JPH10277572A - Removal of organic matter in water - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently operate an org. matter decomposing means and to efficiently remove org. matter by properly controlling an org. matter removing means used in the removal of org. matter when org. matter in org. matter- containing water is removed. SOLUTION: Treated water of an org. matter decomposing means 32 is passed through an ion exchange means 38 using at least a union exchange resin and the concn. of org. matter in the treated water of the ion exchange means 38 is measured by an org. matter concn. measuring means 40 and, on the basis of the concn. value of the org. matter measured by the org. matter concn. measuring means 40, the loading of an oxidizing agent to water to be treated in the org. matter decomposing means 32 is controlled. As the org. matter decomposing means 32, for example, an org. matter decomposing means decomposing org. matter in water to be treated by adding ozone to water to be treated under an alkaline condition can be employed and, when this org. decomposing means is used, as the above mentioned control, the loading of ozone to water to be treated in the org. mater decomposing means is controlled.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for removing organic matter in organic matter-containing water, and more particularly, to an efficient operation of an organic matter decomposition means by appropriately controlling an organic matter removing means used for removing organic matter. The present invention relates to a method for efficiently removing organic matter. The organic matter removing method of the present invention, for example,
Ultrapure water used for cleaning silicon wafers in the semiconductor industry, make-up water for condensate from thermal power plants and nuclear power plants,
In the production process of pure water or ultrapure water used in the pharmaceutical manufacturing industry, etc., it is suitably used as a route for removing organic substances in the treated water containing organic substances (for example, a wastewater recovery system of an ultrapure water production apparatus). . Note that, in this specification, high-purity water, which is generally described in terms of pure water, ultrapure water, and the like, which are not necessarily clearly defined, is collectively referred to as “ultrapure water”.

[0002]

2. Description of the Related Art As shown in FIG. 11, an apparatus for producing ultrapure water used for cleaning a silicon wafer or the like generally includes a primary pure water system 2, a secondary pure water system (subsystem) 4, and a wastewater recovery system. A pure water drainage recovery system 6 is provided. The primary pure water system 2 includes, for example, an activated carbon filtration device, an ion exchange device using a cation exchange resin and an anion exchange resin such as a three-bed pure water production device and a mixed bed pure water production device, a vacuum deaeration tower, This is a route equipped with a reverse osmosis membrane device and the like. After a part of suspended substances and organic substances contained in raw water such as city water and industrial water are removed by a pretreatment system (not shown), the treated water 8
Is supplied to the primary pure water system 2.

The secondary pure water system 4 includes, for example, an ultraviolet oxidation device,
This is a path provided with a cartridge polisher, an ultrafiltration membrane device, and the like. The treated water 3 (primary pure water) of the primary pure water system 2 is supplied to the secondary pure water system 4 via the pure water storage tank 10. Part of the ultrapure water 12 obtained in the secondary pure water system 4 is sent to a use place 14 for use, and the remainder is circulated to a pure water storage tank 10.
The pure water wastewater recovery system 6 is a path provided with, for example, an activated carbon filtration device, an ion exchange device, an ultraviolet oxidation device, and the like, and the wastewater 1 generated by using ultrapure water at the use location 14.
6 is performed. The treated water 18 of the pure water wastewater recovery system 6 is
It is returned to the primary pure water system 2 and reused.

Further, in a general ultrapure water producing apparatus, as a wastewater recovery system for treating the ultrapure water wastewater 16 discharged from the place of use 14, the pure water is returned to the primary pure water system after being appropriately treated. Depending on the cleanliness of the wastewater, a route to return directly to the primary pure water system without any treatment, or a route to be used as miscellaneous water after appropriate treatment (drainage for miscellaneous water) (Recovery system), and a route (wastewater treatment system) for discharging after appropriate treatment.

In this case, in the above-mentioned pure water waste water recovery system, miscellaneous water waste water recovery system, and waste water treatment system, organic substances contained in waste water from the place of use are usually removed.
Conventionally, as a means for removing organic substances, hydrogen peroxide is added to water to be treated (drainage generated by using ultrapure water), and ultraviolet light is applied to the water to be treated with hydrogen peroxide. Organic substance decomposing means for decomposing organic substances contained in the water to be treated, and adding ozone to the water to be treated and decomposing the organic substances contained in the water to be treated by irradiating the water to which the ozone is added with ultraviolet rays. Organic matter decomposition means are known. In these means, the organic substance is oxidatively decomposed by a reaction between the organic substance and a hydroxyl radical generated by a reaction between ozone or hydrogen peroxide and ultraviolet rays.

[0006]

As described above, as a means for removing organic substances contained in organic substance-containing water, conventionally, ozone or hydrogen peroxide is added to water to be treated, and the ozone or hydrogen peroxide is added to the water. A method of irradiating the added water to be treated with ultraviolet rays is known.

Further, the present inventors have proposed a method of treating organic-containing water by using an organic-substance decomposing means for decomposing organic substances contained in the treated water by adding ozone to the treated water under alkaline conditions. It has been found that organic substances contained in organic substance-containing water can be efficiently removed without performing ultraviolet irradiation. In this means, an organic substance is oxidatively decomposed by a reaction between an organic substance and a hydroxy radical generated by a reaction between ozone and an alkali.

[0008] Further, as means for removing organic substances contained in the organic substance-containing water, there are other methods for decomposing organic substances contained in the treated water by adding ozone to the treated water under neutral or acidic conditions. Means, an organic matter decomposing means for decomposing organic substances contained in the water to be treated by adding ozone and hydrogen peroxide to the water to be treated, and
Organic substances contained in the water to be treated are decomposed by adding persulfuric acid and / or persulfate as an oxidizing agent to the water to be treated and subjecting the water to which the persulfuric acid and / or persulfate is added to heat treatment. Organic matter decomposing means (Japanese Unexamined Patent Publication No. 8-173)
No. 978).

By the way, in the above-mentioned six kinds of organic substance decomposition means, the amount of ozone added to the water to be treated,
The amount of ultraviolet irradiation to the water to be treated, the amount of hydrogen peroxide added to the water to be treated, and the amount of persulfuric acid and / or persulfate added to the water to be treated (hereinafter, these may be collectively referred to as an oxidizing agent addition amount, etc. ) Is important for efficient operation of the organic matter decomposition means and efficient removal of organic matter.

In this case, as a method for controlling the amount of the oxidizing agent added to the organic substance decomposing means, the TOC concentration in the water to be treated by the organic substance decomposing means is measured on the upstream side of the organic substance decomposing means.
In general, a method of controlling the amount of the oxidizing agent added in the organic matter decomposing means based on the TOC concentration is used. However, in this method, since the quality of the treated water of the organic substance decomposing means is not reflected in the above control, it is difficult to appropriately control the organic substance decomposing means due to, for example, an excessive or insufficient amount of the oxidizing agent added.

