electric deionization device are made of heat-resistant synthetic resin, even if it is placed at a relatively high temperature, deformation of the half shell, frame, or elution of components from them is prevented. The

  In the electric deionization apparatus of the present invention (Claim 6), the first cation exchange membrane, the anion exchange membrane, and the second cation exchange membrane are arranged in this order between the cathode and the anode, A concentration chamber / cathode chamber is provided between the first cation exchange membrane and a desalting chamber is provided between the first cation exchange membrane and the anion exchange membrane, and the anion exchange membrane and the second cation exchange membrane. An electric deionization device in which a concentration chamber is provided between the membrane and an anode chamber is provided between the second cation exchange membrane and the anode, and the outer shell of the electric deionization device is The cathode and the anode are a pair of half shells that are overlapped facing each other. These half shells are made of heat-resistant synthetic resin, and each half shell is provided with a recess on the opposite surface. And the inside of the recess of the cathode-side half shell is the first capacitor. The concentration chamber / cathode chamber separated from the desalting chamber by an on-exchange membrane, and the anode chamber in which the recess of the anode-side half shell is separated from the concentration chamber by the second cation exchange membrane; A frame made of a heat-resistant synthetic resin and surrounding the desalting chamber is interposed between the first cation exchange membrane and the anion exchange membrane, and the anion exchange membrane and the second cation exchange membrane. A frame made of heat-resistant synthetic resin and surrounding the concentration chamber is interposed between the membrane and the membrane.

  The electric deionization apparatus configured as described above has one demineralization chamber, and a concentration chamber and a cathode chamber / concentration chamber are disposed on both sides of the demineralization chamber. The distance is small and the applied voltage between the electrodes is low. This electric deionization apparatus has one demineralization chamber and a small amount of water produced per unit time, but can be sufficiently put into practical use for small-scale experiments, small fuel cells, and the like.

  Further, this electric deionization apparatus can be assembled by sandwiching two frames, two cation exchange membranes and one anion exchange membrane between a pair of half shells. Simple.

  Since the half shell and frame of this electric deionization device are made of heat-resistant synthetic resin, even if it is placed at a relatively high temperature, deformation of the half shell, frame, or elution of components from them is prevented. The

  As the heat-resistant synthetic resin, syndiotactic polystyrene (SPS) or polyacetal resin is suitable.

  In these electric deionization apparatuses, electrode plates are arranged at the bottoms in the respective recesses so that the electrode water flows through the concentration chamber / cathode chamber, the concentration chamber / anode chamber or the anode chamber, respectively. It is preferable that each half shell is provided with an inflow path and an outflow path, and in particular, the inflow path and the outflow path each wrap around the edge of the electrode plate and are separated from the back surface of the electrode plate. It is preferable to extend to the outer surface of each half shell.

  By arranging the inflow path and the outflow path in this way, the length of the electric deionization apparatus can be reduced.

  According to the present invention, the length of the electric deionizer can be reduced. According to the present invention, it is possible to simplify the configuration of the electric deionization device or to reduce the applied voltage. The electric deionization apparatus of the present invention can also be arranged at a location where the temperature is relatively high.

  Hereinafter, embodiments will be described with reference to the drawings. FIG. 10 is a schematic longitudinal sectional view of an electrical deionization apparatus according to an embodiment of the present invention.

  One cation exchange membrane 3 and one anion exchange membrane 4 are arranged between a cathode (cathode electrode plate) 1 and an anode (anode electrode plate) 2, and a concentration chamber is provided between the cathode 1 and the cation exchange membrane 3. A cathode chamber 5 is formed, a concentration 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 concentration chamber / cathode chamber 5 and the concentration chamber / anode chamber 6, plates 10 and 20 with recesses 11 and 21 made of heat-resistant synthetic resin are used, respectively, and the desalination chamber 7. A square frame 30 made of a heat-resistant synthetic resin is used to form the frame.

  The recesses 11 and 21 are rectangular ones recessed from the opposing plate surfaces of the plates 10 and 20, respectively. The recess 11 faces the cation exchange membrane 3, and the recess 21 faces the anion exchange membrane 4. A cathode electrode plate 1 and an anode electrode plate 2 are provided on the bottom surfaces of the recesses 11 and 21.

