JP2002001366A - Method and system for treating organic substance in water - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a treating method and system for organic substances having high decomposition efficiency and capable of minimizing a required quantity of ozone in the treating system of organic substance containing water using both ozone and hydrogen peroxide in combination. SOLUTION: Plural dissolving means 131, 132 for generating fine bubbles of the ozone-containing gas to dissolve in water to be treated and oxidizing and plural gas introducing means 141, 142 for introducing the ozone-containing gas into the dissolving means are provided and the ozone-containing gas introduced into at least >=1 dissolving means contains at least the ozone-containing gas passed through the water to be treated at least >=1 times and discharged on the liquid surface of the water to be treated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for treating organic matter in water, and more particularly to an efficient oxidation treatment of wastewater containing organic matter generated in a semiconductor or liquid crystal manufacturing process by reducing the amount of ozone used. The present invention relates to a method and an apparatus for treating underwater organic substances.

[0002]

2. Description of the Related Art Today, global demands for effective use of resources have been increasing from the standpoint of environmental protection of the earth, and there has been an increasing movement to reuse water in semiconductors and liquid crystal factories that have consumed large amounts of water. is there.

[0003] In the production process of semiconductors and liquid crystals, a large amount of organic solvents are used for removing photoresists and the like.
Examples of the organic substance used include IPA (isopropyl alcohol), DMSO (dimethyl sulfoxide), TMAH (tetramethylammonium hydroxide) and acetone, and it is necessary to remove these organic components from the wastewater. .

[0004] As a method for removing organic substances, direct adsorption using activated carbon or the like or decomposition of organic substances by a powerful oxidizing means has been used. CO ₂ and organic acids generated by decomposition by the latter oxidizing means are removed by an ion exchange resin or the like. By decomposing organic matter in this way, it is possible to reuse wastewater containing a large amount of organic matter.

As other means for decomposing organic substances, use of ultraviolet rays or use of microorganisms has been carried out. When ultraviolet rays are used, ozone or H ₂
Accelerators such as O ₂ have been used in combination. However, in the decomposition treatment using microorganisms, it is difficult to treat hardly decomposable organic substances, and in the treatment using ultraviolet rays, there is a problem that a large economical load is required to consume a large amount of electric energy.

In recent years, attention has been paid to a method using ozone as a new means for decomposing organic substances. In this case, by using hydrogen peroxide as an accelerator in addition to the ozone gas, efficient decomposition of organic substances becomes possible. This is because the influence of hydrogen peroxide further increases the generation of hydroxyl radicals (OH radicals) and can efficiently decompose organic substances in water.

[0007] An organic substance treating apparatus using both ozone and hydrogen peroxide is composed of an ozone generator, a raw material gas pretreatment apparatus, a reaction tank, an exhausted ozone gas treatment apparatus and the like. Also, an oxidizing agent treatment apparatus for treating ozone and hydrogen peroxide not used in the reaction from the treated water treated in the reaction tank, and a means for removing CO ₂ and organic acids generated by decomposition of organic matter, for example, ion exchange A device and the like are added (JP-A-11-114584).

FIG. 5 shows a conventional organic substance processing apparatus using ozone gas, in which an ozone generator 511 and a reaction tank 521 are provided.
And gas dissolving means 531. The ozone generator 511 is connected to a pretreatment device 510 for the gas. The reaction tank 521 is filled with the water 561 to be treated. The gas dissolving means 531 is provided in the reaction tank 521 so as to be immersed in the water 561 to be treated, and is connected to an ozone generator by a pipe 541. A supply pipe 571 is connected to the inside of the reaction tank 521, and H ₂ O ₂ 581 and a pH adjuster 582 are supplied to the water 5 through the supply pipe 571.
61. Further, a waste gas treatment device 584 for treating ozone or H ₂ O ₂ extracted from the water to be treated 561 without being used for the oxidation treatment is connected to the reaction tank 521.

