JPH09122643A - Method for treating waste water from ion exchange resin regeneration and its apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To decrease the amt. of use of chemicals such as an acid and an alkali for regeneration by a method wherein waste water generated by regeneration of an ion exchange resin is made to pass through a bipolar membrane apparatus provided with a cation exchange membrane, an anion exchange membrane and a bipolar membrane and the acid and the alkali obtd. are independently separated to use them again. SOLUTION: For regeneration of an ion exchange resin, at first, hydrochloric acid is fed into a cation exchange resin tower 3 from an acid storing tank 1 and sodium hydroxide is fed into an anion exchange resin tower 4 from an alkali storing tank 2 and all the regeneration waste water obtd. after passing through each tower 3 and 4 is fed into a neutralization tank 5. Here, hydrochloric acid or sodium hydroxide for neutralization is added to neutralize sodium hydroxide or hydrochloric acid which has not been consumed. Then, sodium chloride from the neutralization tank 5 is fed into a bipolar membrane apparatus 6 provided with a cation exchange membrane, an anion exchange membrane and a bipolar membrane, where it is separated into hydrochloric acid and sodium hydroxide and they are separately returned to the acid storing tank 1 and the alkali storing tank 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for treating ion-exchange resin recycled wastewater, and more specifically, to the field of using pure water as a solvent for boiler water and chemical products in power plants, or cleaning in semiconductor manufacturing. In the field of using ultrapure water, etc., it relates to a technology for treating recycled wastewater generated when the ion exchange resin is recycled.

[0002]

2. Description of the Related Art Generally, ion exchange resins are used for various purposes, and an example of such uses is a pure water production apparatus as shown in FIG.

That is, this apparatus comprises a cation exchange resin tower 3a, a decarbonation tower 16a, and an anion exchange resin tower 4a, as shown in the figure, and the raw water is first passed through the cation exchange resin tower 3a to obtain a cation exchange resin tower 3a. By adsorbing the ionic component, the cation component is removed from the raw water, then the carbon dioxide gas is removed by the decarbonation tower 16a, and then the anion exchange resin tower 4a is passed to adsorb the anion component. The pure water is produced by removing the anion components.

However, when used for a certain period of time, a certain amount of the cation component and the anion component are adsorbed by the ion exchange resin in the exchange resin tower, so that the adsorption ability of the ion exchange resin is lost.

Therefore, it is necessary to regenerate the ion exchange resin by desorbing the adsorbed cation components and anion components from the ion exchange resin.

As this regenerating work, conventionally, as shown in FIG. 8, an acid storage tank 1a storing hydrochloric acid is connected to a cation exchange resin tower 3a and an alkali storage storing caustic soda is stored in an anion exchange resin tower 4a. A system in which the tank 2a is connected is adopted.

In this system, first, hydrochloric acid is supplied from the acid storage tank 1a to the cation exchange resin tower 3a and passed through the cation exchange resin tower 3a to obtain sodium chloride (NaC).
A recycled effluent containing 1) and unconsumed hydrochloric acid (HCl) is produced.

On the other hand, when caustic soda (NaOH) is supplied from the alkali storage tank 2a to the anion exchange resin tower 4a and passed through the anion exchange resin tower 4a, sodium chloride (N
aCl) and unconsumed caustic soda (NaOH) are produced as reclaimed effluent.

This regenerated waste liquid is supplied to the neutralization tank 5a, and hydrochloric acid or caustic soda for neutralization is injected to further neutralize unconsumed caustic soda or hydrochloric acid, and is discharged as a sodium chloride solution.

[0010]

However, in such a system, the hydrochloric acid or caustic soda stored in the acid storage tank 1a or the alkaline storage tank 2a and used for the regeneration of the ion exchange resin, and the unconsumed hydrochloric acid or caustic soda are However, since they are neutralized and discharged as they are without being reused, the amounts of these chemicals such as hydrochloric acid and caustic soda inevitably increase.

Further, in order to carry out the neutralization treatment, it is necessary to separately use an acid or alkaline solution.

The present invention has been made to solve the above problems, and is intended to reduce the amount of chemicals such as acid and alkali used for the regeneration of the ion exchange resin and to neutralize the waste waste liquid. It is an object of the present invention to reduce the amount of acid and alkali in the solution, reduce the equipment for neutralization, and eventually downsize the equipment for regenerating the ion exchange resin.

