JP6873735B2 - Electric deionized water production equipment and water treatment equipment and water treatment method using this - Google Patents

Description

The present invention relates to an electric deionized water production apparatus, a water treatment apparatus using the same, and a water treatment method, and more particularly to filling an anion exchanger and a cation exchanger into a desalting chamber.

Conventionally, an electric deionized water production device (hereinafter, also referred to as EDI) that does not require regeneration of an ion exchanger by a chemical agent has been developed and put into practical use. The EDI has a cathode chamber and an anode chamber facing each other, a desalting chamber located between the cathode chamber and the anode chamber, and a pair of concentrating chambers adjacent to the desalting chamber. The desalting chamber is partitioned by an anion exchange membrane on the anode chamber side and by a cation exchange membrane on the cathode chamber side. Patent Document 1 discloses a mixed bed type EDI in which a desalting chamber is divided into an anion exchanger filled portion filled with an anion exchanger and a cation exchanger filled portion filled with a cation exchanger. ing. The water to be treated becomes deionized water by removing the anion component and the cation component at the anion exchanger-filled portion and the cation exchanger-filled portion.

Japanese Patent No. 5719842

Depending on the use of deionized water, it may be desired to preferentially remove the cationic component over the anionic component. In such a case, it is common to change the volume ratio (resin filling ratio) of the anion exchanger-filled portion and the cation exchanger-filled portion. For example, in an EDI in which the volume ratio of the anion exchanger-filled portion and the cation exchanger-filled portion is 5: 5, the cation component can be removed more efficiently by changing the ratio to 4: 6. However, in this case, the efficiency of removing the anion component decreases.

Therefore, an object of the present invention is to provide an electric deionized water production apparatus capable of increasing the removal efficiency of the cation component without lowering the removal efficiency of the anion component.

The electric deionized water production apparatus of the present invention is located between the anode chamber and the cathode chamber facing each other and the anode chamber and the cathode chamber, and has an anion exchange membrane on the anode chamber side and a cation exchange membrane on the cathode chamber side. It has a desalting chamber in which water to be treated flows, and a pair of concentrating chambers adjacent to each of the desalting chambers via an anion exchange membrane and a cathode exchange membrane. In the desalting chamber, at least one anion exchanger-filled portion filled with an anion exchanger and at least one cation exchanger-filled portion filled with a cation exchanger are provided along the flow path of the water to be treated. They are arranged alternately. The anion exchange membrane and the cation exchange membrane have flexibility. The total volume of the anion exchanger filling part is Va, the total volume of the cation exchanger filling part is Vk, the volume of the anion exchanger filling part when the desalting chamber is not filled with the anion exchanger and the cation exchanger is Va0, When the desalting chamber is not filled with the anion exchanger and the cation exchanger, the volume of the cation exchanger filling portion is Vk0, the anion exchanger filling rate Ra is Va / Va0, and the cation exchanger filling rate Rk is Vk / Vk0. When this is done, Rk ≧ 1.20 and 1.05 ≧ Ra ≧ 1.

According to the present invention, since the cation exchanger packing factor Rk is larger than the anion exchanger filling factor Ra (Rk> Ra), the efficiency of removing the cation component can be improved. Further, the volume of the anion exchanger filled in the anion exchanger filling portion is the same as or larger than the volume of the anion exchanger filling portion when the desalting chamber is not filled with the anion exchanger and the cation exchanger. (Ra ≧ 1). Therefore, the decrease in the removal efficiency of the anion component is suppressed. Therefore, according to the present invention, it is possible to provide an electric deionized water production apparatus capable of increasing the removal efficiency of the cation component without lowering the removal efficiency of the anion component.