In such an apparatus, the water to be treated 561 is H
₂ O ₂ and a pH adjuster such as NaOH are mixed, and ozone gas from the ozone generator 511 is blown out from the gas dissolving means 531 to oxidize the water 561 to be treated. Oxidizing agents, oxidative decomposition products such as carbon dioxide and organic acids remaining in the oxidized water to be treated 561 are removed by an activated carbon adsorption device or an ion exchange device.

[0010] As the ozone generator 511, an apparatus for generating ozone by silent discharge is usually used. In the silent discharge, the source gas processed by the source gas pretreatment device 510 is passed through an ozone generator 511 to apply an AC voltage to perform a discharge, thereby generating ozone. The raw material gas pretreatment device 510 generates a gas having an oxygen concentration of 80% or more using air as a raw material. The ozone generator 511 also uses a cooling device because heat is generated by discharge. The waste gas treatment device 584 removes ozone remaining in the waste gas with a catalyst resin or the like, and then discharges the ozone into the atmosphere.

The gas dissolving means 531 introduces a gas into a liquid by passing through a fine hole, or introduces a gas by a rotating blade.

Further, instead of a gas dissolving means for dissolving a gas in a liquid, a reaction vessel of such an organic substance treating apparatus is provided with:
Some use a packed tower that dissolves a liquid in a gas.

In a reaction vessel using a packed tower, the treatment can be carried out in a multi-stage system. Therefore, by successively reusing the waste gas, the ozone concentration of the waste gas can be reduced as much as possible. However, since the use efficiency of ozone is lower than that of the gas dissolving means, the required ozone amount is not much different from that of the rotary blade type gas dissolving means. That is, the packed tower can efficiently absorb ozone, but it is not efficient in using the absorbed ozone for the reaction, and conversely, the gas dissolving means efficiently uses the absorbed ozone for the reaction. Despite this, the absorption efficiency is poor, and the percentage of ozone that escapes into the waste gas is large. Each has advantages and disadvantages and is used according to the purpose.

[0014]

In such a conventional organic matter treatment apparatus, the efficiency of use of ozone in a reaction tank is poor, and a large amount of ozone is consumed. Therefore, it is not economically preferable. In addition, since ozone is an air pollutant, it is desired to minimize its use. In the conventional apparatus, ozone not consumed in the reaction is released into the atmosphere via the waste gas treatment device 40 in the reaction tank 32, and thus there is a problem that such a demand cannot be met.

On the other hand, with the recent miniaturization of LSIs and ULSIs, the demand for the purity of pure water used in the production thereof has been increasing, and water containing organic substances using both ozone and hydrogen peroxide has been required. It has been required to obtain a high decomposition rate also in the processing apparatus of (1).

When oxidative decomposition of an organic substance is performed using a conventional organic substance processing apparatus employing such a gas dissolving means, the higher the decomposition rate of the organic substance is, the greater the required amount of ozone is. It is high. That is, when the decomposition rate of TOC is low, the ozone utilization efficiency is relatively high, but when the decomposition efficiency of TOC is improved, the ozone utilization efficiency tends to deteriorate.

For example, when the concentration of IPA is 1 as organic carbon,
The amount of ozone required to treat the water to be treated, which is 0 ppm, is ΔO _{3 /} ΔTOC (g / g) = 15.0 if the concentration of the treated water is 2 ppm as organic carbon.
If the target is ppm, ΔO ₃ / ΔTOC (g / g) = 18.
Had increased to seven.

Further, in a conventional apparatus for treating organic matter in water employing gas dissolving means, not all of the ozone which has been increased to improve the decomposition efficiency is necessarily used for the reaction of organic matter, and most of the ozone is not used for the reaction. It remains as waste gas. For example, when the above-mentioned water to be treated having an IPA concentration of 10 ppm is removed to 2 ppm, the ratio of ozone remaining in waste gas without being used for the reaction in ozone supplied to the reaction tank from the ozone generator. Is about 20%, and when it is further removed to 1 ppm, it is about 40%. From this, when the decomposition efficiency is improved, the use efficiency of ozone is rather lowered.