[0013]

In order to solve such a problem, the present invention has been made as a method and an apparatus for treating ion-exchange resin recycled wastewater. The characteristics of the method as a recycled wastewater are as follows: An acid is supplied to the cation exchange resin tower 3 and an alkaline solution is supplied to the anion exchange resin tower 4, and the cation exchange resin tower 3 and the anion exchange resin tower 4 are supplied.
The ion-exchange resin-regenerated wastewater after passing through is supplied to a bipolar membrane device 6 equipped with a cation-exchange membrane 7, an anion-exchange membrane 8 and a bipolar membrane 9, and the acid obtained after passing through the bipolar membrane device 6 The cation exchange resin tower 3 and the anion exchange resin tower 4 are separately separated from the alkali solution.
To send it back to.

Another feature of the method for treating reclaimed wastewater is that the acid and alkali solution are supplied to a mixed bed column 17 filled with a cation exchange resin and an anion exchange resin, and the mixed bed column 17 is supplied. The ion-exchange resin-regenerated wastewater after passing through is supplied to a bipolar membrane device 6 equipped with a cation-exchange membrane 7, an anion-exchange membrane 8 and a bipolar membrane 9, and the acid obtained after passing through the bipolar membrane device 6 This is to separate the alkali solution and the alkali solution separately and return them to the cation exchange resin tower 3 and the anion exchange resin tower 4.

Further, the features of the treatment apparatus for reclaimed wastewater are that an acid storage tank 1 for storing an acid, an alkali storage tank 2 for storing an alkaline solution, and an acid supplied from the acid storage tank 1 are passed through. A cation exchange resin tower 3 for producing regenerated wastewater containing neutral salt, and an anion exchange resin tower 4 for producing regenerated wastewater containing neutral salt by passing the alkaline solution supplied from the alkali storage tank 2. , A cation exchange membrane 7, an anion exchange membrane 8 and a bipolar membrane 9 are provided to separate the ion exchange resin regeneration wastewater after passing through the cation exchange resin tower 3 and the anion exchange resin tower 4 into an acid and an alkaline solution. And a bipolar membrane device 6 connected to the acid storage tank 1 and the alkali storage tank 2 in order to return the separated acid and alkali solution to the acid storage tank 1 and the alkali storage tank 2. Become In the door.

Another feature of the apparatus for treating reclaimed wastewater is that the acid storage tank 1 stores the acid, the alkali storage tank 2 stores the alkaline solution, and the acid and the alkali supplied from the acid storage tank 1. Mixed bed tower for passing alkaline solution supplied from storage tank 2 to produce regenerated wastewater containing neutral salt
17, a cation exchange membrane 7, an anion exchange membrane 8 and a bipolar membrane 9 are provided to separate the ion exchange resin regeneration wastewater after passing through the mixed bed tower 17 into an acid and an alkaline solution, and the separated It is provided with a bipolar membrane device 6 connected to the acid storage tank 1 and the alkali storage tank 2 in order to return the acid and the alkaline solution to the acid storage tank 1 and the alkali storage tank 2.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below.

Embodiment 1 FIG. 1 is a schematic block diagram of an apparatus for treating ion-exchange resin recycled wastewater as one embodiment.

In FIG. 1, 1 is an acid storage tank, 2 is an alkali storage tank, and hydrochloric acid and caustic soda are stored in the acid storage tank 1 and the alkali storage tank 2, respectively.

Reference numeral 3 denotes a cation exchange resin tower filled with a cation exchange resin, and 4 denotes an anion exchange resin tower filled with an anion exchange resin, which are downstream of the acid storage tank 1 and the alkali storage tank 2, respectively. It is installed in.

Reference numeral 5 denotes a neutralization tank for storing the recycled waste liquid after passing through the cation exchange resin tower 3 and the anion exchange resin tower 4 and for neutralizing unused hydrochloric acid and caustic soda in the recycled waste liquid. And, it is installed on the downstream side of the cation exchange resin tower 3 and the anion exchange resin tower 4.