It is a schematic block diagram of EDI which concerns on 1st Embodiment of this invention. It is an enlarged perspective view of the desalting chamber shown in FIG. It is a schematic block diagram of EDI which concerns on 2nd Embodiment of this invention. It is a schematic block diagram of EDI which concerns on 3rd Embodiment of this invention. It is an enlarged perspective view of the desalting chamber shown in FIG. It is a schematic block diagram of EDI which concerns on 4th Embodiment of this invention. It is a schematic block diagram of EDI which concerns on 5th Embodiment of this invention. It is a graph which shows the relationship between the temperature of the water to be treated, the specific resistance of the treated water, and the Na ion concentration.

(First Embodiment)
Hereinafter, the first embodiment of EDI of the present invention will be described with reference to the drawings.

FIG. 1 is a schematic configuration diagram of EDI4 according to the first embodiment of the present invention. The EDI4 is located between the anode chamber E1 and the cathode chamber E2 facing each other and the anode chamber E1 and the cathode chamber E2, and is the first anion exchange film a1 on the anode chamber E1 side and the first on the cathode chamber E2 side. A desalting chamber D partitioned by a cation exchange membrane k1 and filled with an anion exchanger and a cation exchanger, and a desalting chamber D via a first cation exchange membrane k1 and a first anion exchange membrane a1 respectively. It has a pair of concentrating chambers C1 and C2 that are adjacent to each other. Hereinafter, the concentration chamber on the anode chamber E1 side adjacent to the desalting chamber D via the first anion exchange membrane a1 is referred to as the first concentration chamber C1, and the desalting chamber D is referred to via the first cation exchange membrane k1. The concentration chamber on the cathode chamber E2 side adjacent to the second concentration chamber C2 is referred to as a second concentration chamber C2. The anode chamber E1 and the first concentration chamber C1 are separated by a second cation exchange membrane k2, and the cathode chamber E2 and the second concentration chamber C2 are separated by a second anion exchange membrane a2. Electrode water flows through the anode chamber E1 and the cathode chamber E2, concentrated water flows through the first and second concentration chambers C1 and C2, and water to be treated flows through the desalination chamber D. These waters flow vertically inside the EDI4. There is no limit to the number of desalting chambers, and two or more desalting chambers can be provided. In this case, the concentration chamber and the desalination chamber are alternately arranged between the anode chamber E1 and the cathode chamber E2, and a plurality of desalination chambers are arranged in parallel or in series.

The anode chamber E1 houses an anode (not shown), and the cathode chamber E2 houses a cathode (not shown). The anode and cathode are made of a metal mesh or plate such as stainless steel. The electrode water supplied to the anode chamber E1 and the cathode chamber E2 generates hydroxide ions and hydrogen ions by electrolysis in the vicinity of the electrodes, respectively. In order to suppress the electrical resistance of the EDI4, it is preferable that the anode chamber E1 and the cathode chamber E2 are filled with an ion exchanger.

The concentrated water flowing through the first and second concentration chambers C1 and C2 is supplied from the concentrated water supply pipe L3. The ionic components removed in the desalting chamber D move to the first and second concentration chambers C1 and C2, and are discharged from the concentrated water drain pipe L4 to the outside of the EDI4 together with the concentrated water. In order to suppress the electrical resistance of EDI4, it is preferable that the first and second concentration chambers C1 and C2 are filled with an ion exchanger. However, in the present embodiment, as will be described later, the desalting chamber D is filled with more cation exchanges than before, and as a result, the first cation exchange membrane k1 and the first anion exchange membrane a1 are out of plane. Overhang. The amount of ion exchangers filled in the first and second concentration chambers C1 and C2 is such that the first cation exchange membrane k1 and the first anion exchange membrane a1 project out of the plane, and a sufficient amount of cation exchangers are used. It is preferable to adjust so that the mixture can be filled.

The water to be treated flows into the desalting chamber D through the water supply pipe L1 to be treated, the ionic components (anionic component and cation component) are removed in the desalting chamber D, and the treated water is discharged as deionized water (treated water). It is discharged to the pipe L2. ^{The anion components (Cl −} , CO ₃ ^2- , HCO ₃ ⁻ , SiO ₂ etc.) removed from the water to be treated move to the first concentration chamber C1 through the first anion exchange membrane a1 and move to the water to be treated. The cation components (Na ⁺ , Ca ²⁺ , Mg ^2+, etc.) removed from the cation exchange membrane move to the second concentration chamber C2 through the first cation exchange membrane k1.