  In this embodiment, a cathode electrode water inflow passage water passage hole 12 is provided in the lower portion of the plate 10, and a concentrated water / cathode electrode water outflow passage water passage hole 17 is provided in the upper portion of the plate 10. . Each of the water passage holes 12 and 17 extends in a direction perpendicular to the back surface of the cathode electrode plate 1 and faces the outer surface of the electric deionization apparatus. The water holes 12 and 17 are connected to the concentrating chamber / cathode chamber 5 around the edges 14 and 15 of the cathode electrode plate 1.

  Further, an inflow water hole 22 for inflow of anode electrode water is provided in the lower part of the plate 20, and an inflow hole 27 for outflow of concentrated water / anode electrode water is provided in the upper part of the plate 20. Each of the water passage holes 22 and 27 extends in a direction perpendicular to the back surface of the anode electrode plate 2 and faces the outer surface of the electric deionizer. The water holes 22 and 27 are connected to the concentrating chamber / anode chamber 6 through the edges 24 and 25 of the anode electrode plate 2.

  A relay chamber 33 for introducing raw water is provided at the upper portion of the frame 30, and raw water is introduced into the relay chamber 33 through the anion exchange membrane 4 and the water holes 32 and 31 provided at the upper portion of the plate 20. The The raw water flows from the relay chamber 33 into the desalting chamber 7 through a shallow wide groove-shaped raw water inlet 34. The water in the desalting chamber 7 flows into the relay chamber 36 from a shallow wide groove-shaped desalting water outlet 35 provided in the lower part of the frame 30, and further provided in the lower part of the anion exchange membrane 4 and the plate 20. It is taken out through the water holes 37 and 38.

  The frame 30 has a rectangular shape, and the desalting chamber 7 is formed in a shape that is hollowed out in the thickness direction except for its upper and lower portions. Only one desalting chamber 7 is provided in the frame 30. The desalting chamber 7 has a rectangular shape and extends in the longitudinal direction of the frame 30. Accordingly, the frame 30 has a rectangular frame shape in which the portion of the desalting chamber 7 penetrates in the thickness direction.

Width _{W 1} of the desalting compartment 7 is 20mm or less, preferably 5~20mm particularly 5 to 15 mm. A member for holding the ion exchanger is not arranged in the desalting chamber 7, and the desalting chamber 7 is a single rectangular parallelepiped-shaped empty chamber. When the width is 20 to 60 mm, a holding member such as a honeycomb may be provided.

  As shown in FIGS. 2 and 3, the relay chambers 33 and 36 are constituted by deep grooves that are recessed from the surface of the upper and lower portions of the frame 30 that overlap the anion exchange membrane 4. Each of the relay chambers 33 and 36 extends in the width direction of the frame 30, and the relay chambers 33 and 36 are substantially equal in width to the desalting chamber 7.

  The inflow port 34 and the outflow port 35 that connect the relay chambers 33 and 36 to the desalting chamber 7 are formed of wide shallow grooves formed on the surface of the frame 30 that overlaps the anion exchange membrane 4. The depths of the inlet 34 and the outlet 35 made of this shallow groove are smaller than the particle size of the ion exchange resin filled in the desalting chamber 7, and are usually about 0.1 to 0.3 mm. Is done.

  The size (width and height) of the recesses 11 and 21 of the plates 10 and 20 is the same as that of the desalting chamber 7, and the cathode chamber 5 and the anode chamber 6 also serving as the concentrating chamber are arranged to match the desalting chamber 7. Has been.

  The plate 10, the frame 30 and the plate 20 are laminated between them through the cation exchange membrane 3 and the anion exchange membrane 4, and are tightened with bolts or the like to constitute a structure of an electrical deionization apparatus. In order to fasten the laminated body, a press plate may be disposed outside the plates 10 and 20, but the press plate is not necessary when the plates 10 and 20 are made of a high-strength material.

  The plates 10 and 20 are preferably made of, for example, SPS or polyacetal resin, but the material is not limited to this.