Reference numeral 6 denotes a bipolar membrane device for separating and recovering the neutral salt in the neutralization tank 5 into an acid and an alkaline solution, and as shown in FIG. 2, a cation exchange membrane 7 and an anion. It is composed of an exchange membrane 8 and a bipolar membrane 9. The acid line 12 of the bipolar membrane device 9 is connected to the acid storage tank 1, and the alkali line 13 of the bipolar membrane device 6 is connected to the alkali storage tank 2. There is.

In FIG. 2, 14 is a neutral salt line and 10, 11
Indicates an anode and a cathode, and 15 indicates an electrode liquid line, respectively.

The ion-exchange resin regeneration wastewater treatment apparatus having the above-mentioned structure is used in the cation-exchange resin tower 3 described above.
And a decarbonation tower 16 installed between the anion exchange resin tower 4 and the anion exchange resin tower 4, in the deionization tower when regenerating the cation exchange resin tower 3 and the anion exchange resin tower 4. The connection between 16 and both ion exchange resin towers 3 and 4 is released, and both ion exchange resin towers 3 and 4 are connected to the above acid storage tank 1, alkali storage tank 2, neutralization tank 5, bipolar membrane device 6 and the like. It has been replaced.

Next, an explanation will be given of the case of treating the recycled wastewater by using the ion exchange resin recycled wastewater treatment apparatus having the above constitution.

First, hydrochloric acid is supplied from the acid storage tank 1 to the cation exchange resin tower 3.

The regenerated waste liquid obtained by passing the hydrochloric acid through the cation exchange resin tower 3 contains sodium chloride (NaCl) produced by the ion exchange reaction, but was not ion-exchanged and was not consumed. It also contains hydrochloric acid (HCl).

On the other hand, caustic soda (NaOH) is supplied from the alkali storage tank 2 to the anion exchange resin tower 4.

The reclaimed waste liquid obtained by passing the caustic soda through the anion exchange resin tower 4 contained sodium chloride (NaCl) produced by the ion exchange reaction, but was not ion-exchanged and was not consumed. It also contains caustic soda.

Therefore, the regenerated waste liquid generated from both ion-exchange resin towers 3 and 4 contains hydrochloric acid and caustic soda in addition to sodium chloride, and they are all supplied to the neutralization tank 5. Becomes

In this neutralization tank 5, hydrochloric acid or caustic soda for neutralization is added to neutralize unconsumed caustic soda or hydrochloric acid.

Next, the sodium chloride from the neutralization tank 5 is
It is supplied to the bipolar membrane device 6 and separated into hydrochloric acid and caustic soda by the bipolar membrane device 6.

To explain this in more detail, the solution containing sodium chloride (NaCl) supplied from the neutralization tank 5 to the bipolar membrane device 6 passes through the neutral salt line 14 of the bipolar membrane device 6. , At this time neutral salt line 14
As shown in FIG. 2, NaCl in the inside is Na ⁺ ions and Cl ^−.
It is ionized with ions.

The cation Na ⁺ moves to the alkali line 13 side through the cation exchange membrane 7, and the anion Cl ⁻ passes through the anion exchange membrane 8 to the acid line 12 side.
Move to the side.

On the other hand, part of the water existing in the alkaline line 13 and the acid line 12 which come into contact with the bipolar film 9 penetrates into the bipolar film 9 and is ionized into H ⁺ and OH ^−, and H ⁺ is the cathode. Side, and OH ⁻ moves to the anode side.

Therefore, H ⁺ ionized in the bipolar film 9 is
Is an acid line through the cation exchange side of the bipolar membrane 9.
12 and moves to the acid line 12 to combine with the Cl ⁻ obtained as described above to produce HCl.
Cl will be returned from the acid line 12 to the acid storage tank 1 as described above and recovered.

OH ⁻ ionized in the bipolar film 9
Moves to the alkali line 13 side through the anion-exchange side of the bipolar membrane 9 and is combined with the Na ⁺ obtained as described above in the alkali line 13 to produce NaOH. It is recovered from 13 in the alkaline storage tank 3 as described above.

On the other hand, in the neutral salt line 14, NaCl passes in a desalted state (not shown).

In the neutral salt line 14, Na ⁺ and Cl ^−.
Move to alkali line 13 and acid line 12, respectively,
The concentration is reduced due to the consumption of NaCl, and the unconsumed NaCl is collected in the neutralization tank 5 (not shown).