The desalting chamber D is divided into an anion exchanger filled portion A filled with an anion exchanger and a cation exchanger filled portion K filled with a cation exchanger. That is, in the desalination chamber, at least one anion exchanger-filled portion A filled with the anion exchanger and at least one cation exchanger-filled portion K filled with the cation exchanger are connected to the flow path of the treated water. They are arranged alternately along. The anion exchanger and the cation exchanger are composed of a granular anion exchange resin and a cation exchange resin, respectively, but other ion exchangers such as an ion exchange fiber and a monolithic organic porous ion exchanger as long as they exhibit an ion exchange action. Can also be used. The number of the anion exchanger filling portion A and the cation exchanger filling portion K is not limited, but at least one anion exchanger filling portion A and at least one cation exchanger filling portion K are vertically arranged in the desalting chamber D. It suffices if they are arranged in a row and alternately. In the present embodiment, the first anion exchanger filling portion A1, the first cation exchanger filling portion K1, and the second anion exchanger filling portion A2 are provided in this order, and the water to be treated is the first. Passes through the anion exchanger filling portion A1, the first cation exchanger filling portion K1, and the second anion exchanger filling portion A2 in this order. Although not shown, another cation exchanger filling portion may be provided on the upstream side of the first anion exchanger filling portion A1 (the water to be treated is a cation exchanger, an anion exchanger, cation exchanger, anion exchange). It flows in the order of the body). There is no physical barrier between the anion exchanger filling portions A1 and A2 and the cation exchanger filling portion K, and these filling portions are formed by individually filling the anion exchanger and the cation exchanger (respectively). So-called double-bed form).

Since the anion exchange membrane and the cation exchange membrane are thin membranes, they have flexibility in the out-of-plane direction, that is, on the anode side and the cathode side. In the present embodiment, the filling amount of the cation exchange is increased, and as a result, the first anion exchange membrane a1 and the first cation exchange membrane k1 project in the out-of-plane direction, that is, toward the adjacent concentration chambers C1 and C2. Specifically, the first anion exchange membrane a1 overhangs the first concentration chamber C1 side, and the first cation exchange membrane k1 overhangs the second concentration chamber C2 side.

Here, the packing rates of the anion exchanger and the cation exchanger are defined as follows. FIG. 2 is a schematic perspective view of the desalination chamber D, FIG. 2 (a) is when the anion exchanger and the cation exchanger are not filled, and FIG. 2 (b) is filled with the anion exchanger and the cation exchanger. The desalting chamber D, the first anion exchange membrane a1 and the first cation exchange membrane k1 are shown. As shown in FIG. 2A, when the anion exchanger and the cation exchanger are not filled, the first anion exchange film a1 and the first cation exchange film k1 are not deformed in the out-of-plane direction. , It is in a plane substantially orthogonal to the straight line connecting the center of the anode chamber E1 and the center of the cathode chamber E2. As shown in FIG. 2B, when the anion exchange body and the cation exchange body are filled, the first anion exchange membrane a1 and the first cation exchange membrane k1 project in the out-of-plane direction.