As a method for controlling the amount of the oxidizing agent added in the organic substance decomposing means, the TOC concentration in the treated water of the organic substance decomposing means is measured downstream of the organic substance decomposing means.
A method of controlling the amount of the oxidizing agent added in the organic matter decomposing means based on the OC concentration is also conceivable. However, in this method, when the organic substance is not decomposed into carbon dioxide by the organic substance decomposing means and is decomposed only into an organic acid which is an intermediate product, the organic acid is measured as a TOC component. It is difficult to properly control the organic matter decomposition means. In addition, when the organic acid is measured as the TOC component, the appropriate control of the organic substance decomposing means cannot be performed because, when the organic substance is decomposed into the organic acid in the organic substance decomposing means, the organic acid is usually located on the downstream side of the organic substance decomposing means. Since it is adsorbed and removed by the anion exchange resin used in the ion-exchange type pure water equipment that exists in the above, it is sufficient to decompose the organic matter into the organic acid in the organic matter decomposing means. This is because the cost is high and it is uneconomical.

The present invention has been made in view of the above circumstances, and in the above-mentioned six kinds of organic substance decomposing means, by appropriately controlling the amount of the oxidizing agent and the like, efficient operation of the organic substance decomposing means, It is an object of the present invention to provide a method for removing organic substances in water that can perform efficient removal.

[0013]

Means for Solving the Problems The present inventors have conducted various studies to achieve the above object, and as a result, when decomposing organic substances in organic substance-containing water using the above-mentioned six kinds of organic substance decomposing means, After passing the treated water of the organic matter decomposing means through at least the ion exchange means using an anion exchange resin, the organic matter concentration in the treated water of the ion exchange means is measured by the organic matter concentration measuring means, and the organic matter concentration measuring means is used. It has been found that the above object can be effectively achieved by controlling the amount of the oxidizing agent added in the organic matter decomposition means based on the measured value of the organic matter concentration.

That is, in the case described above, even when the organic substance is not decomposed into carbon dioxide by the organic substance decomposing means but is decomposed only into an organic acid, the organic acid is converted into at least an ion using an anion exchange resin. It can be removed by exchange means. Therefore, in the organic substance concentration measurement means, it is possible to measure the concentration of organic substances for treatment water of the organic substance decomposing means after removal of the organic acid, an appropriate assessment of the concentration of organic substances in the treated water of the organic decomposition unit, i.e. CO ₂ by organic decomposition means It is possible to evaluate the true concentration of the residual organic matter which was not decomposed into organic acids as well as decomposed into organic acids. Therefore, by controlling the amount of the oxidizing agent added in the organic matter decomposing means based on the value of the organic matter concentration, it is possible to appropriately control the amount of the oxidizing agent added, and as a result, the efficient operation of the organic matter decomposing means and the organic matter Can be efficiently removed.

Accordingly, the present invention provides the following first inventions:
A sixth invention is provided. In decomposing the organic matter in the organic matter-containing water using an organic matter decomposing means that decomposes organic matter contained in the water to be treated by adding ozone to the water to be treated, the treated water of the organic matter decomposing means is converted into at least an anion. Water is passed through an ion exchange means using an exchange resin, and the organic matter concentration in the treated water of the ion exchange means is measured by the organic matter concentration measurement means, and the organic matter concentration is measured based on the value of the organic matter concentration measured by the organic matter concentration measurement means. A method for removing organic matter in water, comprising controlling the amount of ozone added to the water to be treated in the decomposition means.

In the second invention, the organic matter in the water containing organic substances is decomposed by adding ozone to the water to be treated under alkaline conditions to decompose organic substances contained in the water to be treated. The treated water is passed through at least an ion exchange means using an anion exchange resin, and the organic matter concentration in the treated water of the ion exchange means is measured by the organic matter concentration measuring means, and the organic matter concentration measured by the organic matter concentration measuring means is measured. Controlling the amount of ozone added to the water to be treated in the organic substance decomposing means based on the value of the organic substance decomposing means.

Third invention Ozone is added to the water to be treated, and the water to be treated with the ozone is irradiated with ultraviolet rays to decompose the organic matter contained in the water to be treated by using an organic matter decomposing means. In decomposing the organic matter, the treated water of the organic matter decomposing means is passed through at least an ion exchange means using an anion exchange resin, and the organic matter concentration in the treated water of the ion exchange means is measured by an organic matter concentration measuring means, A method for removing organic matter in water, comprising controlling the amount of ozone added to the water to be treated and / or the amount of ultraviolet irradiation in the organic matter decomposing means based on the value of the organic matter concentration measured by the organic matter concentration measuring means.

Fourth Invention In decomposing organic substances in water containing organic substances by using an organic substance decomposition means for decomposing organic substances contained in the water to be treated by adding ozone and hydrogen peroxide to the water to be treated,
The treated water of the organic matter decomposing means is passed through at least an ion exchange means using an anion exchange resin, and the organic matter concentration in the treated water of the ion exchange means is measured by an organic matter concentration measuring means. A method for removing organic substances in water, comprising controlling the amount of ozone and / or hydrogen peroxide added to the water to be treated in the organic substance decomposition means based on the measured value of the organic substance concentration.

Fifth invention Hydrogen peroxide is added to the water to be treated, and ultraviolet light is applied to the water to which the hydrogen peroxide has been added to thereby decompose organic substances contained in the water to be treated. In decomposing the organic matter in the organic matter-containing water, the treated water of the organic matter decomposing means is passed through at least an ion exchange means using an anion exchange resin, and the organic matter concentration in the treated water of the ion exchange means is measured by an organic matter concentration measuring means. Measuring and controlling the amount of hydrogen peroxide added to the water to be treated and / or the amount of ultraviolet irradiation in the organic matter decomposing means based on the value of the organic matter concentration measured by the organic matter concentration measuring means. Organic matter removal method.

Sixth invention Persulfuric acid and / or persulfate are added to the water to be treated as an oxidizing agent, and the water to which the persulfuric acid and / or persulfate is added is subjected to heat treatment, whereby the water to be treated is treated with water. In decomposing the organic matter in the organic matter-containing water using an organic matter decomposing means for decomposing the organic matter contained, the treated water of the organic matter decomposing means is passed through at least an ion exchange means using an anion exchange resin. The organic matter concentration in the treated water is measured by the organic matter concentration measuring means, and the persulfuric acid and / or persulfate is added to the water to be treated in the organic matter decomposing means based on the value of the organic matter concentration measured by the organic matter concentration measuring means. A method for removing organic substances in water, comprising controlling the amount of addition.