Therefore, in the present invention, the decomposition efficiency is high,
Further, it is an object of the present invention to provide a method and an apparatus for treating organic matter in water using both ozone and hydrogen peroxide, which can minimize the required amount of ozone.

[0020]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a method for treating organic matter in water, wherein ozone and hydrogen peroxide are used in combination to treat water to be treated. The method further comprises one or more processing steps for dissolving ozone in the water to be treated and oxidizing it by generating microbubbles of the introduced ozone-containing gas in the treated water. Ozone-containing gas
It is characterized by including at least an ozone-containing gas that has passed through the water to be treated one or more times and was discharged onto the surface of the water to be treated.

In this treatment method, the water to be treated is sequentially transferred to one or more reaction tanks in a subsequent treatment step, or the one or more treatment steps introduce an ozone-containing gas from an ozone generator. It is preferable to perform the oxidation treatment and the oxidation treatment for introducing the ozone-containing gas discharged onto the surface of the water to be treated after passing through the water to be treated at least once.

In the above-mentioned method for treating organic matter in water, the treatment step of oxidizing the water to be treated is preferably a method in which fine bubbles of an ozone-containing gas are generated by rotating blades and dissolved in the water to be treated.

Further, in the underwater organic matter treatment apparatus for treating water to be treated by using ozone and hydrogen peroxide in combination according to the present invention, ozone is dissolved in the water to be treated by generating fine bubbles of an ozone-containing gas. And a plurality of gas introducing means for introducing an ozone-containing gas into the dissolving means. The ozone-containing gas introduced into at least one or more dissolving means is subjected to at least one treatment. It is characterized by including at least an ozone-containing gas discharged through the water and discharged onto the surface of the water to be treated.

In this organic substance treatment apparatus, the dissolving means is provided for each treatment step of oxidizing the water to be treated.
It is preferable that one or more of the above-described reaction tanks are provided, and that the water to be treated is sequentially transferred to one or more reaction tanks in a subsequent processing step.

Alternatively, there is provided at least one reaction tank filled with water to be treated, and at least one reaction tank has a dissolving means for introducing an ozone-containing gas from an ozone generator, and at least one treatment tank. And at least one dissolving means for introducing the ozone-containing gas discharged onto the liquid surface of the water to be treated after passing through.

In the above-mentioned apparatus for treating organic matter in water, the dissolving means generates fine bubbles by means of rotating blades of the introduced gas and dissolves them in the water to be treated.

According to the organic substance treating method and the treating apparatus of the present invention, in the reaction tank which has been subjected to the oxidation treatment, surplus ozone not consumed in the reaction is provided in another reaction tank. It is sent to the dissolving means or to the dissolving means of the same reaction tank, and can be reused for oxidative decomposition of organic substances contained in the water to be treated filled in the reaction tank. Achieve both improvement of decomposition efficiency.

[0028]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a sectional view showing a first embodiment of an apparatus for treating organic matter in water according to the present invention. The organic matter processing apparatus mainly includes an ozone generator 11, a reaction tank 121,
122, dissolving means 131 and 132, gas introducing means 1
41 and 142 are provided.

The ozone generator 11 is a source gas pretreatment device 1
Connected to 0. The water to be treated 161 is placed in the reaction tank 121.
Is filled. The dissolving means 131 is provided in the reaction tank 121 so as to be immersed in the water 161 to be treated, and is connected to the ozone generator 11 by the gas introducing means 141 from the ozone generator 11. Thereby, an ozone-containing gas is introduced. A supply pipe 71 is connected to the reaction tank 121, and H ₂ O ₂ 81 and PH are supplied through the supply pipe 71.
The adjusting agent 82 is mixed with the water 161 to be treated.

The water 16 to be treated placed in the reaction tank 121
1 is mixed with H ₂ O ₂ 81 and a pH adjuster 82, and an ozone mixed gas introduced from a gas introduction unit 141 is ejected as fine bubbles from a dissolving unit 131, whereby organic matter in the water to be treated 161 is discharged. Is oxidized.