In FIG. 2B, the reference numerals are defined as follows.
Va: Total volume of anion exchanger filling part A Va1: Volume of first anion exchanger filling part A1 Va2: Volume of second anion exchanger filling part A2 Vk: Total volume of cation exchanger filling part K Vk1: Volume of the first cation exchanger filling portion K1 Ha: Total filling height of the anion exchanger Hk: Total filling height of the cation exchanger W: The desalting chamber D is not filled with the anion exchanger and the cation exchanger. Distance between the first anion exchange film a1 and the first cation exchange film k1 S Depth of the desalting chamber D The total volume is the total volume when there are a plurality of anion exchanger filling portions or a plurality of cation exchanger filling portions. It means the total volume of a plurality of anion exchanger filling parts or the total volume of a plurality of cation exchanger filling parts. Therefore, in the case of FIG. 2B, Va = Va1 + Va2 and Vk = Vk1. The total filling height is the sum of the heights of the plurality of anion exchanger filling portions or the height of the plurality of cation exchanger filling portions when there are a plurality of anion exchanger filling portions or a plurality of cation exchanger filling portions. Means the sum of. Therefore, in the case of FIG. 2B, Ha = Ha1 + Ha2 and Hk = Hk1. The height is defined in the direction parallel to the flow direction of the water to be treated.

In FIG. 2A, the volume of the anion exchanger filling portion A is Va0, and the volume of the cation exchanger filling portion K is Vk0. Va0 is the volume of the anion exchanger filling portion A in FIG. 2B when the anion exchanger and the cation exchanger are not filled, and Vk0 is the cation exchanger filling portion K in FIG. 2B. This is the volume when the anion exchanger and the cation exchanger are not filled. The volume of the first anion exchanger filling portion A1 when the anion exchanger is not filled is Va01, the volume of the second anion exchanger filling portion A2 when the anion exchanger is not filled is Va02, and the first Assuming that the volume of the cation exchanger-filled portion K1 when the anion exchanger is not filled is Vk01, Va0 = Va01 + Va02 and Vk = Vk01. Since the total filling height Ha of the anion exchanger and the total filling height Hk of the cation exchanger are the same in FIGS. 2A and 2B, Va0 = Ha × S × W and Vk0 = Hk × S × It becomes W. The depth S of the desalting chamber D is defined in a direction orthogonal to both the straight line connecting the center of the anode chamber E1 and the center of the cathode chamber E2 and the direction in which the water to be treated flows, and is filled with an anion exchanger and a cation exchanger. It is constant regardless of whether it is done or not.

From the above, the anion exchanger filling factor Ra and the cation exchanger packing factor Rk are defined as follows.
Anion exchanger filling factor Ra = Va / Va0 = Va / (Ha × S × W)
Cation exchanger filling factor Rk = Vk / Vk0 = Vk / (Hk × S × W)
In the present embodiment, Vk> Vk0 and Va> Va0, but Va = Va0 may be used for Va.

Further, in this embodiment, Rk> Ra holds. Since Va ≧ Va 0, Rk> Ra ≧ 1 is established after all. By filling the cation exchanger and the anion exchanger in this way, the cation component can be removed more efficiently. Since a constant filling amount is secured for the anion exchanger as well, the ability to remove the anion component does not decrease. Further, both Rk and Ra are preferably 1 or more, whereby the adhesion between the ion exchanger and the ion exchange membrane is ensured, and the ions can be efficiently transferred to the concentration chamber. As is clear from the above definition, Rk> Ra does not mean that the filling amount of the cation exchanger is larger than the filling amount of the anion exchanger (Vk> Va). In other words, Rk> Ra means that the average value of the widthwise dimensions of the cation exchanger filling portion K is larger than the average value of the widthwise dimensions of the anion exchanger filling portion A.

On the upstream side of the EDI4, a reverse osmosis membrane (RO) device 2 for removing impurities such as salts from the water to be treated and a heating means 3 for heating the RO permeated water are provided. The heating means 3 is not particularly limited, and may be a heater, a heat exchanger, or the like. The heating means 3 is used, for example, for hot water sterilization of water to be treated. The RO device 2 and the heating means 3 together with the EDI4 form a part of the water treatment device 1. As will be described later, according to the present invention, even if the water to be treated is heated to 40 ° C. or higher, the decrease in the efficiency of removing the cation component can be suppressed. Therefore, the water treatment method of the present invention includes a step of heating the water to be treated to 40 ° C. or higher and a step of supplying the water to be treated heated to 40 ° C. or higher to EDI4 and treating the water to be treated with EDI4. , Have.

