JP7040008B2 - TOC removal device - Google Patents

Description

The present invention relates to a TOC removing device and a TOC removing method, and more particularly, to a TOC removing device and a TOC removing method for more easily and continuously decomposing and removing a TOC containing a persistent TOC in TOC-containing water.

High-concentration chemicals and detergents and large amounts of pure water and ultrapure water for rinsing them are used for cleaning and surface treatment of electronic parts. For this reason, not only the improvement of the water quality of ultrapure water with the sophistication of electronic parts, but also the improvement of the water recovery rate by wastewater recovery aimed at reducing the amount of water used has become an issue. Among them, it is an important issue to efficiently reduce the organic matter component (TOC) in water to a lower concentration in terms of both improvement of water quality and improvement of water recovery rate.

There are two methods for decomposing TOC: biological treatment and physicochemical treatment. When biological treatment is difficult to apply, for example, removal using a reverse osmosis (RO) membrane or combined use with an oxidizing agent is used among the physicochemical treatments. Low-pressure UV oxidizers using thermal decomposition and low-pressure UV lamps have been used.

However, these methods require a large amount of electrical energy (driving power of RO membrane water supply pressurizing pump, UV irradiation power, etc.) and thermal energy (steam of heat decomposition device, etc.).
In addition, RO membranes and low-pressure UV oxidizing equipment, which are often used in ultrapure water production equipment, are extremely decomposable for TOC called persistent TOC represented by nitrogen compounds (urea, etc.) with a small molecular weight. There was also the problem of inefficiency.

To solve these problems, the present inventor has proposed a method for removing TOC using a catalyst in Patent Document 1.
This method is a method in which a hydrogen water water flow step, an oxygen water water flow step, and an organic substance-containing raw water water flow step are repeatedly performed on a platinum group metal catalyst, and the TOC is decomposed by the following mechanism.
When hydrogen water is passed through the catalyst, hydrogen is adsorbed on the catalyst. By supplying oxygenated water with hydrogen adsorbed on the catalyst, water molecules are generated on the catalyst, and some water molecules stay on the catalyst. Next, when organic substance-containing water is supplied, a TOC such as urea having an unshared electron pair and the water molecule form a bond such as a coordinate bond, and the organic substance is adsorbed on the catalyst. This adsorbed organic substance is partially decomposed by the action of the platinum group catalyst. Then, at the time of the next supply of hydrogen water, hydrogen is adsorbed on the catalyst and at the same time, the decomposition product is separated from the catalyst.
By contacting the treated water after contacting with the catalyst in this way with at least one of the anion exchange resin and the cation exchange resin, ionic substances such as organic acids generated by the decomposition of TOC are adsorbed and removed by the ion exchange resin. can. Therefore, in Patent Document 1, an ion exchange resin column is provided after the catalyst-filled column.

The continuous electric deionization device used in the present invention is deionized water used in various industries such as semiconductor manufacturing factories, liquid crystal manufacturing factories, pharmaceutical industries, food industries, electric power industries, etc., or in consumer or research facilities. Widely used in manufacturing. In the continuous electrodeionization device, as shown in FIG. 2, a plurality of anion exchange membranes 13 and cation exchange membranes 14 are alternately arranged between the electrodes (anodide 11 and cathode 12), and the concentration chamber 15 and the desalting chamber 16 are arranged. And are alternately formed, and the desalting chamber 16 is mixed or filled with an anion exchanger and a cation exchanger made of an ion exchange resin, an ion exchange fiber, a graft exchanger, or the like in a mixed or multi-layered manner. In FIG. 2, 17 is an anode chamber and 18 is a cathode chamber.
The continuous electrodeionizer enables efficient deionization by generating H ⁺ ions and OH ^- ions by water dissociation and continuously regenerating the ion exchanger packed in the desalination chamber. It has the excellent feature that it does not require regeneration treatment using chemicals such as the ion exchange resin device that has been widely used in the past, complete continuous water sampling is possible, and high-purity water can be obtained. ..