As described above, in this embodiment, sodium chloride (NaCl), which is a neutral salt in the regenerated waste liquid that has passed through the cation exchange resin tower 3 and the anion exchange resin tower 4, is converted into hydrochloric acid by the bipolar membrane device 6. HCl) and caustic soda (NaOH) are separately collected and returned to the acid storage tank 1 and the alkali storage tank 2, respectively. It can be reused, and the amount of hydrochloric acid or caustic soda to be purchased as a chemical can be reduced. Embodiment 2

FIG. 3 is a schematic block diagram of an ion exchange resin regeneration wastewater treatment apparatus as another embodiment of the present invention.

In this embodiment, a mixed bed column in which one of the cation exchange resin and the anion exchange resin is packed in place of the cation exchange resin column 3 and the anion exchange resin column 4 is used. The difference from the first embodiment is that 17 is installed.

That is, in this embodiment, both the acid storage tank 1 and the alkali storage tank 2 are connected to the mixed bed tower 17, and the mixed bed tower 17 is connected to the neutralization tank 5.

Connection between the neutralization tank 5 and the bipolar membrane device 6, the bipolar membrane device 6, the acid storage tank 1 and the alkaline storage tank 2
Since the connection with is the same as in the first embodiment,
The description is omitted.

In this embodiment, hydrochloric acid from the acid storage tank 1
Caustic soda is supplied to the mixed bed tower 17 from the alkali storage tank 2.

Hydrochloric acid is ion-exchanged by the cation exchange resin in the mixed bed tower 17, and caustic soda is ion-exchanged by the anion exchange resin in the mixed bed tower 17.

Then, the recycled waste liquid after passing through the mixed bed tower 17 contains sodium chloride as in the first embodiment.

Since the supply of the sodium chloride solution from the neutralization tank 5 to the bipolar membrane 6 and the separation and recovery of chlorine and caustic soda in the bipolar membrane 6 and the return are the same as those in the first embodiment, the details thereof will be described. Detailed description is omitted.

Embodiment 3 FIG. 4 is a schematic block diagram of an ion exchange resin regeneration wastewater treatment apparatus as another embodiment of the present invention.

This embodiment differs from the first embodiment in that an electrodialysis device 18 is provided between the neutralization tank 5 and the bipolar membrane device 6.

In general, when producing purified water or the like, tap water, which is treated water, may contain magnesium ions and calcium ions. Such treated water is treated using an ion exchange resin tower. In that case, magnesium ions and calcium ions will be adsorbed by the ion exchange resin in the ion exchange resin tower.

Therefore, when regenerating the ion exchange resin tower, the regeneration waste liquid after passing through the ion exchange resin tower contains magnesium ions and calcium ions.

In this embodiment, the regenerated waste liquid containing sodium chloride in the neutralization tank 5 is supplied to the bipolar membrane device 6 before the monovalent cation selective permeable cation exchange membrane and the anion selective permeable membrane. Is supplied to the electrodialysis device 18 equipped with the anion exchange membrane.

Therefore, even if the regeneration waste liquid containing sodium chloride contains magnesium ions and calcium ions as described above, when such regeneration waste liquid enters the electrodialysis device 18, the electrodialysis device 18 Only monovalent sodium ions are selectively permeated by the ion exchange membrane in the inside, sodium chloride is supplied from the electrodialysis device 18 to the bipolar membrane device 6, and divalent ions such as magnesium ions and calcium ions are ionized. Does not permeate through the exchange membrane,
It is discharged from the electrodialysis device 18 to the outside of the system.

Therefore, even if the waste water is repeatedly regenerated,
Since magnesium ions and calcium ions are discharged out of the system by the electrodialysis device 18 as described above, it is possible to prevent magnesium and calcium from accumulating and causing scaling.

In particular, in the closed system system as in this embodiment, the effect of preventing the occurrence of scaling associated with the accumulation of magnesium and calcium is extremely useful.
The total concentration of magnesium and calcium in the system at this time is preferably 100 ppm or less, more preferably 50 ppm or less.

Since other configurations and operations are the same as those in the first embodiment, detailed description will be omitted.

Embodiment 4 FIG. 6 shows a schematic block diagram of an ion-exchange resin regeneration wastewater treatment apparatus as another embodiment of the present invention.