Hereinafter, the present invention will be described in more detail. First, the organic substance removing means used in the present invention will be described. In the present invention, the following (a) to (f) are used as the organic matter decomposing means. (A) Organic substance decomposing means for decomposing organic substances contained in water to be treated by adding ozone to the water to be treated (first invention). (B) Organic substance decomposing means for decomposing organic substances contained in the water to be treated by adding ozone to the water to be treated under alkaline conditions (second invention). (C) an organic substance decomposing means for adding ozone to the water to be treated and irradiating the water to be treated with ozone with ultraviolet rays to decompose organic substances contained in the water to be treated (third substance);
invention). (D) Organic substance decomposing means for decomposing organic substances contained in the water to be treated by adding ozone and hydrogen peroxide to the water to be treated (a fourth invention). (E) An organic matter decomposing means for adding hydrogen peroxide to the water to be treated and irradiating the water to be treated with the hydrogen peroxide with ultraviolet rays to decompose organic substances contained in the water to be treated (fifth invention). (F) Organic substances contained in the water to be treated by adding persulfuric acid and / or persulfate as an oxidizing agent to the water to be treated and subjecting the water to which the persulfuric acid and / or persulfate is added to heat treatment. Organic substance decomposing means for decomposing (6th invention).

As the organic substance decomposing means (a), a means having an ozone supply mechanism for adding ozone to the water to be treated can be used.

The constitution of the organic substance decomposing means (b) is not limited, but preferably has one of the following conditions, especially both. Ozone is added to the water to be treated by gas-liquid stirring and mixing means. Ozone is added to the water to be treated under alkaline conditions where the pH of the water to be treated is 9.7 or more.

That is, when ozone is added to the water to be treated, ozone has low solubility in water, so that it is not sufficiently dissolved in water by bubbling using a diffuser plate, and the oxidative decomposition reaction of organic substances is efficiently performed. Although it is difficult, ozone can be sufficiently dissolved in the water to be treated by using the gas-liquid stirring and mixing means, and the oxidative decomposition reaction of organic substances is efficiently performed. Therefore, it is preferable that the organic matter decomposing means (b) has the following conditions.

Here, the gas-liquid stirring and mixing means refers to a means for mixing a gas and a liquid while stirring to dissolve the gas in the liquid. As a method for dissolving ozone using such a means, for example, water to be treated and ozone are introduced into the suction side of a pump equipped with a rotating blade, and the water to be treated and ozone are stirred and mixed by rotation of the rotating blade. Ozone is dissolved in the water to be treated by stirring and mixing, and the water to be treated in which the ozone is dissolved is sent to the treatment system through a pipe connected to the discharge side of the pump (ozone dissolving pump). Then, a pressurized water flow is supplied by an ejector or the like, and the water to be treated and ozone are stirred and mixed by the movement of the water flow to dissolve ozone in the water to be treated. Further, a line mixer having a stirring mechanism provided with a rotating blade inside a sealed container formed with a sealed blade in the middle of the pipe can also be used. In addition, it is needless to say that the above-mentioned conditions are preferably satisfied also in the organic substance decomposing means (a).

FIG. 10 shows a case where a plurality of waters (TOC concentration: 2000 ppb) containing isopropyl alcohol as an organic substance are prepared, each is adjusted to various different pHs by adding an alkali, and 9.6 ppm of ozone is added. This shows how the degree of oxidative decomposition of organic matter changes depending on the initial pH value. TOC on the vertical axis of the graph indicates the residual TOC after 10 minutes from the ozone reaction. According to the figure, the pH is 9.7 or higher, especially pH 9.7 to 11.1.
It can be seen that the decomposition rate of organic substances is high in the range of 0, especially in the range of pH 10.0 to 10.5. Therefore, it is preferable that the organic matter decomposing means (b) has the following conditions.

In the organic substance decomposing means (b), the pH of the water to be treated may be adjusted before dissolving ozone in the water to be treated. May be adjusted, and the pH adjustment of the water to be treated and the ozone dissolution in the water to be treated may be performed simultaneously. When ozone is added to the water to be treated under alkaline conditions, the oxidative decomposition reaction of the organic matter in the water to be treated starts immediately. However, by heating the water to be treated, the oxidative decomposition rate of the organic matter can be increased.

As the organic substance decomposing means (c), a means having an ozone supply mechanism for adding ozone to the water to be treated and an ultraviolet irradiation mechanism for irradiating ultraviolet rays to the water to be treated with ozone may be used. it can. In this case, the ultraviolet irradiation mechanism is not particularly limited, and any of those equipped with a high-pressure ultraviolet lamp and those equipped with a low-pressure ultraviolet lamp can be used, but it mainly generates ultraviolet light having a wavelength around 365 nm. (It is needless to say that the high-pressure ultraviolet lamp has a main wavelength of 365 nm, and also generates ultraviolet light of wavelengths of 254 nm and 185 nm.) Is appropriate.

As the organic substance decomposing means (d), a means provided with a hydrogen peroxide addition mechanism for adding hydrogen peroxide to the water to be treated and an ozone supply mechanism for adding ozone to the water to be treated may be used. it can.

The organic matter decomposing means (e) includes a hydrogen peroxide addition mechanism for adding hydrogen peroxide to the water to be treated, and an ultraviolet irradiation mechanism for irradiating ultraviolet rays to the water to be treated with hydrogen peroxide added. Things can be used. In this case, it is appropriate to use an ultraviolet irradiation mechanism provided with a high-pressure ultraviolet lamp that mainly generates ultraviolet light having a wavelength of around 365 nm, as in the case of the organic substance decomposition means (c) described above.

The organic matter decomposing means (f) includes an oxidizing agent adding mechanism for adding persulfuric acid (H ₂ S ₂ O ₈ ) and / or persulfate to the water to be treated, and a persulfuric acid and / or persulfate. The one provided with a heat treatment mechanism for heating the added water to be treated can be used. In this case, examples of the persulfate include sodium peroxydisulfate (Na ₂ S ₂ O ₈ ), potassium peroxydisulfate (K ₂ S ₂ O ₈ ), ammonium peroxydisulfate ((NH ₄ ) ₂ S ₂ O ₈ ) and the like. Can be used. Further, the heating temperature of the water to be treated in the heat treatment mechanism is preferably 90 ° C. or more, particularly 110 to 150 ° C., and the heat treatment time is suitably 1 to 15 minutes.