Japanese Unexamined Patent Publication No. 2013-208557

In the method of Patent Document 1, it is necessary to switch between the hydrogen water water flow process, the oxygen water water flow process, and the raw water water flow process, and there is a problem that pressure fluctuation occurs. Further, when the ionic substance generated by the treatment of raw water is adsorbed on the ion exchange resin and removed, the ion exchange resin needs to be replaced or regenerated, so that there is a problem in continuous processability.

An object of the present invention is to provide a TOC removing device and a TOC removing method capable of more easily and continuously decomposing and removing TOC in TOC-containing water including hardly decomposable TOC.

As a result of diligent studies to solve the above problems, the present inventors have filled the desalting chamber of the continuous electrodeionizer with a catalyst having TOC resolution together with an anion exchanger and a cation exchanger. It has been found that the TOC can be easily and continuously decomposed and removed, including the persistent TOC, without the need for switching the water flow or exchanging or regenerating the ion exchange resin.
That is, the desalting chamber of the continuous electrodeionizer is filled with a catalyst having TOC resolution together with the anion exchanger and the cation exchanger, and the water supplied to the continuous electrodeionizer is hydrogen gas-dissolved TOC-containing water and oxygen. By alternately switching between the gas solution and the TOC-containing water, the TOC is adsorbed (when the oxygen gas-dissolved TOC-containing water is supplied) and desorbed (hydrogen gas-dissolved TOC-containing water supply) to the catalyst having the TOC resolution in the continuous electric deionizer. Time) can be repeated continuously, and the TOC decomposition product such as urea ionized at the time of desorption is adsorbed by the ion exchanger in the desalination chamber, and the ion exchanger adsorbing the TOC decomposition product is continuously electrodeionized. By continuously regenerating with the original operation of the device, it becomes possible to continuously perform water treatment.

The present invention has been achieved based on such findings, and the gist of the present invention is as follows.

[1] A TOC removing device comprising a continuous electric deionizing device including a catalyst having TOC resolution in a desalting chamber.

[2] The continuous electricity of a gas dissolving means for dissolving hydrogen gas or oxygen gas in TOC-containing water, a TOC-containing water in which hydrogen gas is dissolved by the gas dissolving means, and a TOC-containing water in which oxygen gas is dissolved. The TOC removing device according to [1], which comprises means for alternately introducing the deionizing device into the desalting chamber.

[3] The gas dissolving means includes a gas dissolving film module provided in front of the continuous electric deionizing device, a hydrogen gas supplying means for supplying hydrogen gas to the gas phase chamber of the gas dissolving film module, and the gas. An oxygen gas supply means for supplying oxygen gas to the shared chamber, a switching means for alternately switching the gas supply by the hydrogen gas supply means and the oxygen gas supply means, and the TOC-containing water in the liquid phase chamber of the gas dissolution film module. The TOC removal according to [2], wherein the gas-dissolved TOC-containing water flowing out of the liquid phase chamber is introduced into the desalting chamber of the continuous electrodeionizer. Device.

[4] An oxygen gas feeding means that feeds an oxygen gas generated at the anode of the continuous electrodeionizer to the gas dissolving means as an oxygen gas that dissolves the TOC-containing water, and / or the continuous electricity. [2] or [3], wherein the gas feeding means for feeding the hydrogen gas generated at the cathode of the deionizer to the gas dissolving means as the hydrogen gas for dissolving the hydrogen gas in the TOC-containing water is provided. TOC removal device.

[5] The TOC removing apparatus according to any one of [1] to [4], wherein the catalyst having TOC resolution is made of fine particles of a platinum group metal and is supported on an ion exchange resin.

[6] The desalting chamber of the continuous electrodeionizer is filled with a cation exchange resin and an anion exchange resin on which a metal having TOC resolution is supported [1] to [1]. 5] The TOC removing device according to any one of.