(Second Embodiment)
FIG. 3 is a schematic configuration diagram of EDI4 according to the second embodiment of the present invention. The second embodiment is the same as the first embodiment except that the anion exchanger filling portion A is provided with the first bipolar film BP1 and the cation exchanger filling portion K is provided with the second bipolar film BP2. Is. Specifically, the first bipolar film BP1 is provided on the cathode side of the anion exchanger-filled portion A, and the second bipolar film BP2 is provided on the anode side of the cation exchanger-filled portion K. The first and second bipolar membranes BP1 and BP2 are formed by laminating the anion exchange membrane BPa and the cation exchange membrane BPk. The anion exchange membrane BPa of the first bipolar membrane BP1 is in contact with the anion exchanger, and the cation exchange membrane BPk of the second bipolar membrane BP2 is in contact with the cation exchanger. The bipolar film has the effect of promoting the water splitting reaction and making it easier for the current to flow. By providing the first and second bipolar films BP1 and BP2, the efficiency of removing the anion component and the cation component is enhanced.

(Third Embodiment)
FIG. 4 is a schematic configuration diagram of EDI4 according to a third embodiment of the present invention. FIG. 5 is a schematic perspective view of the desalination chamber D, FIG. 5 (a) is when the anion exchanger and the cation exchanger are not filled, and FIG. 5 (b) is filled with the anion exchanger and the cation exchanger. The desalting chamber D, the anion exchange membrane, and the cation exchange membrane are shown. The third embodiment is the same as the first embodiment except that the desalting chamber D is divided into two small desalting chambers D1 and D2. Specifically, the desalting chamber D contains an intermediate ion exchange membrane x located between the first anion exchange membrane a1 and the first cation exchange membrane k1, and the first anion exchange membrane a1 and intermediate ion exchange. It has a first small desalting chamber D1 partitioned by the membrane x and a second small desalting chamber D2 partitioned by the first cation exchange membrane k1 and the intermediate ion exchange membrane x. .. The intermediate ion exchange membrane x may be either a single membrane of an anion exchange membrane or a cation exchange membrane, or a composite membrane having both an anion exchange membrane and a cation exchange membrane. The first small desalting chamber D1 and the second small desalting chamber D2 are connected in series by the connection flow path L5, and the water to be treated is from the first small desalting chamber D1 to the second small desalting chamber D2. Flow to.

The configuration in which the desalination chamber D is divided into two small desalination chambers in this way enables multi-stage treatment of the water to be treated, and is effective in improving the deionization performance. Moreover, since it is not necessary to provide a concentration chamber between the first small desalination chamber D1 and the second small desalination chamber D2, the applied voltage between the anode and the cathode is suppressed, the power consumption is reduced, and the operating cost is reduced. It is possible to reduce the amount.

In the desalting chamber D, at least one anion exchanger filling portion A and at least one cation exchanger filling portion K are alternately arranged along the flow path of the water to be treated. In the present embodiment, the first small desalination chamber D1 is filled with an anion exchanger, the second small desalination chamber D2 is filled with a cation exchanger on the upstream side and an anion on the downstream side in the flow direction of the water to be treated. The replacement body is filled. Therefore, the water to be treated passes in the order of the first anion exchanger filling portion A1, the second cation exchanger filling portion K2, and the second anion exchanger filling portion A2. The upstream side of the first small desalination chamber D1 is filled with an anion exchanger, the downstream side is filled with a cation exchanger, the second small desalination chamber D2 is filled with an anion exchanger, and the first small desalting chamber is demineralized. It is also possible to allow the water to be treated to flow from the chamber D1 to the second small desalination chamber D2.