  The concentration chamber / cathode chamber 5 and the anode chamber 6 inside the electric deionizer are each filled with a cation exchange resin. 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. Is preferably used. The desalting chamber 7 is filled with a cation exchange resin and an anion exchange resin, preferably in a mixed state at a ratio of cation exchange resin / anion exchange resin = 2/8 to 5/5.

  In the electric deionization apparatus configured in this way, raw water is introduced into the demineralization chamber 7 through the water passage hole 31 in a state where a voltage is applied between the cathode electrode plate 1 and the anode electrode plate 2. Demineralized water (deionized water) is taken out from the water hole 38. Cathode electrode water is passed through the concentrating chamber / cathode chamber 5 through the water holes 12, 17, and anode electrode water is passed through the concentrating chamber / anode chamber 6 through the water holes 22, 27. The cations in the raw water pass through the cation exchange membrane 3 and are mixed with the cathode electrode water and discharged. Anions in the raw water permeate through the anion exchange membrane 4 and enter the anode electrode water and are discharged.

  In this electric deionization device, the water passage holes 12, 17, 22, 27 are arranged so as to go around the end edges 14, 15, 24, 25 of the electrode plates 1, 2, so that the plate The length (height) H of 10, 20 and the frame 30 can be reduced. That is, since the water passage holes 12, 17, 22, and 27 are not provided in the portions extending upward and downward in FIG. 10 from the chambers 5, 6, and 7, the lengths of the plates 10, 20 and the frame 30 are as follows. That's how much shorter.

  Further, in this electric deionization apparatus, only one demineralization chamber 7, a concentration chamber / anode chamber 6 and a concentration chamber / cathode chamber 5 are provided between the cathode electrode plate 1 and the anode electrode plate 2, respectively. The distance between the cathode electrode plate 1 and the anode electrode plate 2 is small. Therefore, even if the applied voltage between the electrode plates 1 and 2 is low, a sufficient current can be passed between the electrode plates 1 and 2 to perform the deionization process.

  In addition, since the electrode chamber also serves as the concentration chamber, the electrical conductivity of the electrode water is high. This also allows a sufficient current to flow between the electrode plates 1 and 2 even if the applied voltage between the electrode plates 1 and 2 is low.

  In this electric deionization apparatus, since the plates 10 and 20 and the frame 30 are made of a heat-resistant synthetic resin, the electric deionization apparatus can be disposed at a relatively high temperature, for example, next to the fuel cell.

The direction of water flow in the electrode chambers / concentration chambers 5 and 6 may be the desalting chamber and the parallel circulating water or the counter-flowing water shown in the figure. This is because gas such as H ₂ , O ₂ , and Cl ₂ is generated in each electrode chamber / concentration chamber 5, 6 by direct current, so that water flows in an upward flow to promote gas discharge and prevent drift. It is.

  Embodiments of the inventions of claims 4 to 6 will be described below with reference to FIGS. 1 is an exploded perspective view of an electrical deionization apparatus according to an embodiment, FIGS. 2 and 3 are enlarged exploded perspective views of a part of the electrical deionization apparatus, and FIGS. 4 and 5 are half views. FIG. 6 is a longitudinal sectional view of the electric deionizer, FIG. 7 is a sectional view taken along line VII-VII in FIG. 6, and FIG. 8 is a line VIII-VIII in FIG. FIG. 9 is a sectional view taken along the line IX-IX in FIG.

  In FIG. 1, the cation exchange membrane and the anion exchange membrane are not shown. 2 and 3 show only a part of the electrode plate. FIGS. 4 (b) and 5 (b) are cross-sectional views taken along the line BB of each (a) figure.

  In this embodiment, the outer shell of the electric deionization apparatus is composed of a pair of substantially half-cylindrical half shells 50 and 50A made of heat-resistant synthetic resin. Between the half shells 50 and 50A, a frame 90 made of a heat-resistant synthetic resin, one cation exchange membrane 43 and one anion exchange membrane 44 are arranged.

  As shown in FIGS. 6 and 7, a cation exchange membrane 43 and an anion exchange membrane 44 are arranged one by one between a cathode (cathode electrode plate) 41 and an anode (anode electrode plate) 42 to exchange cation with the cathode 41. A concentration chamber / cathode chamber 45 is formed between the membrane 43, a concentration chamber / anode chamber 46 is formed between the anode 42 and the anion exchange membrane 44, and between the cation exchange membrane 43 and the anion exchange membrane 44. A desalting chamber 47 is formed.