[7] A method for decomposing and removing TOC in TOC-containing water includes a hydrogen gas dissolution step of dissolving hydrogen gas in the TOC-containing water and an oxygen gas dissolution step of dissolving oxygen gas in the TOC-containing water. In the desalting chamber of the TOC removing device according to any one of [1] to [6], the hydrogen gas-dissolved TOC-containing water from the hydrogen gas dissolution step and the oxygen gas-dissolved TOC-containing water from the oxygen gas dissolution step. A TOC removing method, which comprises alternately introducing and removing the TOC in the TOC-containing water.

According to the present invention, it is possible to more easily and continuously decompose and remove TOC including persistent TOC in TOC-containing water.

It is a system diagram which shows the embodiment of the TOC removal apparatus of this invention. It is a schematic sectional drawing which shows the general structure of the continuous electric deionization apparatus.

Hereinafter, embodiments of the TOC removing device and the TOC removing method of the present invention will be described in detail.

The TOC removing device of the present invention is a continuous electrodeionization device in which a desalting chamber is filled with an anion exchanger and a cation exchanger and a catalyst having TOC resolution (hereinafter, "continuous electrodeionization device of the present invention"). It may be referred to as).
The member configuration itself of the continuous electric deionizing device of the present invention is the same as the general continuous electric deionizing device shown in FIG. 2, and the continuous electric deionizing device of the present invention is the continuous electric deionizing device. The desalting chamber is filled with a catalyst having TOC resolution.

As described above, in the continuous electrodeionization device, as shown in FIG. 2, a plurality of anion exchange films 13 and cation exchange films 14 are alternately arranged between the electrodes (anodide 11 and cathode 12) to form a concentration chamber 15. The desalting chambers 16 are alternately formed, and the desalting chamber 16 is filled with an anion exchanger and a cation exchanger made of an ion exchange resin, an ion exchange fiber, a graft exchanger, or the like in a mixed or multi-layered manner.
The continuous electrodeionizer of the present invention comprises a desalting chamber of such a general continuous electrodeionizer filled with an anion exchanger and a cation exchanger and a catalyst having TOC resolution. As the filling method,
(1) A catalyst having TOC resolution is filled in a part of the desalting chambers among the plurality of desalting chambers, and an anion exchanger and a cation exchanger are filled in the other desalting chambers.
(2) A catalyst having TOC resolution and an anion exchanger and a cation exchanger are filled in a part of a plurality of desalting chambers, and an anion exchanger and a cation exchanger are filled in the other desalting chambers.
(3) All desalting chambers are filled with a catalyst having TOC resolution and an anion exchanger and a cation exchanger.
However, since the TOC of the water to be treated that does not come into contact with the catalyst having the TOC resolution is not decomposed, it is preferable to fill the catalyst having the TOC resolution by the method (3).

The catalyst having a TOC resolution may be any catalyst having a TOC resolution, and is not particularly limited, but it is preferable to use a platinum group metal catalyst because it is also excellent in a persistent TOC resolution.
Examples of the platinum group metal used in the catalyst include ruthenium, rhodium, palladium, osmium, iridium and platinum. These platinum group metals can be used alone, in combination of two or more, as alloys of two or more, or as a naturally occurring mixture. The product can also be used without being separated into individual pieces. Among these, platinum, palladium, a platinum / palladium alloy alone or a mixture of two or more of them has strong catalytic activity and can be particularly preferably used.

The platinum-group metal catalyst may be platinum-group metal fine particles, or may be a metal-supported catalyst in which platinum-group metal nanocolloidal particles are supported on the surface of a carrier.

The average particle size of the platinum group metal nanocolloidal particles is preferably 1 to 50 nm, more preferably 1.2 to 20 nm, and even more preferably 1.4 to 5 nm. If the average particle size of the metal nanocolloidal particles is less than 1 nm, the catalytic activity for decomposition and removal of TOC may decrease. If the average particle size of the metal nanocolloidal particles exceeds 50 nm, the specific surface area of the nanocolloidal particles becomes small, and the catalytic activity for decomposition and removal of TOC may decrease.