The reaction tank 122 is connected to the pipe 7 from the reaction tank 121.
The water to be treated 161 oxidized in the reaction tank 121 is transferred and filled by the reaction tank 121. The dissolving means 132 is provided so as to be immersed in the water 162 to be treated.
2. The gas introduction means 142 is drawn out from the top of the reaction tank 121, and the tip is connected to the melting means 132. Thereby, the gas introduction unit 142 acts to introduce the excess ozone-containing gas remaining in the reaction tank 121 to the dissolution unit 132.

The water to be treated 162 transferred into the reaction tank 122
The reaction tank 1 introduced by the gas introduction means 142
The residual ozone-containing gas is jetted from the dissolving means 132 as fine bubbles into the water 21 to be treated 162.
The organic matter in it is oxidatively decomposed.

At the top of the reaction tank 122, there is provided a discharge pipe 83 for discharging the ozone mixed gas remaining after the reaction and connected to a waste gas treatment device 84.

A drain pipe 85 extends from the reaction tank 122 to the adsorber 8.
6, and a drain pipe 87 from the adsorber 86 is connected to the ion exchanger 88. The adsorber 86 is filled with an adsorbent such as activated carbon. As a result, the water 162 subjected to the oxidative decomposition treatment in the reaction tank 122 is discharged, and the ozone, H ₂ O _{2, and the} like remaining in the water 162 are removed by adsorption. The water to be treated 162 is discharged to the ion exchanger 88 via the drain pipe 87, and the ion exchanger 88 removes oxidative decomposition products such as organic acids and trace amounts of carbon dioxide in the water to be treated 162.

In the first embodiment, the necessary
Between the reaction tank 121 and the reaction tank 122 according to
By installing the above reaction tank, ozone gas remaining without being consumed
Reuse can also be increased. In this case, the reaction tank
121 is connected to a reaction tank 122, and
Same as the pipe 72 for transferring the treated water 161
Is provided for each additional reaction tank. Also the reaction
It is pulled out from the top of the tank 121 and the tip is
32 and the same gas as the gas introduction means 142 connected to
An introduction means and a dissolution means are provided in each reaction tank. More
Water to be treated to be filled in each installed reactor and the reactor 12
2 to be treated water 162 filled in H₂O ₂81 and p
A supply pipe for mixing the H regulator 82 is connected to each reaction tank.
You.

FIG. 2 is a cross-sectional view showing a second embodiment of the apparatus for treating organic matter in water according to the present invention, in which a gas introducing means is installed in a direction opposite to the flow of the ozone mixed gas of the first embodiment. It is.

In the processing apparatus according to the second embodiment, a supply pipe 71 is connected to a reaction tank 221, and H ₂ O ₂ 81 and a pH adjuster 82 are connected through the supply pipe 71.
Is mixed with the water to be treated 261 and filled in the reaction tank 221. The dissolving means 231 provided in the reaction tank 221 has gas introduction means 242 drawn out from the top of the reaction tank 222.
Are connected. Thereby, the gas introduction means 2
42 introduces the ozone-containing gas after the oxidation treatment in the reaction tank 222 into the dissolving means 231 to generate fine bubbles of the ozone mixed gas.

The water 26 to be treated placed in the reaction tank 221
1 is mixed with H ₂ O ₂ 81 and a pH adjuster 82, and an ozone mixed gas introduced from a gas introduction unit 242 is ejected as fine bubbles from a dissolution unit 231, whereby organic matter in the water to be treated 261 is discharged. Is oxidized.
At the top of the reaction tank 221, there is provided a discharge pipe 83 for discharging the ozone mixed gas remaining after the reaction and connected to a waste gas treatment device 84.

The reaction tank 222 is connected to the pipe 7 from the reaction tank 221.
2, and the water to be treated 261 oxidized in the reaction tank 221 is transferred and filled. The dissolving means 232 is provided in the reaction tank 22 so as to be immersed in the water to be treated 262.
2, the dissolving means 232 includes an ozone generator 1
1 to the ozone generator 11 by gas introducing means 241. Thereby, the ozone-containing gas is introduced into the dissolving means 232, and fine bubbles of the ozone-containing gas are generated.