In the present embodiment, Rk> Ra ≧ 1 is established for each small desalination chamber in which at least one anion exchanger filling portion A and at least one cation exchanger filling portion K are arranged. That is, in the present embodiment, the first small desalting chamber D1 is filled with only the anion exchanger, and the second small desalting chamber D2 is filled with the cation exchanger and the anion exchanger. Rk> Ra ≧ 1 holds in the small desalination chamber D2. In FIG. 5B, the reference numerals are defined as follows.
Va1: Volume of the first anion exchanger filling part A1 Va2: Volume of the second anion exchanger filling part A2 Vk1: Volume of the first cation exchanger filling part K1 (Vk1 = 0 in this embodiment)
Vk2: Volume of the second cation exchanger filling portion K2 Ha1: Total filling height of the anion exchanger filled in the first small desalting chamber D1 Hk1: Cation filled in the first small desalting chamber D1 Total filling height of the exchanger (Hk1 = 0 in this embodiment)
Ha2: Total filling height of the anion exchange membrane filled in the second small desalting chamber D2 Hk2: Total filling height of the cation exchange membrane filled in the second small desalting chamber D2 W1: Desalting chamber D Distance between the first anion exchange membrane a1 and the intermediate ion exchange membrane x when the anion exchanger and the cation exchange membrane are not filled in W2: The desalting chamber D is not filled with the anion exchanger and the cation exchange membrane. Distance between intermediate ion exchange membrane x and first cation exchange membrane k1 S: Depth of desalting chamber D Here, considering the second small desalting chamber D2,
Va0 = Ha2 × S × W2
Vk0 = Hk2 × S × W2
And
Anion exchanger filling factor Ra = Va2 / (Ha2 × S × W2)
The cation exchanger packing factor Rk = Vk2 / (Hk2 × S × W2).

The same applies when the first small desalting chamber D1 is filled with a cation exchanger and an anion exchanger. When the first small desalting chamber D1 and the second small desalting chamber D2 are filled with a cation exchanger and an anion exchanger, respectively, the first small desalting chamber D1 and the second small desalting chamber D1 and the second small desalting chamber D1 are filled. Rk> Ra ≧ 1 holds for each of the chambers D2.

(Fourth Embodiment)
FIG. 6 is a schematic configuration diagram of EDI4 according to a fourth embodiment of the present invention. The fourth embodiment is the same as the third embodiment except that the first bipolar film BP1 is provided in the anion exchanger filling portion A. Specifically, the first bipolar membrane BP1 is provided on the cathode side of the anion exchanger filling portion A, and the anion exchange membrane BPa of the first bipolar membrane BP1 is in contact with the anion exchanger. In general, anion exchangers have higher electrical resistance than cation exchangers, and it is difficult for current to flow. Therefore, the current easily flows through the cation exchanger, and the efficiency of removing the anion component may decrease due to the influence of this drift. Since the bipolar membrane promotes the dissociation reaction of water at the junction surface between the anion exchange membrane and the cation exchange membrane, it has an effect of making it easier for an electric current to flow. Therefore, the drift is improved by providing the first bipolar film BP1 in the anion exchanger filling portion A.

(Fifth Embodiment)
FIG. 7 is a schematic configuration diagram of EDI4 according to a fourth embodiment of the present invention. The fifth embodiment is the same as the fourth embodiment except that the cation exchanger filling portion K is provided with the second bipolar film BP2. Specifically, a second bipolar membrane BP2 is provided on the anode side of the cation exchanger filling portion K, and the cation exchange membrane BPk of the second bipolar membrane BP2 is in contact with the cation exchanger. The fourth embodiment improves the drift, but reduces the current flowing through the cation exchanger packing section K. Therefore, the second bipolar film BP2 can be provided on the cation exchanger-filled portion K to increase the current flowing through the cation exchanger-filled portion K.

(Example)
Next, some examples will be described. In each Example and each Comparative Example, water treated with a one-stage reverse osmosis membrane (RO membrane) was supplied to EDI. The examples and comparative examples corresponding to the configurations of the desalting chambers shown in the left column of Table 1 differ only in the anion exchanger filling factor Ra and the cation exchanger filling factor Rk. The larger the resistivity of the treated water, the more the ionic component is removed, and the amount of Na ions indicates the concentration of Na ions, which is a typical example of cation ions, in the treated water.