The carrier on which the platinum group metal nanocolloidal particles are supported is not particularly limited, and examples thereof include magnesia, titania, alumina, silica-alumina, zirconia, activated carbon, zeolite, diatomaceous earth, and ion exchange resin. Among these, anion exchange resin can be particularly preferably used. Since the platinum group metal nanocolloidal particles have an electric double layer and are negatively charged, they are stably supported by the anion exchange resin and are difficult to peel off. The anion exchange resin is preferably a strong basic anion exchange resin based on a styrene-divinylbenzene copolymer, and more preferably a gel type resin. Further, the exchange group of the anion exchange resin is preferably OH type.

The amount of the platinum group metal nanocolloidal particles carried on the anion exchange resin is preferably 0.01 to 0.2% by weight, more preferably 0.04 to 0.1% by weight. If the supported amount of the metal nanocolloidal particles is less than 0.01% by weight, the catalytic activity for decomposition and removal of TOC may be insufficient. When the amount of the metal nanocolloidal particles supported is 0.2% by weight or less, sufficient catalytic activity is exhibited for the decomposition and removal of TOC, and it is usually not necessary to support the metal nanocolloidal particles exceeding 0.2% by weight. In addition, as the amount of metal nanocolloidal particles supported increases, the risk of metal elution into water also increases.

The filling amount of the catalyst having the TOC resolution in the desalting chamber is not particularly limited, and is appropriately adjusted according to the required TOC resolution.

Examples of the anion exchanger and the cation exchanger filled in the desalting chamber of the continuous electrodeionizer of the present invention include an ion exchange resin, an ion exchange fiber, a graft exchanger and the like, and the anion exchange resin is preferable. And ion exchange resin.

The filling ratio of the anion exchanger and the cation exchanger in the desalting chamber is not particularly limited, but usually, the anion exchanger: the cation exchanger is filled at 1: 1 to 7: 3 (volume ratio).

As described above, since it is preferable to use a platinum group metal catalyst supported on an anion exchange resin as a catalyst having TOC resolution, the continuous electrodeionizer of the present invention has anion exchange in a desalting chamber. By using a resin filled with the above-mentioned platinum group metal-supported anion exchange resin instead of the conventional ordinary anion exchange resin, a catalyst having TOC decomposability can be sufficiently filled and the platinum group can be sufficiently filled. This is a preferred embodiment because the catalyst having TOC resolution and the anion exchanger can be filled only by filling the metal-supported anion exchange resin.

In this case, since the catalyst having the TOC resolution occurs only on the surface, the anion exchange capacity inside the anion exchange resin remains. Therefore, even if the anion exchange resin filled in the desalting chamber of the continuous electrodeionizer is used as the above-mentioned metal catalyst-supported anion exchange resin, the ion exchange ability is not impaired.

In the continuous electrodeionization apparatus of the present invention, the concentration chamber may also be filled with an anion exchanger and a cation exchanger.

As described in Patent Document 1, in order to decompose TOC by a catalyst having TOC resolution, it is necessary to supply hydrogen in advance and then oxygen.
Therefore, in the TOC removing device of the present invention, a gas dissolving means for dissolving hydrogen gas or oxygen gas in the TOC-containing water which is raw water, and the TOC-containing water and oxygen gas in which hydrogen gas is dissolved by the gas dissolving means are dissolved. It is preferable to provide a means for alternately introducing the TOC-containing water into the desalting chamber of the continuous electrodeionizer of the present invention. As this gas dissolution means, a gas dissolution film module is provided in front of the continuous electric deionization device, and a hydrogen gas supply means for supplying hydrogen gas to the gas phase chamber of the gas dissolution film module and an oxygen gas supply means for supplying oxygen gas. A switching means for alternately switching the gas supply by the hydrogen gas supply means and the oxygen gas supply means, and a means for supplying TOC-containing water to the liquid phase chamber of the gas dissolution film module are provided, and the liquid phase of the gas dissolution film module is provided. It is preferable to introduce the gas-dissolved TOC-containing water flowing out of the chamber into the desalting chamber of the continuous electrodeionizer.
As described above, in the method of Patent Document 1, it was necessary to repeatedly carry out the hydrogen water passing step, the oxygen water passing step and the organic substance-containing raw water passing step, whereas in the present invention, hydrogen gas and oxygen gas are used. Since it is possible to alternately pass hydrogen water and oxygen water by switching between, the TOC can be decomposed and removed by alternating water passing between the hydrogen gas-dissolved TOC-containing water and the oxygen gas-dissolved TOC-containing water.