In the first to sixth inventions, after treating the organic substance-containing water with the organic substance decomposing means (a) to (f), the treated water is converted into at least an ion exchange means using an anion exchange resin. Water. In this case, as the ion exchange means, for example, an ion exchange column in which an ion exchange resin is filled in a column, an electrodialysis device using an ion exchange resin (described later), or the like can be used.

As the anion exchange resin, either a strongly basic anion exchange resin or a weakly basic anion exchange resin can be used, and the form of the anion exchange resin may be any one such as granular or fibrous. be able to. As an anion exchange resin, specifically, Amberlite IRA-402, I
RA-402BL, IRA-400 (all of which are strongly basic anion exchange resins), IRA-68, and IRA-400
94S (all of these are weakly basic anion exchange resins)
Etc. can be used. Furthermore, the ionic form of the anion exchange resin used may be any as long as it can remove the organic acid generated by the decomposition of the organic substance, in short.
The OH form or the salt form (Cl form, HCO ₃ form, etc.) can be used, but it is usually preferable to use an OH form anion exchange resin.

The above-mentioned ion exchange means only needs to use at least an anion exchange resin. Therefore, the anion exchange resin may be used alone or a combination of an anion exchange resin and a cation exchange resin may be used. Good. However, when an OH type anion exchange resin is used as the anion exchange resin, when the treated water containing organic substance is passed through the ion exchange means using the OH type anion exchange resin alone, The treated water becomes alkaline, and it may be difficult for the organic matter concentration measuring means to measure the organic matter concentration of the treated water of the ion exchange means. Therefore,
When using an OH type anion exchange resin as the ion exchange means, use a combination of an OH type anion exchange resin and an H type cation exchange resin, and make the treated water of the ion exchange means near neutral. Is preferred.

In this case, the type of the cation exchange resin is not limited, and any of a strongly acidic cation exchange resin and a weakly acidic cation exchange resin can be used. You can choose one. Specific examples of the cation exchange resin include, for example, Amberlite (registered trademark, hereinafter the same) IR-120B, IR-120B
124, 200CT, Diaion (registered trademark, the same applies hereinafter) SK1B, PK216 and the like can be used.

In the first to sixth inventions, the concentration of the organic substance in the treated water of the ion exchange means is measured by the organic substance concentration measuring means. In this case, a typical example of the organic substance concentration measuring means is a TOC meter.
Various TOC meters can be used as the TOC meter. Then, based on the value of the organic matter concentration measured by the organic matter concentration measuring means, in the first invention or the second invention, the amount of ozone added to the water to be treated in the organic matter decomposing means,
In the invention, the amount of ozone added to the water to be treated and / or the amount of ultraviolet irradiation in the organic matter decomposition means, the amount of ozone and / or hydrogen peroxide added to the water to be treated in the organic matter decomposition means in the fourth invention, the organic matter in the fifth invention The amount of hydrogen peroxide added to the water to be treated in the decomposition means and / or the amount of ultraviolet irradiation,
In the present invention, the amount of persulfuric acid and / or persulfate added to the water to be treated in the organic matter decomposition means is controlled.

In this case, as the control method, for example, a signal corresponding to the organic substance concentration is sent from the organic substance concentration measuring means to the control section of the organic substance decomposing means, and the control section of the organic substance decomposing means controls the oxidizing agent based on the signal. A method of controlling the amount of addition and the like can be mentioned. In addition, the control of the ozone addition amount is as follows.
For example, it can be performed by adjusting the flow rate of the ozone-containing gas introduced into the water to be treated, or adjusting the ozone concentration in the ozone-containing gas. The control of the amount of ultraviolet irradiation can be performed by, for example, turning on / off a part of the ultraviolet lamp, adjusting the voltage applied to the ultraviolet lamp, and the like.

In the present invention, the organic matter decomposing means (a)
An oxidizing agent for decomposing an oxidizing agent such as ozone, hydrogen peroxide, persulfuric acid, and persulfate remaining in the treated water of the organic matter decomposing means between (f) and at least an ion exchange means using an anion exchange resin; Decomposition means can be provided. This can prevent the oxidizing agent remaining in the treated water of the organic matter decomposing means from adversely affecting the subsequent ion exchange means and the like. As the oxidizing agent decomposing means, for example, means for flowing the water to be treated through a packed tower filled with activated carbon, a platinum-based catalyst, or a palladium-based catalyst to reductively decompose the oxidizing agent, and injecting the reducing agent into the treated water For reductive decomposition of the oxidizing agent. The oxidizing agent decomposing means is preferably installed immediately after the organic substance decomposing means in order to prevent the oxidizing agent from adversely affecting the subsequent device.

In the present invention, the organic matter decomposing means is downstream and as close as possible to the organic matter decomposing means, preferably immediately after the organic matter decomposing means, or immediately after the oxidizing agent decomposing means when the oxidizing agent decomposing means is provided. At least, the treated water of the organic substance decomposing means is passed through at least an ion exchange means using an anion exchange resin, and measuring the organic substance concentration in the treated water appropriately controls the oxidizing agent addition amount and the like in the organic substance decomposing means. It is preferred in that respect.

In the apparatus for producing ultrapure water as shown in FIG. 11, an activated carbon filter as an oxidizing agent decomposing means and a two-bed as an ion exchange means using an anion exchange resin are used in the primary pure water system. Usually, a three-tower type pure water production device or a mixed-bed type pure water production device is installed. Therefore, when the organic matter decomposing means is installed in the pure water wastewater recovery system, if the organic matter concentration in the water is measured by the organic matter concentration measuring means at the subsequent stage of the primary pure water based activated carbon filtration device and the pure water production device,
Since the organic substance concentration can be measured in the treated water of the organic substance decomposing means after removing the organic acid, the organic substance concentration in the treated water of the organic substance decomposing means should be able to be appropriately evaluated.

However, in such a case, it takes time for the treated water that has exited the organic substance decomposing means to reach the position of the organic substance concentration measuring means. Therefore, control of the organic substance decomposing means is performed based on the measurement result. If so, there is a possibility that a time lag occurs and appropriate control cannot be performed. In addition, since the water for measuring the organic matter concentration by this method is a mixture of raw water of primary pure water and treated water of a wastewater recovery system for pure water, it is affected by the TOC concentration of raw water of primary pure water. The TOC concentration of the treated water of the organic matter decomposing means cannot be correctly evaluated. However, in such an apparatus in which the activated carbon filtration device and the pure water production device are present on the downstream side, the treated water of the organic matter decomposing means is bothered immediately after the organic matter decomposing means only for measuring the organic matter concentration in the treated water of the organic matter decomposing means. It is uneconomical in terms of equipment to install an oxidizing agent decomposing means or an ion exchanging means using an anion exchange resin for passing the whole amount of water.