The water to be treated 262 transferred into the reaction tank 222
The organic matter in the water to be treated 262 is oxidatively decomposed by ejecting the ozone-containing gas introduced by the gas introducing means 241 as fine bubbles from the dissolving means 232.

The connection form from the reaction tank 222 to the adsorber 86 and from the adsorber 86 to the ion exchanger 88 is the same as in the first embodiment, and the water to be treated 262 oxidized and decomposed in the reaction tank 222 is connected. Is discharged, and ozone, H ₂ O _{2, and the} like remaining in the water to be treated 262 are adsorbed and removed by the adsorber 86. Further, the water to be treated 262 is discharged to an ion exchanger 88 via a drain pipe 87, and in the ion exchanger 88, oxidative decomposition products such as organic acids and trace amounts of carbon dioxide in the water to be treated 262 are removed. .

In the second embodiment, when the ozone-containing gas remains without being consumed in the oxidation treatment in the reaction tank 221, the ozone-containing gas may be further reused if necessary. Can be. In this case, one or more reaction tanks are further installed between the reaction tanks 221 and 222, and a gas introduction unit similar to the gas introduction unit 242 is sequentially provided from the reaction tank 222 to the reaction tank 221. Alternatively, one or more reaction tanks may be further provided at the subsequent stage of the reaction tank 222 so that the gas introduction means 242 from the reaction tank 222 to the reaction tank 221 crosses the direction of introducing the ozone-containing gas. It is.

In the case of the processing apparatus modified to the former embodiment, a pipe similar to the pipe 72 connected from the reaction tank 221 to the reaction tank 222 and transporting the water to be treated 261 oxidized in the reaction tank 221 is provided. , Provided in each additional reaction tank. Further, the gas introduction means 24 which is withdrawn from the top of the reaction tank 222 and whose tip is connected to the melting means 231
The same gas introducing means and dissolving means as in 2 are equipped in each reaction tank. Furthermore, H ₂ O is added to the water to be treated filled in each of the additionally installed reaction tanks and the water to be treated 262 filled in the reaction tank 222.
₂ 81 and the supply pipe for mixing the pH adjuster 82 is connected to each reaction vessel.

In the case of the processing apparatus modified in the latter form, a pipe similar to the pipe 72 for transferring the water to be treated 261 oxidized in the reaction tank 221 is provided for each additional reaction tank. Also, it is installed at the top of the reaction tank 221,
Instead of the discharge pipe 83 connected to the waste gas treatment device 84, the same gas introducing means and melting means as the gas introducing means 242 which is drawn out from the top of the reaction tank 222 and whose tip is connected to the melting means 231 are used. Provided in each reaction layer. Furthermore, H ₂ O ₂ 81 is added to the water to be treated filled in each of the additionally installed reaction tanks and the water to be treated 262 filled in the reaction tank 222.
And a supply pipe for mixing the pH adjuster 82 is connected to each reaction tank.

FIG. 3 is a sectional view showing a third embodiment of the apparatus for treating organic matter in water according to the present invention, which is a processing apparatus equipped with a plurality of gas introducing means which are branched and connected respectively.

The organic matter processing apparatus according to the third embodiment mainly includes an ozone generator 11 and reaction tanks 321 and 32.
2, 323, dissolving means 331, 332, 333 and gas introducing means 341, 342, 343, 344. A supply pipe 71 is connected to the reaction tank 321.
H ₂ O ₂ 81 and pH adjuster 8 via supply pipe 71
2 is mixed with the water to be treated 361 and filled in the reaction tank 321. The dissolving means 331 is provided in the reaction tank 321 so as to be immersed in the water 361 to be treated.
1 to the ozone generator 11 by gas introducing means 341. The gas introduction unit 341 has a branch 351 that branches to the gas introduction unit 342.