Further, in the continuous electric deionizer, since a DC voltage is applied to water, oxygen is generated at the anode and hydrogen is generated at the cathode, so that the oxygen gas generated at the anode is dissolved in the TOC-containing water of the raw water. As the gas, it is preferable that the hydrogen gas generated at the cathode is supplied to a gas dissolving means such as a gas dissolving film module as a hydrogen gas for dissolving the hydrogen gas generated in the raw water in the TOC-containing water of the raw water for effective use.

FIG. 1 is a system diagram showing an embodiment of the TOC removing device of the present invention incorporating such a preferred embodiment.
The raw water TOC removing device is supplied to the gas dissolving membrane module 1 which is a gas dissolving means via the raw water supply pipe L1. The gas dissolving means is not limited as long as it can dissolve the gas in the TOC-containing water, and a membrane, an ejector, an air diffuser, or the like is used. Here, the gas dissolution membrane module 1 which is easy to handle is exemplified. The raw water is appropriately dissolved with nitrogen gas and hydrogen gas or oxygen gas in the gas dissolution film module 1, and is continuously electrodeionized from the liquid phase chamber 1B of the gas dissolution film module 1 through the water supply pipe L2 as gas dissolution water. It is supplied to the device 2. The nitrogen gas in the nitrogen gas tank 3 is supplied as a carrier gas to the gas phase chamber 1A of the gas dissolution film module 1 via the nitrogen gas pipe L3 having the nitrogen gas flow rate adjusting valve V1 and the gas supply main L6. It is desirable to supply about 10 to 1000 NL / min of nitrogen gas depending on the type of the membrane of the gas dissolution membrane module 1, but this is not the case because it depends on the amount of water and the number of membranes. The supply of nitrogen gas has the meaning of dilution because hydrogen gas is explosive, but this is not the case if explosion-proof measures are taken.

The hydrogen gas in the hydrogen gas tank 5 is 0.1 to 4.0% by volume of the nitrogen gas flow rate, for example, about 1% by volume is gas through the hydrogen gas pipe L5 having the hydrogen gas flow rate adjusting valve V3 and the gas supply main L6. It is supplied to the gas phase chamber 1A of the dissolution film module 1. Since the explosion limit of hydrogen gas is 4% by volume or more of the nitrogen gas flow rate, the amount of hydrogen gas supplied is preferably about 1% by volume of the nitrogen gas flow rate for safety, but as described above, explosion-proof measures are taken. If so, that is not the case.

The oxygen gas in the oxygen gas tank 4 is supplied to the gas phase chamber 1A of the gas dissolution film module 1 via the oxygen gas pipe L4 having the oxygen gas flow rate adjusting valve V2 and the gas supply main L6. As for the supply amount of oxygen gas, it is desirable to supply 0.1 to 20% by volume of the nitrogen gas flow rate, for example, about 1% by volume, as in the case of hydrogen gas. L7 is an exhaust pipe from the gas phase chamber 1A of the gas dissolution membrane module 1.

In this way, hydrogen gas and oxygen gas are alternately supplied together with nitrogen gas as a carrier gas, and the supply to the continuous electrodeionizer 2 is supplied from hydrogen gas-dissolved raw water → oxygen gas-dissolved raw water → hydrogen gas-dissolved gas → oxygen. By alternately repeating the process of gas-dissolved raw water ..., the TOC can be absorbed and desorbed by the catalyst in the desalting chamber of the continuous electrodeionizer 2.
In addition, about 1/2 of the TOC is ionized during desorption, but the generated ionic decomposition product is repeatedly absorbed and desorbed by continuous water flow, so that the ion exchanger in the desalting chamber of the continuous electric deionizer 2 is used. It is trapped in the system and discharged to the outside of the system through the concentration chamber of the continuous electrodeionizer 2.