  In this embodiment, in order to form the concentration chamber / cathode chamber 45 and the concentration chamber / anode chamber 46, the half shells 50 and 50A with the recesses 61 and 61A are used to form the desalting chamber 47, respectively. A square frame 90 is used.

  The recesses 61 and 61A are elongated rectangular shapes recessed from the opposing plate surfaces of the half shells 50 and 50A, respectively. The recess 61 faces the cation exchange membrane 43, and the recess 61A faces the anion exchange membrane 44. A cathode 41 and an anode 42 are provided on the bottom surfaces of the recesses 61 and 61A.

  On the bottom surfaces of the recesses 61, 61A, insertion holes 51, 51A for terminals (not shown) protruding from the back surfaces of the cathode electrode 1 and the anode electrode 42 are provided. A putty-like sealing material 49 (FIG. 7) is applied to the crossing corners between the side wall surfaces in the longitudinal direction of the recesses 61 and 61A and both side edges of the electrode plates 41 and.

  Around the recesses 61, 61A are shallow stepped recesses 60, 60A. The frame 90 engages with the recessed step portions 60 and 60A.

  In this embodiment, the cathode electrode water inflow passage water passage 62 is provided on the right end side of each figure of the half shell 50, and the concentrated water / cathode electrode water outflow passage water passage is provided on the left end side of the half shell 50. A hole 72 is provided. The water holes 62 and 72 communicate with the concentrating chamber / cathode chamber 45 through water channels 63 and 73, relay chambers 64 and 74, weirs 65 and 75, and relay chambers 66 and 76, respectively.

  In addition, an anode electrode water inflow passage water passage 62A is provided on the right end side of each figure of the half shell 50A, and an outflow passage water passage 72A for concentrated water and anode electrode water is provided on the left end side of the half shell 50A. It has been. The water holes 62A and 72A communicate with the concentrating chamber / anode chamber 46 through the water channels 63A and 73A, the relay chambers 64A and 74A, the weirs 65A and 75A, and the relay chambers 66A and 76A, respectively.

  A relay chamber 94 for introducing raw water is provided on the left end side of the frame 90 in the figure, and the water passage hole 81 provided in the half shell 50A and the water passage hole provided in the anion exchange membrane 44 are connected to the relay chamber 94. Raw water is introduced through The raw water flows from the relay chamber 94 into the desalting chamber 47 through the weir 93. Water in the desalination chamber 47 flows into the relay chamber 91 from a weir 92 provided on the right end side of the frame 90 in the drawing, and further, water passage holes 44a, 80 provided in the anion exchange membrane 4 and the half shell 50A. Is taken out through.

  As shown in FIG. 1, the frame 90 extends long in one direction, and a desalting chamber 47 is formed in a shape hollowed out in the thickness direction. Only one desalting chamber 47 is provided in the frame 90. The desalting chamber 47 has a rectangular shape and extends in the longitudinal direction of the frame 90. Accordingly, the frame 90 has an elongated ground shape. Ribs 97 are provided around both sides of the frame 90. The rib 97 is for pressing the ion exchange membranes 43 and 44 to achieve watertightness.

  The width of the desalting chamber 47 is 20 mm or less, preferably 5 to 20 mm, particularly 5 to 15 mm. A member for holding the ion exchanger is not disposed in the desalting chamber 47, and the desalting chamber 47 is a single rectangular parallelepiped-shaped empty chamber. When the width is 20 to 60 mm, a holding member such as a honeycomb may be provided.

  The thickness of the desalting chamber 47, that is, the thickness of the frame 90 is smaller than this width.

  As shown in FIGS. 1 to 3, the relay chambers 94 and 91 are constituted by deep grooves that are recessed from the surface overlapping the anion exchange membrane 44 on both ends in the longitudinal direction of the frame 90. The relay chambers 94 and 91 each extend in the width direction of the frame 90, and the relay chambers 94 and 91 are substantially equal in width to the desalting chamber 47.