The water to be treated 36 placed in the reaction tank 321
1 is mixed with H ₂ O ₂ 81 and a pH adjuster 82, and an ozone mixed gas introduced from a gas introduction unit 341 is ejected as fine bubbles from a dissolution unit 331, whereby the water in the water to be treated 361 is discharged. Organic matter is oxidized.

The reaction tank 322 is connected to the pipe 7 from the reaction tank 321.
2, and the water to be treated 361 oxidized in the reaction tank 321 is transferred. The dissolving means 332 is provided in the reaction tank 322 so as to be immersed in the water to be treated 362. The gas introduction means 342 is
The ozone-containing gas is introduced from the ozone generator 11, which is connected to the first branch 351 and connected to the tip of a dissolving means 332 provided in the reaction tank 322.

The water to be treated 36 filled in the reaction tank 322
2, the ozone-containing gas introduced by the gas introduction unit 342 is ejected as fine bubbles from the dissolution unit 332, so that the organic matter in the water to be treated 362 is oxidized.

The reaction tank 323 is connected to the pipe 7 from the reaction tank 322.
3, and the water to be treated 362 oxidized in the reaction tank 322 is transferred. The dissolving means 333 is provided in the reaction tank 323 so as to be immersed in the water 363 to be treated. The dissolving unit 333 has a gas introducing unit 343 having a connecting portion 352 for connecting the gas introducing units from the top of the reaction tank 321 and a gas introducing unit connected to the connecting portion 352 of the gas introducing unit 343 from the top of the reaction tank 322. The tip of the means 344 is connected. Gas introduction means 34
3 and the gas introducing means 344 connected to the connecting portion 352, the ozone-containing gas remaining after the oxidation treatment in the reaction tank 321 and the ozone-containing gas remaining after the oxidation treatment in the reaction tank 322 are mixed and introduced into the melting means 333. Is done.

The water to be treated 363 filled in the reaction tank 323
The organic matter in the water to be treated 363 is oxidized by ejecting the ozone-containing gas introduced by the gas introduction means 343 and 344 as fine bubbles from the dissolution means 333. An exhaust pipe 83 for discharging the ozone-containing gas remaining after the oxidative decomposition treatment from the top of the reaction tank 323 and connected to a waste gas treatment device 84 is provided.

From the reaction tank 323, a drain pipe 85 is connected to the adsorber 86, and a drain pipe 87 from the adsorber 86 is connected to the ion exchanger 88. As a result, the water 162 subjected to the oxidative decomposition treatment in the reaction tank 122 is discharged, and the ozone, H ₂ O _{2, and the} like remaining in the water 162 are removed by adsorption. The water to be treated 162 is discharged to the ion exchanger 88 via the drain pipe 87, and the ion exchanger 88 removes oxidative decomposition products such as organic acids and trace amounts of carbon dioxide in the water to be treated 162.

Further, in the organic matter treating apparatus of the third embodiment, one or more additional reaction tanks may be additionally installed or the gas introducing means may be branched via valve means such as a three-way valve or a four-way valve. It can be modified to a form in which a plurality of gas introducing means having a connecting branch portion and a connecting portion are further combined and equipped. In the processing apparatus modified in this way, the branch means in each gas introduction means provided in combination with a large number of gas introduction means, and the valve means of the connection part are switched according to the purpose, so that each treatment tank is provided. It is possible to introduce variously mixed ozone-containing gases for each dissolving means. For example, an ozone-containing gas from a plurality of reaction tanks after the oxidation treatment is mixed, and an ozone-containing gas obtained by additionally mixing an ozone-containing gas from an ozone generator is introduced into the dissolving unit, or during the oxidative decomposition reaction. Alternatively, the ozone-containing gas remaining in the other reaction tank after the oxidation treatment or the ozone-containing gas from the ozone generator can be additionally introduced into the melting means.

FIG. 4 is a sectional view showing a fourth embodiment of the apparatus for treating organic matter in water according to the present invention, which is a processing apparatus equipped with a plurality of gas introducing means and a plurality of dissolving means in one reaction tank.