In Example 1, the EDI shown in FIG. 6 has an anion exchanger filling factor Ra = 1.05 and a cation exchanger filling factor Rk = 1.20. In Comparative Example 1, in the EDI shown in FIG. 6, the anion exchanger filling factor Ra = 1.10 and the cation exchanger filling factor Rk = 1.10. In Example 1, the specific resistance of the treated water is larger than that of Comparative Example 1, the amount of Na ions in the treated water is also reduced, and the cation component is efficiently removed.

In Example 2, the EDI shown in FIG. 7 has an anion exchanger filling factor Ra = 1.05 and a cation exchanger filling factor Rk = 1.20. In Comparative Example 2, in the EDI shown in FIG. 7, the anion exchanger filling factor Ra = 1.10 and the cation exchanger filling factor Rk = 1.10. Also in Example 2, the specific resistance of the treated water is larger than that of Comparative Example 2, the amount of Na ions in the treated water is also reduced, and the cation component is efficiently removed.

Next, as Example 3, hot water sterilized water to be treated was introduced into EDI4, and the specific resistance and Na ion amount of the treated water were measured by changing the temperature of the hot water. Specifically, in EDI4 of Example 2 and Comparative Example 2, the specific resistance and the amount of Na ions of the treated water when the water to be treated was heated to 40 ° C. and 80 ° C. were measured. Hot water sterilization was performed 50 times in each case, and the average values of resistivity and Na ion amount were obtained in each case. The specific resistance and the amount of Na ions of the treated water when the water to be treated is not heated are as in Example 2 and Comparative Example 2. As shown in FIG. 8, when hot water sterilization is performed at 40 ° C., a slight difference is observed between the examples and the comparative examples, and when the temperature exceeds 40 ° C., the difference becomes large, and at 80 ° C., the difference becomes even larger. Therefore, from this example, it was found that the cation ion can be effectively removed when the water to be treated at 40 ° C. or higher is introduced into EDI4.

1 Water treatment equipment 2 RO equipment 3 Heating means 4 Electric deionized water production equipment (EDI)
D Desalination chamber D1 First small desalination chamber D2 Second small desalination chamber C1 First concentration chamber C2 Second concentration chamber E1 Anode chamber E2 Cathode chamber a1 First anion exchange membrane a2 Second anion Exchange membrane k1 1st cation exchange membrane k2 2nd cation exchange membrane x intermediate ion exchange membrane

Claims (8)