  The inflow weir 93 and the outflow weir 92 that connect the relay chambers 94 and 91 to the desalting chamber 47 are formed by a wide shallow groove formed on the surface of the frame 90 that overlaps the anion exchange membrane 44. It has a canal space. The depth of the water channel space formed by this shallow groove is smaller than the particle size of the ion exchange resin filled in the desalting chamber 47, and is usually about 0.1 to 0.3 mm.

  In this embodiment, at the center in the width direction of the weirs 93 and 92, a rib extending in the direction connecting the relay chambers 94 and 91 and the desalting chamber 47 (longitudinal direction of the frame 90) (FIGS. 2 and 3). No. 92a) is provided. The top surface of the rib 92 a is flush with the surface of the frame 90 that overlaps the anion exchange membrane 4. The ribs 92a prevent the anion exchange membrane 4 from entering the shallow channel space.

  The width of the water channel space is preferably 60% or more, particularly 75% or more of the width of the desalting chamber 47.

  In addition, by providing this relay chamber 94, the raw water flowing in from the water flow holes 81 is evenly distributed throughout the width direction of the desalting chamber 47.

  The relay chambers 66, 76, 66A, 76A and the weirs 65, 75, 65A, 75A provided in the half shells 50, 50A have the same configuration as the relay chamber 33 and the inlet 34, respectively. Each of the water passage holes 12, 17, 22, and 27 faces the bottom surface of the groove-shaped water channels 63, 73, 63A, and 73A. Relay chambers 64, 74, 64A, and 74A are provided between these water channels 63, 73, 63A, and 73A and the weirs 65, 75, 65A, and 75A. These relay chambers 64, 74, 64A, and 74A have the same width as the weirs 65, 75, 65A, and 75A.

  The size (width and length) of the recesses 61, 61A of the half shells 50, 50A is the same as that of the desalting chamber 47, so that the cathode chamber 45 and the anode chamber 46, which are also used as a concentration chamber, match the desalting chamber 47. Has been placed.

  The half shells 50 and 50A are overlapped with each other through the cation exchange membrane 43, the frame 90, and the anion exchange membrane 44, and the outer periphery is fastened with a band, a wire, or the like to form a structure of an electric deionization apparatus. .

  The half shells 50 and 50A and the frame 90 are preferably made of, for example, SPS or polyacetal resin, but the material is not limited thereto.

  The concentration chamber / cathode chamber 45 and the anode chamber 46 in the electric deionizer are filled with a cation exchange resin 48, respectively. The ion exchange resin filled in the cathode chamber 45 and the anode chamber 46 may be an anion exchange resin or a mixture of an anion exchange resin and a cation exchange resin. Is preferably used. The desalting chamber 47 is filled with a cation exchange resin and an anion exchange resin, preferably in a mixed state at a ratio of cation exchange resin / anion exchange resin = 2/8 to 5/5.

  In the electric deionization apparatus configured as described above, raw water is introduced into the desalting chamber 47 from the water passage hole 81 in a state where a voltage is applied between the cathode 41 and the anode 42, and Remove demineralized water (deionized water). Cathode electrode water is circulated through the concentration chamber / cathode chamber 45, and anode electrode water is circulated through the concentration chamber / anode chamber 46. The cations in the raw water pass through the cation exchange membrane 43 and are mixed with the cathode electrode water and discharged. The anions in the raw water permeate through the anion exchange membrane 44, enter the anode electrode water, and are discharged.

  In this electric deionization apparatus, only one demineralization chamber 47, a concentration chamber / anode chamber 46, and a concentration chamber / cathode chamber 45 are disposed between the cathode 41 and the anode 42, respectively. The distance between 41 and the anode 42 is small. Therefore, even if the applied voltage between the electrodes 41 and 42 is low, a sufficient current can be passed between the electrodes 41 and 42 to perform the deionization process.

  In addition, since the electrode chamber also serves as the concentration chamber, the electrical conductivity of the electrode water is high. This also allows a sufficient current to flow between the electrodes 41 and 42 even if the applied voltage between the electrodes 41 and 42 is low.

  In this electric deionization apparatus, the outer shell is constituted by a pair of half shells 50 and 50A, and an end plate is unnecessary and the structure is simple. In addition, the water-tightness (watertightness) of seams and seams is also good. In addition, the outer shell of the electric deionizer is solid and has excellent durability and impact resistance.