The present embodiment is different from the third embodiment in that a reverse osmosis membrane device 19 is used instead of the electrodialysis device 18.
The reverse osmosis membrane device 19 is generally loose RO or NF.
A reverse osmosis membrane device called (nanofilter) was used.

Also by the reverse osmosis membrane device 19 in this embodiment, only sodium ions are selectively permeated, and divalent ions such as magnesium ions and calcium ions are not permeated, and the electrodialysis is carried out outside the system. It has the same function as the device 18.

Therefore, also in this embodiment, the effect of preventing the accumulation of magnesium and calcium and the effect of preventing the occurrence of scaling can be obtained. In the present embodiment as well, similarly to the third embodiment, the total concentration of magnesium and calcium is 100 ppm or less, preferably 50 ppm or less.

Other Embodiments Since the electrodialysis device 18 and the reverse osmosis device 19 are provided in the third and fourth embodiments, it is possible to prevent scaling due to accumulation of magnesium and calcium. However, the provision of such electrodialysis device 18 and reverse osmosis membrane device 19 is not an essential condition for the present invention.

However, since it is likely that the treated water contains magnesium ions and calcium ions, it is extremely useful to provide the electrodialysis device 18 and the reverse osmosis membrane device 19 as described above.

By the way, there is a method of using a chelate resin as a means for removing such magnesium and calcium, but when such a chelate resin is used, there is a drawback that the removal performance is lost when operating for a long time. is there. And in order to recover such removal performance,
The chelating resin must be regenerated and the equipment must be shut down as a result.

However, in Embodiments 3 and 4 as described above, since the electrodialysis device 18 and the reverse osmosis device 19 are used, the removal performance is not lost even if the device is operated for a long time.
Since the problem of regenerating the chelate resin as described above does not occur, it is not necessary to stop the apparatus, and there is an advantage that continuous operation is possible.

In the above embodiment, hydrochloric acid was used as the acid for regenerating the cation exchange resin, and caustic soda was used as the alkaline solution for regenerating the anion exchange resin. It is not limited, and it is also possible to use an acid other than hydrochloric acid or an alkaline solution other than caustic soda.

Therefore, the type of neutral salt contained in the recycled waste liquid is not limited to sodium chloride.

Further, as in the second embodiment, the apparatus using the mixed bed column 17 can be equipped with the electrodialysis apparatus 18 used in the third embodiment and the reverse osmosis membrane apparatus 19 used in the fourth embodiment. Is.

[0069]

INDUSTRIAL APPLICABILITY As described above, in the present invention, the neutral salt in the regenerated waste liquid that has passed through the cation exchange resin column and the anion exchange resin column or has passed through the mixed bed column is transferred by the bipolar membrane device. Separated and recovered in acid and alkaline solution,
Since it is returned to the acid storage tank or alkali storage tank, it is possible to reuse chemicals such as acids and alkaline solutions used to regenerate the ion exchange resin, reducing the purchase amount of chemicals for regeneration. It has the effect of

Further, since the acid or alkali solution separated and recovered by the bipolar membrane can be returned to the acid storage tank or the alkali storage tank for circulation and used, the amount of regeneration waste liquid discharged outside the system as a so-called closed system can be reduced. As a result, there is an effect that the cost required for waste liquid treatment can be reduced.

Further, there is an effect that the amount of acid or alkali solution for neutralizing the recycled waste liquid can be reduced, and as a result, equipment such as a neutralization tank can be downsized.

Further, when an electrodialysis device or a reverse osmosis device is installed between the neutralization tank and the bipolar membrane device, monovalent ions such as sodium permeate and divalent magnesium ions and calcium ions permeate. Therefore, there is an effect that it is possible to prevent accumulation of magnesium and calcium due to repeated regeneration processing, and eventually, occurrence of scaling.

[Brief description of the drawings]

FIG. 1 is a schematic block diagram of an ion exchange resin regeneration wastewater treatment apparatus as one embodiment.

FIG. 2 is a schematic diagram of a bipolar membrane device used in a recycled wastewater treatment device.

FIG. 3 is a schematic block diagram of an ion exchange resin regeneration wastewater treatment apparatus according to another embodiment.

FIG. 4 is a schematic block diagram of an ion exchange resin regeneration wastewater treatment apparatus as another embodiment.