Anode chamber and cathode chamber facing each other,
A desalting chamber located between the anode chamber and the cathode chamber, partitioned by an anion exchange membrane on the anode chamber side and a cation exchange membrane on the cathode chamber side, and through which water to be treated flows.
It has a pair of concentration chambers adjacent to the desalting chamber via the anion exchange membrane and the cation exchange membrane, respectively.
In the desalting chamber, at least one anion exchanger-filled portion filled with an anion exchanger and at least one cation exchanger-filled portion filled with a cation exchanger are provided in the flow path of the water to be treated. Alternately arranged along
The anion exchange membrane and the cation exchange membrane have flexibility and
The total volume of the anion exchanger filling part is Va,
The total volume of the cation exchanger packed portion is Vk,
When the desalting chamber is not filled with the anion exchanger and the cation exchanger, the volume of the anion exchanger-filled portion is Va0.
When the desalting chamber is not filled with the anion exchanger and the cation exchanger, the volume of the cation exchanger-filled portion is Vk0.
Anion exchanger filling factor Ra is Va / Va0,
When the cation exchanger packing factor Rk is Vk / Vk0,
An electric deionized water production apparatus in which Rk ≧ 1.20 and 1.05 ≧ Ra ≧ 1. The total filling height of the anion exchanger is Ha,
The total filling height of the cation exchanger is Hk,
The distance between the anion exchange membrane and the cation exchange membrane when the desalting chamber is not filled with the anion exchanger and the cation exchange membrane is W.
When the depth of the desalting chamber is S,
The anion exchanger filling factor Ra is Va / (Ha × S × W),
The electric deionized water production apparatus according to claim 1, wherein the cation exchanger filling factor Rk is Vk / (Hk × S × W). Anode chamber and cathode chamber facing each other,
A desalting chamber located between the anode chamber and the cathode chamber, partitioned by an anion exchange membrane on the anode chamber side and a cation exchange membrane on the cathode chamber side, and through which water to be treated flows.
It has a pair of concentration chambers adjacent to the desalting chamber via the anion exchange membrane and the cation exchange membrane, respectively.
The desalting chamber includes an intermediate ion exchange membrane located between the anion exchange membrane and the cation exchange membrane, and a first small desalting chamber partitioned by the anion exchange membrane and the intermediate ion exchange membrane. A second small desalting chamber partitioned by the cation exchange membrane and the intermediate ion exchange membrane and connected in series with the first small desalting chamber.
At least one of the first small desalting chamber and the second small desalting chamber is filled with at least one anion exchanger filled with an anion exchanger and at least one filled with a cation exchanger. and a cation exchanger filled portion along said flow path of the water to be treated are placed independently of one another,
The anion exchange membrane and the cation exchange membrane have flexibility and
A small desalting chamber in which the at least one anion exchanger filling portion and the at least one cation exchanger filling portion are arranged (however, the at least one anion exchanger filling portion and the at least one cation exchanger filling portion). If there are multiple small desalination chambers in which the filling part is arranged, in each small desalination chamber) ,
The total volume of the anion exchanger filling part is Va,
The total volume of the cation exchanger packed portion is Vk,
When the small desalting chamber is not filled with the anion exchanger and the cation exchanger, the volume of the anion exchanger-filled portion is Va0.
When the small desalting chamber is not filled with the anion exchanger and the cation exchanger, the volume of the cation exchanger-filled portion is Vk0.
Anion exchanger filling factor Ra is Va / Va0,
When the cation exchanger packing factor Rk is Vk / Vk0,
An electric deionized water production apparatus in which Rk ≧ 1.20 and 1.05 ≧ Ra ≧ 1. In the small desalting chamber in which the at least one anion exchanger filling portion and the at least one cation exchanger filling portion are arranged.
The total filling height of the anion exchanger is Ha,
The total filling height of the cation exchanger is Hk,
When the small desalting chamber is not filled with the anion exchanger and the cation exchanger, the distance between the anion exchange membrane and the cation exchange membrane is W.
When the depth of the small desalination chamber is S,
The anion exchanger filling factor Ra is Va / (Ha × S × W),
The electric deionized water production apparatus according to claim 3, wherein the cation exchanger filling factor Rk is Vk / (Hk × S × W). A first bipolar membrane in which an anion exchange membrane and a cation exchange membrane are bonded is provided on the cathode side of the anion exchange filling portion, and the anion exchange membrane of the first bipolar membrane is in contact with the anion exchange. The electric deionized water production apparatus according to any one of claims 1 to 4. A second bipolar membrane in which an anion exchange membrane and a cation exchange membrane are bonded is provided on the anode side of the cation exchanger filling portion, and the cation exchange membrane of the second bipolar membrane is in contact with the cation exchanger. The electric deionized water production apparatus according to claim 5. The electric deionized water production apparatus according to any one of claims 1 to 6.
A water treatment apparatus provided on the upstream side of the electric deionized water producing apparatus and having a heating means for heating the water to be treated supplied to the electric deionized water producing apparatus. A water treatment method using the electric deionized water producing apparatus according to any one of claims 1 to 6, wherein the water to be treated is heated to 80 ° C. or higher and heated to 80 ° C. or higher. A water treatment method comprising a step of supplying the treated water to be treated to the electric deionized water producing apparatus and treating the treated water with the electric deionized water producing apparatus.

Images