  Since the half shells 50 and 50A and the frame 90 are made of heat-resistant synthetic resin, the electric deionization device can be disposed at a relatively high temperature (for example, next to the fuel cell).

The direction of water flow in the electrode / concentration chambers 45 and 46 may be the desalting chamber and the parallel circulating water or the counter-flowing water shown in the figure, but in any case, it is preferably the rising circulating water. This is because gas such as H ₂ , O ₂ , and Cl ₂ is generated in each electrode chamber / concentration chamber 45, 46 by a direct current, so that water flows in an upward flow to promote gas discharge and prevent drift. It is.

  In particular, in this embodiment, putty-like sealing material 49 is applied to the crossing corners between the longitudinal side wall surfaces of the recesses 61 and 61A and both side edges of the electrode plates 41 and 42 in the electrode chamber / concentration chambers 45 and 46. Since it is worn and chamfered, drift in this portion is prevented.

  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 the raw water and independently pass the water to each concentrating chamber / electrode chamber. According to this water flow method, since the effluent from one electrode chamber is conventionally used as the other electrode water, the ion species that have moved from the desalting chamber to each concentration chamber / electrode chamber do not associate. , Scale is less likely to occur.

  However, a portion of the demineralized water taken out from the electric deionizer is separated and distributed as an anode electrode water to the concentration chamber / anode chamber, and this concentrated water / anode electrode water discharge water is used as the cathode electrode water. You may distribute | circulate to a concentration chamber and a cathode chamber.

  Although the above embodiment has a three-chamber structure, the present invention is also applicable to the four-chamber structure shown in FIG.

  In the electric deionization apparatus shown in FIG. 11, a first cation exchange membrane 103, an anion exchange membrane 104, and a second cation exchange membrane 103 ′ are placed between a cathode 101 and an anode 102. A concentrating chamber / cathode chamber 105 is formed between the cathode 101 and the first cation exchange membrane 103, and a desalting chamber 107 is formed between the first cation exchange membrane 103 and the anion exchange membrane 104. The concentration chamber 110 is formed between the anion exchange membrane 104 and the second cation exchange membrane 103 ′, and the anode chamber 106 is formed between the second cation exchange membrane 103 ′ and the anode 102. .

  Although not shown in the figure, the cathode 101 and the anode 102 are held by a heat-resistant synthetic resin plate as in FIG. 10, and the desalination chamber 107 and the concentration chamber 110 are surrounded by a heat-resistant synthetic resin frame. ing.

  The concentration chamber / cathode chamber 105, the concentration chamber 110, and the anode chamber 106 are each filled with a cation exchange resin 108. The ion exchange resin filled in the concentration chamber / cathode chamber 105, the concentration chamber 110, and the anode chamber 106 may be an anion exchange resin or a mixture of an anion exchange resin and a cation exchange resin. From the viewpoint, it is preferable to use a cation exchange resin. The desalting chamber 107 is filled with a cation exchange resin 108 and an anion exchange resin 109 in a mixed state.

  An inlet of raw water is provided at one end of the desalting chamber 107, and an outlet of deionized water is provided at the other end.

  An inlet of raw water or deionized water is provided on one end side of the anode chamber 106. Outflow water from the anode chamber 106 flows into the concentrating chamber 110 from one end side and flows out from the other end side. The outflow water from the concentration chamber 110 flows into the concentration chamber / cathode chamber 105 from one end side and is discharged from the other end side as concentrated water / cathode electrode water.

  In a state where a voltage is applied between the cathode 101 and the anode 102, raw water is introduced into the demineralization chamber 107 and taken out as deionized water. As described above, raw water or the deionized water is introduced into the anode chamber 106 and sequentially passed through the concentration chamber 110 and the concentration chamber / cathode chamber 105. The cations in the raw water pass through the first cation exchange membrane 103 and are mixed with the cathode electrode water and discharged. The anions in the raw water permeate the anion exchange membrane 104 and move to the concentration chamber 110, enter the concentration chamber effluent, and are discharged through the concentration chamber / cathode chamber 105.