5 is a schematic diagram of an electrodialysis device used in the recycled wastewater treatment device of FIG.

FIG. 6 is a schematic block diagram of an ion exchange resin regeneration wastewater treatment apparatus as another embodiment.

FIG. 7 is a schematic block diagram of a pure water production apparatus.

FIG. 8 is a schematic block diagram of a conventional recycling wastewater treatment device for ion exchange resins.

[Explanation of symbols]

3 ... Cation exchange resin tower 4 ... Anion exchange resin tower 5 ... Neutralization tank 6 ... Bipolar membrane device 7 ... Cation exchange membrane 8 ... Anion exchange membrane 9 ... Bipolar membrane 17 ... Mixed bed tower 18 ... Electrodialysis device 19 ... Reverse osmosis device

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location C02F 1/469 C02F 1/46 103

Claims (6)

[Claims] 1. An acid is supplied to a cation exchange resin tower (3) and an alkaline solution is supplied to an anion exchange resin tower (4), and the cation exchange resin tower (3) and the anion exchange resin tower are supplied.
The ion-exchange resin regeneration wastewater after passing through (4) is supplied to a bipolar membrane device (6) equipped with a cation-exchange membrane (7), an anion-exchange membrane (8) and a bipolar membrane (9), Ions characterized by separately separating the acid and the alkaline solution obtained after passing through the membrane device (6) and returning them to the cation exchange resin tower (3) and the anion exchange resin tower (4) Method for treating waste resin recycled wastewater. 2. An acid and an alkaline solution are supplied to a mixed bed tower (17) packed with a cation exchange resin and an anion exchange resin, and the ion exchange resin is regenerated after passing through the mixed bed tower (17). Waste water was supplied to a bipolar membrane device (6) equipped with a cation exchange membrane (7), an anion exchange membrane (8) and a bipolar membrane (9), and was obtained after passing through the bipolar membrane device (6). A method for treating ion-exchange resin recycled wastewater, characterized in that the acid and the alkaline solution are separated separately and returned to the mixed bed tower (17). 3. An electrodialysis device (18) or a reverse osmosis membrane device (19) capable of blocking permeation of divalent ions before supplying the ion exchange resin regenerated wastewater to the bipolar membrane device (6).
The method for treating ion-exchange resin recycled wastewater according to claim 1 or 2, wherein the water is passed through in advance. 4. An acid storage tank (1) for storing an acid, an alkali storage tank (2) for storing an alkaline solution, and the acid storage tank
The cation exchange resin tower (3) that passes the acid supplied from (1) to generate regenerated wastewater containing neutral salt, and the alkali solution supplied from the alkali storage tank (2) to Anion-exchange resin tower for producing recycled wastewater containing volatile salt
(4), a cation exchange membrane (7), an anion exchange membrane (8), and a bipolar membrane (9) are provided after passing through the cation exchange resin tower (3) and the anion exchange resin tower (4). The ion storage resin regeneration wastewater of 1 is separated into an acid and an alkali solution, and the separated acid and alkali solution are returned to the acid storage tank (1) and the alkali storage tank (2). (1) and a bipolar membrane device (6) connected to an alkali storage tank (2), A treatment device for ion-exchange resin recycled wastewater, comprising: 5. An acid storage tank (1) for storing an acid, an alkali storage tank (2) for storing an alkaline solution, and the acid storage tank
A mixed bed tower (17) that produces recycled wastewater containing neutral salts by passing the acid supplied from (1) and the alkaline solution supplied from the alkali storage tank (2), and a cation exchange membrane (7) A mixed bed tower equipped with an anion exchange membrane (8) and a bipolar membrane (9)
(17) the ion-exchange resin regeneration wastewater obtained by passing through is separated into an acid and an alkaline solution, and the separated acid and alkaline solution are the acid storage tank (1) and the alkali storage tank (2) Acid storage tank (1) and alkali storage tank (2) to be returned to
And a bipolar membrane device (6) connected to the ion exchange resin recycled wastewater treatment device. 6. The electrodialysis device (18) or the reverse osmosis membrane device (19) capable of blocking the permeation of divalent ions is installed upstream of the bipolar membrane device (6). 5. The ion exchange resin reclaimed wastewater treatment device according to 5.