Accordingly, in the present invention, at least an ion-exchange means using an anion-exchange resin through which all of the water treated by the organic matter decomposition means flows downstream of the organic matter decomposition means, and an oxidizing agent decomposition means as required. May be installed, the organic matter concentration in the treated water of the ion exchange means may be measured, but for the organic matter concentration measurement in which a part of the treated water of the organic matter decomposing means is diverted, preferably immediately downstream of the organic matter decomposing means. Along with providing a branch flow path, at least an ion exchange means using an anion exchange resin in this branch flow path, and an oxidizing agent decomposing means if necessary, the organic substance decomposition means divided into the branch flow path After passing the treated water through the ion exchange means, the organic matter concentration in the treated water of the ion exchange means is measured by the organic matter concentration measuring means, so that the organic matter decomposition after removing the organic acid is performed. It may be measured a concentration of organic substances on stage of the treated water. In addition, the amount of water diverted to the branch channel can be set as appropriate, but usually, it may be as small as necessary for measuring the concentration of organic substances.

When measuring the organic matter concentration in the treated water of the organic matter decomposing means by providing the branch flow path as described above, at least the ion exchange means using an anion exchange resin includes:
It is appropriate to use an electrodialysis device using an anion exchange resin, particularly an electrodialysis device using an anion exchange resin and a cation exchange resin. The anion exchange resin and the cation exchange resin used in the electrodialyzer are as described above.

Since the electrodialysis apparatus can be operated continuously without regenerating the ion exchange resin, if the electrodialysis apparatus is used, the concentration of organic substances in the treated water of the organic substance decomposition means can be continuously and without interruption. Can be measured. In this case, as the electrodialysis apparatus, for example, a plurality of cation exchange membranes and anion exchange membranes are alternately arranged between the opposed electrode pairs, and a desalting chamber and a concentrating chamber are formed alternately. A desalination chamber that produces salt water and filled with an ion exchange resin can be used. When the desalting chamber is filled with both the anion exchange resin and the cation exchange resin, the method of filling is not limited, and for example, both ion exchange resins may be mixed and filled. The layers may be laminated and filled without mixing.

When the concentration of organic substances in the treated water of the organic substance decomposition means is measured by providing a branch flow path, the organic substance concentration measuring means is particularly preferably an on-line measurement for continuously measuring the organic substance concentration of flowing water. Is a type of TOC meter that uses only a small amount of water for measurement.
By using such a TOC meter, the concentration of organic substances in the treated water of the organic substance decomposing means can be continuously measured without interruption, and the amount of water introduced into the TOC meter can be reduced. Specific examples of the TOC meter are SEIVERS-810 manufactured by SEIVERS and A-10 manufactured by ANATEL.
0, A-1000 and the like. In these TOC analyzers, an oxidizing agent such as persulfuric acid is added to the sample water, and furthermore, the organic matter in the sample water is completely decomposed into carbon dioxide by irradiating ultraviolet rays, and the carbon dioxide raises the conductivity of the sample water. Is detected to measure the TOC concentration. It should be noted that the water used for the measurement by the TOC meter contains an oxidizing agent such as persulfuric acid, and is usually discarded.

The organic matter removing method of the present invention is not particularly limited. For example, a route of returning to the primary pure water system after performing an appropriate treatment in the above-mentioned waste water recovery system of the ultrapure water producing apparatus ( Wastewater recovery system for pure water), a route to be used as miscellaneous water after appropriate treatment (drainage collection system for miscellaneous water),
It can be used for a route (wastewater treatment system) for discharging after appropriate treatment.

[0047]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a flow chart showing an embodiment of an organic substance removing apparatus used for carrying out the method of the present invention.
In the apparatus of FIG. 1, reference numeral 32 denotes an organic matter decomposing means, 33 denotes a main flow path through which most of the treated water of the organic matter decomposing means 32 flows,
Reference numeral 4 denotes a branch flow path for measuring an organic substance, which is connected to the main flow path 33 immediately after the organic substance decomposition means 32 and in which a part of the water treated by the organic substance decomposition means 32 flows. In the branch flow path 34, an activated carbon filtration device 36 is sequentially provided from the upstream side to the downstream side.
(Oxidizing agent decomposing means), an electrodialyzer 38 using an anion exchange resin and a cation exchange resin (at least an ion exchange means using an anion exchange resin), and a TOC meter 40 capable of online measurement (organic substance concentration measuring means) ) Is installed, and a part of the treated water of the organic matter decomposing means 32 diverted to the branch flow path 34 flows into the activated carbon filtration device 36, the electrodialysis device 38 and the TOC meter 40 in order, and is included in the treated water of the electrodialysis device 38. The organic substance concentration is measured by the TOC meter 40. Further, the organic matter decomposing means 32 and the TOC meter 40 are instrumentally connected, and a signal corresponding to the organic matter concentration measured by the TOC meter 40 is sent from the TOC meter 40 to the organic matter decomposing means 32, and the signal The amount of the oxidizing agent added to the organic matter decomposing means 32 is controlled accordingly. Further, in the figure, reference numeral 42 denotes a tank connected to the main flow path 33 and into which the treated water of the organic matter decomposing means 32 is introduced. Since a small amount of water is used in the measurement by the TOC meter 40, only a part of the water treated by the electrodialyzer 38 is used in the TOC meter 4.
0, mostly through the return channel 44
Sent to 2. In addition, instead of the electrodialysis device 38, O
A cartridge type pure water production apparatus in which a mixed resin of an H-type anion exchange resin and an H-type cation exchange resin is filled in a cylinder may be used.

In the organic substance removing apparatus of this embodiment, when the above-mentioned (a) is used as the organic substance decomposing means 32, the organic substance decomposing means (a) may have a structure shown in FIG. 2, for example. . In FIG. 2, reference numeral 45 denotes a line through which water to be treated flows, and a reaction tank 46 for adding ozone to the water to be treated is interposed in the line 45. An ozone supply mechanism 48 is connected to the reaction tank 46. ing. When the organic matter decomposition means 32 shown in FIG. 2 is used, the amount of ozone added to the water to be treated from the ozone supply mechanism 48 is controlled based on a signal from the TOC meter 40.