  Even in this electric deionization apparatus, only one concentration chamber / cathode chamber 105, demineralization chamber 107, concentration chamber 110, and anode chamber 106 are arranged between the cathode 101 and the anode 102, respectively. The distance between the cathode 101 and the anode 102 is small. Therefore, even if the applied voltage between the electrodes 101 and 102 is low, a sufficient current can be passed between the electrodes 101 and 102 to perform the deionization process.

In the present invention, Cl ⁻ in the desalting chamber moves only to the concentration chamber 110 and does not move to the anode chamber 106. For this reason, the Cl ⁻ concentration in the anode chamber 106 is only Cl ⁻ existing in the raw water or deionized water, and Cl ₂ generated by anodic oxidation in the anode chamber 106 is remarkably small. Therefore, deterioration of the cation exchange resin 108 in the anode chamber 106 and the second cation exchange membrane 103 ′ facing the anode chamber 106 is prevented.

  Since the cathode chamber also serves as the concentration chamber, the electrical conductivity of the electrode water in the cathode chamber is high. This also allows a sufficient current to flow between the electrodes 101 and 102 even if the applied voltage between the electrodes 101 and 102 is low.

The direction of water flow in the concentrating chamber / cathode chamber 105 and the concentrating chamber 110 may be the desalting chamber 107 and parallel flow water or counter flow water. It is desirable that the concentration / cathode chamber 105 and the anode chamber 106 are ascending circulation water. This is because gas such as H ₂ and O ₂ , and in some cases a small amount of Cl ₂ , is generated in each of the chambers 105 and 106 by a direct current. Because.

An example of the Cl load amount in the anode chamber when the concentration chamber 110 is omitted from the electric deionization apparatus of FIG. 11 and all Cl ⁻ flows into the anode chamber 106 from the desalting chamber 107 is calculated next. To do. The anode chamber is supplied with raw water having a Cl concentration of 3 ppm at 0.8 L / h, and the raw water is supplied to the desalting chamber at 1.5 L / h.

In this case, since substantially the entire amount of Cl moves from the desalting chamber to the anode chamber, the amount of Cl loading in the anode chamber is the amount of Cl from the desalting chamber = 1.5 L / h · 3 mg / L = 4.5 mg / H
Anode chamber inflow Cl amount = 0.8 L / h · 3 mg / L = 2.4 mg / h
The sum is 6.9 mg / h.

  On the other hand, in the case of FIG. 11, the amount of loading of the anode chamber Cl is only 2.4 mg / h because it is only Cl in the raw water flowing into the anode chamber. If deionized water is passed through the anode chamber, the anode chamber CI load is substantially zero.

As is apparent from this example, by disposing the concentration chamber between the desalting chamber and the anode chamber, the Cl concentration in the anode chamber can be lowered, and the amount of Cl ₂ generated in the anode chamber can be reduced.

It is a disassembled perspective view of the electric deionization apparatus which concerns on embodiment. It is an expansion disassembled perspective view of a part of electric deionization apparatus. It is an expansion disassembled perspective view of a part of electric deionization apparatus. It is a block diagram of a half shell. It is a block diagram of a half shell. It is sectional drawing of the longitudinal direction of an electrical deionization apparatus. It is sectional drawing which follows the VII-VII line of FIG. It is sectional drawing which follows the VIII-VIII line of FIG. It is sectional drawing which follows the IX-IX line of FIG. It is a schematic longitudinal cross-sectional view of the electric deionization apparatus which concerns on embodiment. It is a schematic longitudinal cross-sectional view which shows the electric deionization apparatus of 4 chamber structure.

Explanation of symbols

1,41 Cathode 2,42 Anode 3,43 Cation exchange membrane 4,44 Anion exchange membrane 5,45 Concentration chamber / cathode chamber 6,46 Concentration chamber / anode chamber 7,47 Desalination chamber 10,20 Plate 11,21 Recess 30 frame 34 inlet 35 outlet 50, 50A half shell 90 frame

Claims (9)