In the processing apparatus of the fourth embodiment, a plurality of dissolving means 431 and 432 are provided in the reaction tank 421, and gas introducing means 441 and 442 are connected to the dissolving means 431 and 432, respectively. The ozone generator 11 is a source gas pretreatment device 10
And the reaction tank 421 is filled with the water to be treated 461. The dissolving means 431 is provided in the reaction tank 421 so as to be immersed in the water to be treated 461, and is connected to the ozone generator 11 by the gas introducing means 441 from the ozone generator 11. Thereby, an ozone-containing gas is introduced. A supply pipe 71 is connected to the reaction tank 421, and H ₂ O ₂ 81 and a pH adjuster 82 are mixed with the water to be treated 461 via the supply pipe 71.

The water 46 to be treated placed in the reaction tank 421
1 is mixed with H ₂ O ₂ 81 and a pH adjuster 82, and an ozone mixed gas introduced from a gas introduction unit 441 is ejected as fine bubbles from a dissolution unit 431, whereby organic matter in the water to be treated 461 is discharged. Is oxidized.

The dissolving means 432 is provided in the reaction tank 421 so as to be immersed in the water 461 to be treated. The gas introduction means 442 is drawn out from the top of the reaction tank 421, and its tip is connected to the melting means 432. As a result, the gas introduction means 442 is
The excess ozone-containing gas discharged through the water to be treated 461 and discharged on the liquid surface is introduced into the dissolving means 432.

The remaining ozone-containing gas introduced into the reaction tank 421 by the gas introduction means 442 is ejected from the dissolving means 432 as fine bubbles into the water to be treated 461 in the reaction tank 421, whereby the water to be treated is The organic matter in 461 is oxidatively decomposed. Here, the ozone-containing gas introduced into the dissolving means 432 is ejected as fine bubbles from the dissolving means 431, and is not consumed by oxidative decomposition, but is not consumed.
In addition to the ozone-containing gas that has passed through 61 and is discharged to the top of the reaction tank, the ozone-containing gas that has been ejected from the dissolving means 432 and has passed through the water to be treated 461 at least once is also included. Can be Also, the dissolving means 4
31 and 432 to the gas introduction means 441 and 4 respectively.
It is also possible to introduce them in parallel from step 42, and it can be controlled according to the purpose such as the ozone concentration and the oxidation treatment speed.

At the top of the reaction tank 421, a discharge pipe 83 for discharging waste gas remaining after the reaction and connected to a waste gas treatment device 84 is provided.

From the reaction tank 421, a drain pipe 85 is connected to the adsorber 8
6, and a drain pipe 87 from the adsorber 86 is connected to the ion exchanger 88. The adsorber 86 discharges the water to be treated 461 that has been oxidatively decomposed in the reaction tank 421, and adsorbs and removes ozone, H ₂ O _{2, and the} like remaining in the water to be treated 461. The to-be-treated water 461 is discharged to the ion exchanger 88 via the drain pipe 87. In the ion exchanger 88, oxidative decomposition products such as organic acids and trace amounts of carbon dioxide in the to-be-treated water 162 are removed.

As the raw material gas pretreatment apparatus 10 provided commonly to the processing apparatuses of the respective embodiments, any apparatus can be used as long as it can generate a gas having an oxygen concentration of 80% or more using air as a raw material. As the ozone generator 11, there are devices such as a silent discharge system, an electrolysis system, a photochemical reaction system, a chemical reaction system, a radiation irradiation system, and a high-frequency electric field system, and any of them can be used. But,
A silent discharge type ozone generator that includes a cooling device and applies an AC voltage is preferable.

Dissolving means 131, 132, 231, 23
As 2, 3, 331, 332, 333, 431 and 432, any type of device can be used as long as it can eject the ozone-containing gas introduced from the gas introduction means as fine bubbles. A device of the type with or with rotating wings is desirable. The dissolving means 132, 231, 333, 431, and 432 include
In particular, devices of the type having rotating wings are preferred. In the case of using a device having a pore, a gas introducing means is equipped with a booster such as a blower.