In the organic substance removing apparatus of this embodiment, when the organic substance decomposing means (b) is used as the organic substance decomposing means 32, the organic substance decomposing means (b) may have, for example, the structure shown in FIG. . In FIG. 3, reference numeral 50 denotes a line through which the water to be treated flows. The line 50 is connected to an alkali injection device 52 and an ozone supply mechanism 54. A pH measuring section (not shown) is provided slightly behind the connecting section 58 between the injection pipe 56 and the line 50 of the alkali injecting apparatus 52, and the pH measuring section controls the pH of the water to be treated.
H is measured, and the measurement result is output as an electric signal to the alkali injecting device 52, based on which the amount of alkali injected into the water to be treated is automatically controlled.

As the ozone supply mechanism 54, an ozone generator having an ozone generating mechanism or an ozone tank filled with an ozone-containing gas produced by the ozone generator is used. A gas-liquid stirring and mixing device 62 (for example, a line mixer or an ozone dissolving pump) is connected to the supply pipe 60 of the ozone supply mechanism 54, and the gas-liquid stirring and mixing device 62 is connected to the line 50. A predetermined length of the line 50 on the outlet side of the gas-liquid stirring and mixing device 62 is configured as a reaction tube portion 66 in which an oxidative decomposition reaction of an organic substance is performed.

In the organic substance decomposing means (b) of this embodiment, first,
Alkali is injected into the water to be treated flowing through the line 50 from the alkali injecting device 52 so that the pH of the water to be treated is 9.7 or more
Preferably, it is adjusted to 9.7 to 11.0. Next, ozone is supplied to the water to be treated from the ozone supply mechanism 54, the ozone and the water to be treated are stirred and mixed by the gas-liquid stirring and mixing device 62, and most of the ozone is dissolved in the water to be treated. Here, the amount of ozone added to the water to be treated is 3 to 40 ppm,
Preferably it is adjusted to 7 to 30 ppm. In the to-be-treated water, the oxidative decomposition reaction of the organic matter rapidly proceeds in the reaction tube section 66. When the organic matter decomposing means 32 shown in FIG. 3 is used, the amount of ozone added to the water to be treated from the ozone supply mechanism 54 is controlled based on a signal from the TOC meter 40.

In the organic substance removing apparatus of this embodiment, when the organic substance decomposing means (c) is used as the organic substance decomposing means 32, for example, the organic substance decomposing means (c) having the structure shown in FIG. 4 can be used. . In FIG. 4, reference numeral 72 denotes an ultraviolet irradiation tank, 74 denotes a high-pressure ultraviolet lamp inserted into the ultraviolet irradiation tank 72 and mainly generates ultraviolet light having a wavelength of around 365 nm, 76 denotes a treated water inflow pipe connected to the ultraviolet irradiation tank 72, Reference numeral 86 denotes a gas-liquid stirring / mixing device (for example, a line mixer or an ozone dissolving pump) interposed in the treated water inflow pipe 76; 88, an ozone supply pipe connected to the gas-liquid stirring / mixing device 86; 3 shows a connected treated water outflow pipe. In the organic matter decomposing means (c) of this example,
An ozone supply mechanism 90 for adding ozone to the water to be treated flowing through the treated water inflow pipe 76 by the gas-liquid stirring and mixing device 86 and the ozone supply pipe 88 is configured.

In the organic substance decomposing means (c) of this embodiment, ozone is added to the water to be treated by the ozone supply mechanism 90, and the water to be treated with the added ozone is irradiated with an ultraviolet light from an ultraviolet irradiation tank 72 and a high-pressure ultraviolet lamp 74. Irradiation of ultraviolet rays by the irradiation mechanism decomposes organic substances contained in the water to be treated. When the organic matter decomposing means 32 shown in FIG. 4 is used, the amount of ozone added to the water to be treated by the ozone supply mechanism 90 based on the signal from the TOC meter 40 and / or
Alternatively, the amount of ultraviolet irradiation on the water to be treated in the ultraviolet irradiation mechanism is controlled. The apparatus of FIG. 4 can reduce the number of high-pressure ultraviolet lamps as compared with the apparatus of FIG. 6 described later.

In the organic substance removing apparatus of this embodiment, when the above-mentioned organic substance decomposing means (d) is used as the organic substance decomposing means 32, the organic substance decomposing means (d) having the structure shown in FIG. 5, for example, can be used. . In FIG. 5, reference numeral 45 denotes a line through which the water to be treated flows. The line 45 is connected to a hydrogen peroxide addition mechanism 47 for adding hydrogen peroxide to the water to be treated flowing through the line. Further, a reaction tank 46 for adding ozone to the water to be treated is interposed downstream of the connecting point of the hydrogen peroxide addition mechanism 47 in the line 45, and an ozone supply mechanism 48 is connected to the reaction tank 46. I have. When the organic matter decomposition means 32 shown in FIG.
The amount of hydrogen peroxide added to the water to be treated from the hydrogen peroxide addition mechanism 47 and / or the amount of ozone added to the water to be treated from the ozone supply mechanism 48 are controlled based on the signal from the total 40.

In the organic substance removing device of this embodiment, when the above-mentioned (e) is used as the organic substance decomposing means 32, the organic substance decomposing means (e) may have a structure shown in FIG. 6, for example. . In FIG. 6, reference numeral 72 denotes an ultraviolet irradiation tank, 74 denotes a high-pressure ultraviolet lamp inserted into the ultraviolet irradiation tank 72 and mainly generates ultraviolet light having a wavelength of around 365 nm, 76 denotes a treated water inflow pipe connected to the ultraviolet irradiation tank 72, Reference numeral 78 denotes a hydrogen peroxide addition mechanism for adding hydrogen peroxide to the water to be treated flowing through the treated water inflow pipe 76, and reference numeral 80 denotes a treated water outflow pipe connected to the ultraviolet irradiation tank 72.

In the organic substance decomposing means (e) of this embodiment, hydrogen peroxide is added to the water to be treated by the hydrogen peroxide adding mechanism 78, and the ultraviolet light irradiation tank 72 and the high-pressure ultraviolet ray are added to the water to which hydrogen peroxide is added. By irradiating ultraviolet rays by an ultraviolet irradiation mechanism including the lamp 74, organic substances contained in the water to be treated are decomposed. 6 is used as the organic matter decomposing means 32, the amount of hydrogen peroxide added to the water to be treated by the hydrogen peroxide addition mechanism 78 and / or the water to be treated in the ultraviolet irradiation mechanism based on the signal from the TOC meter 40. The amount of ultraviolet irradiation to the substrate is controlled.