Here, the mechanism by which the TOC is attached to and detached from the catalyst having the TOC resolution is as follows.
First, when hydrogen gas-dissolved water is supplied to the metal catalyst, hydrogen is occluded in the catalyst, and a weak bond between the catalyst metal and hydrogen is formed on the surface. When the coexistence system of oxygen gas and TOC comes into contact with the metal catalyst in that state, when the hydrogen atom and the oxygen atom existing on the surface of the catalyst metal are bonded, the electrons in the oxygen atom are pulled in the hydrogen (metal) direction and become an electron. Is deficient, and it is thought that the unshared electron pair of TOC binds to it. It is thought that when hydrogen gas-dissolved water is brought into contact again in this state, desorption occurs from the oxygen atom, and a part of the TOC is ionized and desorbed. Therefore, it is necessary to alternately bring the hydrogen gas-dissolved water and the oxygen gas-dissolved water into contact with the metal catalyst, but it can be dealt with by switching the gas supply to the gas dissolving means between oxygen gas and hydrogen gas as described above. , It is not necessary to switch the water flow path, and it is possible to easily deal with it without accompanied by pressure fluctuations. In this case, the timing of alternately switching the gas is preferably about 1 to 600 seconds, particularly preferably about 10 to 300 seconds, and the oxygen gas supply time is about 0.5 to 2.0 times the hydrogen gas supply time. Is preferable.

First, hydrogen gas-dissolved raw water is supplied to the desalting chamber of the continuous electric deionization device 2. The TOC in the hydrogen gas-dissolved raw water supplied here flows out as it is because oxygen does not exist, but it is desirable to initially blow the treated water obtained by this initial water supply. In addition, when hydrogen gas-dissolved raw water and oxygen gas-dissolved raw water are alternately repeated, there is no problem because the TOC of the hydrogen gas-dissolved raw water is instantaneously absorbed and desorbed by passing through the resin layer on which oxygen is adsorbed. It is processed.

In this way, the TOC in the raw water was decomposed by the continuous electrodeionizer 1, and the ionic substances generated by the decomposition were removed by ion exchange by the ion exchanger in the desalination chamber. It is discharged to the outside of the system from the treated water discharge pipe L8 of the deionization device 1.

As described above, since the continuous electrodeionizer 2 applies a DC voltage to water, oxygen gas is generated at the anode and hydrogen gas is generated at the cathode. Therefore, the oxygen gas generated at the anode is dissolved in the raw water. In order to effectively utilize the hydrogen gas generated at the cathode as hydrogen gas for dissolving in raw water, in the TOC removing device of FIG. 1, the oxygen gas generated at the anode of the continuous electrodeionization device 2 is used in the oxygen gas exhaust pipe L9. It is configured to supply the hydrogen gas generated at the cathode to the oxygen gas tank 4 via the hydrogen gas exhaust pipe L10 and to the hydrogen gas tank 5 via the hydrogen gas exhaust pipe L10. L11 and L12 are pipes for exhausting each gas to the outside of the system.

According to such a TOC removing device of the present invention, TOC in TOC-containing water can be easily continuously treated including persistent TOC to be highly decomposed and removed. In particular, the present invention is suitable as a system for further reducing the concentration of TOC components in ultrapure water having a TOC concentration of about 1 to 10 ppb.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples.

In both the following examples and comparative examples, treatment was performed using TOC-containing water having a TOC concentration of 3 ppb containing urea as a TOC source as raw water at a flow rate of 1 m ³ / hr.

[Example 1]
Raw water was treated with the TOC removing device of the present invention shown in FIG.
The equipment specifications used in the test are as follows.
Gas dissolution membrane module: "Lixel G284" manufactured by Cellguard (4 x 28 inches)
Continuous electric deionization device: "CKDI" manufactured by Kurita Water Industries, Ltd.
Filling resin in the desalination chamber of the continuous electric deionizer:
Anion exchange resin: "Nano Saver" manufactured by Kurita Water Industries, Ltd.
(Platinum nanocolloid carrier anion exchange resin) 10L
Cation exchange resin: "KR-UC1" manufactured by Kurita Water Industries, Ltd. 10L

The nitrogen gas flow rate is constant at 10 NL / min, the hydrogen gas flow rate is 0.1 NL / min, the oxygen gas flow rate is 0.5 NL / min, and hydrogen gas and oxygen gas are supplied for 30 seconds and oxygen gas for 60 seconds. The supply was switched alternately.