A cation exchange membrane and an anion exchange membrane are disposed between the cathode and the anode held on each plate,
Between the cation exchange membrane arranged on the cathode side and the anion exchange membrane arranged on the anode side, a desalting chamber surrounded by a frame is provided,
In the electric deionization apparatus in which an inflow path and an outflow path for electrode water are provided in each plate,
The plate and frame are made of heat-resistant synthetic resin,
The inflow path and the outflow path are connected to the cathode chamber and the anode chamber, respectively, around the edge of the electrode plate constituting the cathode and the anode.   2. The electric deionization device according to claim 1, wherein each of the inflow passage and the outflow passage extends in a direction away from the back surface of the electrode plate and faces the outer surface of the electric deionization device. In Claim 1 or 2, a cation exchange membrane and an anion exchange membrane are arranged one by one,
The space between the cathode and the cation exchange membrane is a concentration chamber / cathode chamber,
An electric deionization apparatus characterized in that a space between the anode and the anion exchange membrane serves as a concentration chamber / anode chamber. In Claim 1 or 2, the first cation exchange membrane, the anion exchange membrane, and the second cation exchange membrane are arranged in this order,
A space between the cathode and the first cation exchange membrane is a concentration chamber / cathode chamber,
A space between the first cation exchange membrane and the anion exchange membrane is a desalting chamber,
A concentration chamber is formed between the anion exchange membrane and the second cation exchange membrane,
An electric deionization apparatus characterized in that an anode chamber is provided between the second cation exchange membrane and the anode. One cation exchange membrane and one anion exchange membrane are disposed between the cathode and the anode,
A concentration chamber / cathode chamber is provided between the cathode and the cation exchange membrane,
A concentration and anode chamber is provided between the anode and the anion exchange membrane,
An electric deionization apparatus in which a demineralization chamber is provided between the cation exchange membrane and the anion exchange membrane,
The outer shell of the electric deionization apparatus is composed of a pair of half shells on the cathode side and the anode side that are overlapped facing each other,
These half shells are made of heat-resistant synthetic resin,
Each half shell has a concavity on the opposite side,
The inside of the recess of the cathode-side half shell is the concentration chamber / cathode chamber separated from the desalting chamber by the cation exchange membrane,
The concentrating chamber / anode chamber separated from the desalting chamber by the anion exchange membrane in the recess of the anode-side half shell,
An electric deionization apparatus comprising a frame made of a heat-resistant synthetic resin and surrounding the demineralization chamber between the cation exchange membrane and the anion exchange membrane. A first cation exchange membrane, an anion exchange membrane, and a second cation exchange membrane are arranged in this order between the cathode and the anode,
A concentration chamber / cathode chamber is provided between the cathode and the first cation exchange membrane;
A desalting chamber is provided between the first cation exchange membrane and the anion exchange membrane;
A concentration chamber is provided between the anion exchange membrane and the second cation exchange membrane;
An electrical deionization apparatus in which an anode chamber is provided between the second cation exchange membrane and the anode,
The outer shell of the electric deionization apparatus is composed of a pair of half shells on the cathode side and the anode side that are overlapped facing each other,
These half shells are made of heat-resistant synthetic resin,
Each half shell has a concavity on the opposite side,
The inside of the recess of the cathode-side half shell is the concentration chamber / cathode chamber separated from the desalting chamber by the first cation exchange membrane,
The inside of the recess of the anode-side half shell is the anode chamber separated from the concentration chamber by the second cation exchange membrane;
Between the first cation exchange membrane and the anion exchange membrane, a frame made of a heat-resistant synthetic resin and surrounding the periphery of the desalting chamber is interposed,
An electric deionization apparatus characterized in that a frame made of a heat-resistant synthetic resin and surrounding the concentration chamber is interposed between the anion exchange membrane and the second cation exchange membrane. In claim 5 or 6, an electrode plate is disposed at the bottom of each recess,
An electric deionizing apparatus, wherein each half shell is provided with an inflow path and an outflow path for allowing concentrated water / electrode water to flow through the concentration room / cathode room and the concentration room / anode room, respectively.   8. The inflow path and the outflow path according to claim 7, each of which extends around an edge of the electrode plate, extends in a direction away from the back surface of the electrode plate, and faces the outer surface of each half shell. An electrical deionization device characterized by the above.   9. The electric deionization device according to claim 1, wherein the heat-resistant synthetic resin is syndiotactic polystyrene or polyacetal resin.

Images