In the organic substance removing apparatus of this embodiment, when the above-mentioned (f) is used as the organic substance decomposing means 32, the organic substance decomposing means (f) having the structure shown in FIG. 7, for example, can be used. . In FIG. 7, reference numeral 92 denotes a heat exchanger for heating, 93 denotes a thermal decomposition reactor, 94 denotes a heat exchanger for cooling, 96 denotes an oxidizing agent adding mechanism, and 97 denotes a neutralizing agent adding mechanism. In the organic matter decomposing means (f) of this example, after the water to be treated is heated by the heat exchanger 92 for heating, Na ₂ S _{2 is} used as an oxidizing agent.
O ₈ is added, and the organic matter is thermally decomposed in the thermal decomposition reactor 93. The treated water in the thermal decomposition reactor 93 is cooled in a cooling heat exchanger 94, and then NaOH for neutralization is added. When the organic matter decomposition means 32 shown in FIG.
Based on the signal from the C meter 40, the amount of the oxidizing agent added to the water to be treated by the oxidizing agent adding mechanism 96 is controlled.

Further, in the organic matter removing apparatus of this embodiment, the electrodialyzer 38 has a structure specifically shown in FIG. That is, an electrode pair 100 disposed opposite to both ends,
100, a plurality of cation exchange membranes 102 and anion exchange membranes 104 are alternately arranged.
A desalting chamber 106 and a concentrating chamber 108 are alternately formed between 2 and 104, the anion exchange resin and the cation exchange resin are mixed and filled in the desalination chamber 106, and the electrode 100 and the ion exchange membrane 102 are filled. , 104 is defined as an electrode chamber 110. In the electrodialysis apparatus 38 of this example, the desalination chamber 1
06 to be treated water 112 (treated water of activated carbon filtration device 36)
Is flowed downward and demineralized water 114 (processed water) is obtained from the desalination chamber 106, and the water to be treated 112 is flowed upward in the concentration chamber 108 to obtain concentrated water 116 from the concentration chamber 108.
The obtained desalinated water 114 is sent to the TOC meter 40 and
Used for measurement of C concentration. In addition, the electrodialysis device 3 of this example
8, a part of the concentrated water 116 is used as the electrode water 118. Further, in the electrodialysis apparatus 38 of the present example, the water to be treated is caused to flow into the concentration chamber 108, but the water flowing to the concentration chamber 108 may be other water.

FIG. 9 is a flow chart showing another embodiment of the organic matter removing apparatus used for carrying out the method of the present invention. In the apparatus shown in FIG. 9, reference numeral 130 denotes an organic matter decomposing means, and 132 denotes a flow path through which treated water of the organic matter decomposing means 130 flows. In the flow path 130, an activated carbon filtration device 134 (oxidizing agent decomposing means), a mixed bed type ion exchange column 136 using an OH type anion exchange resin and an H type cation exchange resin are sequentially provided from the upstream side to the downstream side. (At least an ion exchange means using an anion exchange resin) and a TOC meter 138 (organic matter concentration measuring means) are provided, and the total amount of the water treated by the organic matter decomposing means 130 is supplied to the activated carbon filtration device 134 and the ion exchange tower 13.
6 and the organic matter concentration in the treated water of the ion exchange tower 136 is measured by the TOC meter 138. Further, the organic matter decomposing means 130 and the TOC meter 138 are instrumentally connected, and a signal corresponding to the organic matter concentration measured by the TOC meter 138 is sent from the TOC meter 138 to the organic matter decomposing means 130, and the signal The amount of the oxidizing agent added to the organic matter decomposing means 130 is controlled accordingly. In the figure, reference numeral 140 denotes a tank connected to the channel 130 and into which the treated water of the ion exchange tower 136 is introduced. In addition, as the organic matter decomposing means 130, specifically, for example, those described above with reference to FIGS. 2 to 7 can be used.

[0060]

[Experimental example] The following experiment was conducted. Thereby, after passing the treated water of the organic matter decomposing means through the ion exchange means using the anion exchange resin, the concentration of the organic matter in the treated water of the ion exchange means is measured by the organic matter concentration measuring means, whereby the anion exchange is performed. It was confirmed that the concentration of organic substances other than the organic acid remaining in the treated water of the organic substance decomposing means after the organic acid was removed by the means could be appropriately evaluated.

The organic substance decomposing means shown in FIG. 3, FIG. 4 or FIG. 6 and the anion exchange means using a strong basic anion exchange resin (Amberlite IR-402BL) in OH form were connected in this order. The wastewater containing isopropyl alcohol was flowed through the experimental devices to treat the wastewater. Wastewater (raw water) having a TOC concentration of 1000 ppb was used.

In this case, in the experimental apparatus using the organic matter decomposing means (b) shown in FIG.
After adjusting the H to 10.3, ozone was added to the water to be treated by the gas-liquid stirring and mixing device 62 so that ozone dissolved in the water to be treated was 20 ppm. Note that an ozone dissolving pump was used as the gas-liquid stirring and mixing device 62.

In the experimental apparatus using the organic matter decomposing means (c) shown in FIG. 4, the amount of ozone added to the water to be treated is 15 p.
pm, the residence time of the water to be treated in the ultraviolet irradiation tank 72 is 40 minutes, and the amount of ultraviolet irradiation is 0.34 KW per m ³ of wastewater.
h. In the experimental apparatus using the organic matter decomposing means (e) shown in FIG. 6, the amount of hydrogen peroxide added to the water to be treated from the hydrogen peroxide addition mechanism 78 was set to 30 ppm, and the amount of hydrogen peroxide in the ultraviolet irradiation tank 72 was reduced. The residence time of the treated water was 1 hour, and the amount of ultraviolet irradiation was 1 KWh per 1 m ³ of the wastewater. In the organic substance decomposing means (c) and (e), a high-pressure ultraviolet lamp was used as the ultraviolet lamp.

Table 1 shows the measurement results of the TOC concentrations of the outlet water of the organic matter decomposing means and the outlet water of the anion exchange means. As shown in Table 1, the TOC concentration of the outlet water of the anion exchange means was determined by removing the organic acid, which is an intermediate product contained in the outlet water of the organic matter decomposition means, by the anion exchange means. It can be seen that the water is smaller than the outlet water of the decomposition means. Therefore, according to the present experiment, after passing the treated water of the organic matter decomposing means at least through the ion exchange means using an anion exchange resin, by measuring the organic matter concentration in the treated water of the ion exchange means, the intermediate product The organic matter concentration of the treated water of the organic matter decomposing means after removing an organic acid can be measured, and the oxidizing agent addition amount and the like can be measured by controlling the oxidizing agent addition amount and the like in the organic matter decomposing means based on the value of the organic matter concentration. It is clear that proper control is possible.