As a result, the TOC concentration of the treated water of the continuous electrodeionization device was 1 ppb or less, and the TOC could be highly decomposed and removed by continuous operation.

[Comparative Example 1]
Raw water is treated using a low-pressure ultraviolet lamp device (“AZ-26” manufactured by Nippon Photo Science Co., Ltd.), and further, a mixed resin of an ion exchange resin column (“KR-UA1” and “KR-UC1” manufactured by Kurita Kogyo Co., Ltd.). ) When the treatment was carried out, the TOC concentration of the treated water was 3 ppb, and since urea was the main component, it was not decomposed at all.

[Comparative Example 2]
Raw water was treated by the method described in Patent Document 1. That is, instead of the continuous electrodeionization device, a catalyst column filled with "Nano Saver" (platinum nanocolloid carrier anion exchange resin) manufactured by Kurita Kogyo Co., Ltd. is used, and an ion exchange resin column (Kurita Kogyo Co., Ltd.) is used in the subsequent stage. ) Made "KR-UA1" and "KR-UC1" mixed resin) was installed.
As a result, the TOC concentration of the treated water of the ion exchange resin column was 1 ppb or less, but when the catalyst column was switched from hydrogen treatment to oxygen treatment, a pressure fluctuation of about 10 kPa occurred and continuous treatment could not be performed. Further, the amount of the ion exchange resin adsorbed broke in about 20 days, and the resin exchange was required, so that continuous treatment could not be performed.

1 Gas dissolution film module 2 Continuous electric deionizer 10 Ion exchanger 11 Anode 12 Cathode 13 Anion exchange film 14 Cation exchange film 15 Concentration chamber 16 Desalting chamber 17 Anode chamber 18 Cathode chamber

Claims (4)

A TOC removing device having a continuous electric deionizing device including a catalyst having TOC resolution in a desalting chamber.
A gas dissolving means for dissolving hydrogen gas or oxygen gas in TOC-containing water,
A means for alternately introducing TOC-containing water in which hydrogen gas is dissolved and TOC-containing water in which oxygen gas is dissolved into the desalting chamber of the continuous electric deionizer by the gas dissolving means.
Have,
An oxygen gas feeding means that feeds an oxygen gas generated at the anode of the continuous electric deionizing device to the gas dissolving means as an oxygen gas that dissolves the TOC-containing water, and / or the continuous electric deionizing device. A TOC removing device comprising a hydrogen gas feeding means for feeding the hydrogen gas generated at the cathode of the gas to the gas dissolving means as a hydrogen gas for dissolving the hydrogen gas in the TOC-containing water . The gas dissolving means is provided in the gas dissolving film module provided in front of the continuous electric deionizing device, the hydrogen gas supplying means for supplying hydrogen gas to the gas phase chamber of the gas dissolving film module, and the gas phase chamber. The TOC-containing water is supplied to the oxygen gas supply means for supplying the oxygen gas, the switching means for alternately switching the gas supply by the hydrogen gas supply means and the oxygen gas supply means, and the liquid phase chamber of the gas dissolution film module. The TOC removing device according to claim 1 , further comprising means, wherein the gas-dissolved TOC-containing water flowing out of the liquid phase chamber is introduced into the desalting chamber of the continuous electric deionizing device. The TOC removing device according to claim 1 or 2 , wherein the catalyst having a TOC resolution is made of fine particles of a platinum group metal and is supported on an ion exchange resin. One of claims 1 to 3 , wherein the desalting chamber of the continuous electrodeionizer is filled with a cation exchange resin and an anion exchange resin carrying a metal having TOC resolution. The TOC removing device according to item 1.

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