[0065]

[Table 1]

[0066]

According to the present invention, (a) to (d)
In the six kinds of organic substance decomposing means (f), the oxidizing agent addition amount and the like are appropriately controlled to efficiently operate the organic substance decomposing means,
It is possible to efficiently remove organic matter. Especially,
In the case where a branch channel for diverting a part of the treated water of the organic substance decomposing unit is provided, and an ion exchange unit using an anion exchange resin and an organic substance concentration measuring unit are provided in this branch channel, the ion There is an advantage that the exchange means can be small. Further, when an electrodialysis device is used as the ion exchange means, there is an advantage that the water to be treated can be continuously treated without regenerating the ion exchange resin.

[Brief description of the drawings]

FIG. 1 is a flowchart showing an embodiment of an organic matter removing apparatus according to the present invention.

FIG. 2 is a schematic view showing an example of an organic matter decomposing means used in the organic matter removing device according to the present invention.

FIG. 3 is a schematic view showing an example of an organic matter decomposing means used in the organic matter removing device according to the present invention.

FIG. 4 is a schematic diagram showing an example of an organic matter decomposing means used in the organic matter removing device according to the present invention.

FIG. 5 is a schematic view showing an example of an organic matter decomposing means used in the organic matter removing device according to the present invention.

FIG. 6 is a schematic view showing an example of an organic matter decomposing means used in the organic matter removing device according to the present invention.

FIG. 7 is a schematic view showing an example of an organic matter decomposing means used in the organic matter removing device according to the present invention.

FIG. 8 is a schematic view showing an example of an electrodialysis device used for the organic matter removing device according to the present invention.

FIG. 9 is a flowchart showing another embodiment of the organic matter removing apparatus according to the present invention.

FIG. 10 is a graph showing the relationship between the pH of water to be treated and the rate of oxidative decomposition of organic substances.

FIG. 11 is a flowchart illustrating an example of an ultrapure water production apparatus.

[Explanation of symbols]

 32 Organic matter decomposing means 34 Branch flow path 36 Activated carbon filtration device 38 Electrodialysis device 40 TOC meter 130 Organic substance decomposition means 134 Activated carbon filtration device 136 Ion exchange tower 138 TOC meter

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI C02F 1/72 C02F 1/72 101 101 1/46 103

Claims (8)

[Claims] When decomposing organic substances in water containing organic substances using an organic substance decomposing means for decomposing organic substances contained in the water to be treated by adding ozone to the water to be treated,
The treated water of the organic matter decomposing means is passed through at least an ion exchange means using an anion exchange resin, and the organic matter concentration in the treated water of the ion exchange means is measured by an organic matter concentration measuring means. A method for removing organic substances in water, comprising controlling the amount of ozone added to the water to be treated in the organic substance decomposition means based on the measured value of the organic substance concentration. 2. Decomposing organic matter in water containing organic matter by using organic matter decomposing means for decomposing organic matter contained in the water to be treated by adding ozone under alkaline conditions to the water to be treated. The treated water is passed through at least an ion exchange means using an anion exchange resin, and the organic matter concentration in the treated water of the ion exchange means is measured by the organic matter concentration measuring means, and the organic matter concentration measured by the organic matter concentration measuring means is measured. A method for removing organic substances in water, comprising controlling the amount of ozone added to the water to be treated in the organic substance decomposition means based on the value. 3. Adding ozone to the water to be treated,
When decomposing the organic matter in the organic matter-containing water using an organic matter decomposing means that decomposes the organic matter contained in the water to be treated by irradiating the water to be treated with ozone with ultraviolet rays, the treated water of the organic matter decomposing means is at least shaded. Water is passed through the ion exchange means using the ion exchange resin, and the organic matter concentration in the treated water of the ion exchange means is measured by the organic matter concentration measurement means, and the organic matter concentration is measured based on the value of the organic matter concentration measured by the organic matter concentration measurement means. A method for removing organic substances in water, comprising controlling the amount of ozone added to the water to be treated and / or the amount of ultraviolet irradiation in the organic substance decomposition means. 4. An organic matter decomposing means for decomposing organic substances in water containing organic substances by using an organic substance decomposing means for decomposing organic substances contained in the water to be treated by adding ozone and hydrogen peroxide to the water to be treated. The treated water is passed through at least an ion exchange means using an anion exchange resin,
The organic matter concentration in the treated water of the ion exchange means is measured by the organic matter concentration measuring means, and the ozone and / or excess water in the water to be treated in the organic matter decomposing means is determined based on the value of the organic matter concentration measured by the organic matter concentration measuring means. A method for removing organic substances in water, comprising controlling the amount of hydrogen oxide added. 5. An organic substance decomposing means which decomposes organic substances contained in the water to be treated by adding hydrogen peroxide to the water to be treated and irradiating the water to be treated with the hydrogen peroxide with ultraviolet rays. In decomposing the organic matter in the contained water, the treated water of the organic matter decomposing means is passed through at least an ion exchange means using an anion exchange resin, and the concentration of the organic matter in the treated water of the ion exchange means is measured by the organic matter concentration measuring means. And controlling the amount of hydrogen peroxide added to the water to be treated and / or the amount of ultraviolet irradiation in the organic substance decomposing means based on the value of the organic substance concentration measured by the organic substance concentration measuring means. Removal method. 6. Addition of persulfuric acid and / or persulfate as an oxidizing agent to the water to be treated, and heat treatment of the water to which the persulfuric acid and / or persulfate is added is included in the water to be treated. In decomposing the organic substance in the organic substance-containing water by using the organic substance decomposing means for decomposing the organic substance, the treated water of the organic substance decomposing means is passed through at least an ion exchange means using an anion exchange resin. The organic matter concentration in the treated water is measured by the organic matter concentration measuring means, and the addition of persulfuric acid and / or persulfate to the water to be treated in the organic matter decomposing means is performed based on the value of the organic matter concentration measured by the organic matter concentration measuring means. A method for removing organic matter in water, comprising controlling the amount. 7. A branch channel for diverting a part of the treated water of the organic substance decomposing means is provided on the downstream side of the organic substance decomposing means, and at least an ion exchange means using an anion exchange resin is provided in the branch flow path. The treated water of the organic matter decomposing means which has been diverted to the branch flow path is passed through the ion exchange means, and the organic matter concentration in the treated water of the ion exchange means is measured by the organic matter concentration measuring means. The method for removing organic substances in water according to any one of the above. 8. The water according to any one of claims 1 to 7, wherein an electrodialysis device using an anion exchange resin and a cation exchange resin is used as an ion exchange means using at least an anion exchange resin. Organic matter removal method.