The adsorber 86 may be a device comprising a column filled with activated carbon as an adsorbent, and the ion exchanger 88 may be a device comprising a column filled with a cation exchanger and an anion exchanger. A regenerative or non-regenerating mixed bed type apparatus packed with a cation exchange resin and a strongly basic anion exchange resin is suitable. The waste gas treatment device 84 is preferably a device that includes a catalytic resin and decomposes ozone in the waste gas.

Although the apparatus for treating organic matter in water according to the present invention has been described above with reference to the first to fourth embodiments, including the modified apparatus, various other modifications are possible within the technical scope of the present invention. It can be configured in a modified form. In the organic substance treatment apparatus configured in various forms as described above, an appropriate form is selected according to the type and concentration of the organic substance contained in the water to be subjected to the oxidation treatment.

Next, a method for treating organic substances in water according to the present invention using the above-described organic substance treating apparatus will be described.

The treatment method by the treatment apparatus of the first embodiment is such that water to be treated 161 put in the reaction tank 121 is
The ozone-containing gas introduced from the ozone generator 11 into the dissolving means 131 via the gas introducing means 141 is dissolve in the dissolving means 1
An oxidizing process for dissolving the ozone-containing gas as fine bubbles by 31 and water 161 after the oxidizing process in the reaction tank 121 are transferred to the reaction tank 122 via the pipe 72 and then oxidized from the reaction tank 121. The ozone-containing gas remaining without being consumed in the processing step is taken out through the gas introducing means 142, and fine bubbles of the ozone-containing gas are generated by the dissolving means 132 and dissolved in the water to be treated 162.
And an oxidation treatment step of dissolving.

The water to be treated 161 to be put into the reaction tank 121
H through the supply pipe 71₂O ₂Inject 81.
The injection concentration is ΔH₂O₂/ ΔO₃(g / g) = about 1-3 is good
No. This H₂O₂Depends on various conditions.
Determined, but H₂O₂OH generated when concentration is too low
If the radicals are insufficient and too high, the generated OH radicals
H₂O₂Attack on the robot will be inefficient. Note that H₂O
₂The injection of 81 does not necessarily mean that the water 161 to be treated
1 and need not be supplied to the reaction tank 121.
The injection may be directly through the pipe 71.

The pH adjusting agent 82 is injected into the water 161 to be treated into the reaction tank 121 through the supply pipe 71. Usually, an alkali such as NaOH or KOH is used as the pH adjuster 82. This controls the pH at the outlet of the reaction tank 121 to the pipe 62 to a neutral or weakly alkaline side. On the acidic side, the generation of OH radicals is not sufficient, and at high alkalinity, carbonate ions as scavengers have an adverse effect. In addition, since the pH of the water to be treated 161 becomes acidic due to the ozone reaction, the water is supplied to the reaction tank 121 via the supply pipe 71 as needed, not only at the time of filling the reaction tank but also after the end of the oxidation treatment step. The pH adjuster 22 is injected, and the pH at the outlet of the reaction tank 121 is controlled to an appropriate pH.

The control of the injection amount and pH of H ₂ O ₂ 71 slightly affects the performance of removing organic substances in the oxidation treatment step. The H ₂ O ₂ 71 and / or the pH adjuster 22 are further injected into the water to be treated 161 via the supply pipe 71. This makes it possible to perform processing under appropriate processing conditions even in the subsequent oxidation processing step in the reaction tank 122.

The organic substances to be oxidatively decomposed have different reactivities with hydroxyl radicals for each substance. In order to carry out the oxidative decomposition treatment efficiently, the type, concentration and reaction of the organic substances contained in the water to be treated are different. The optimum ozone concentration, hydrogen peroxide concentration, and pH in each of the water to be treated vary depending on the progress state of the water. Depending on the type and concentration of the organic matter contained in the water to be subjected to the oxidation treatment, a suitable type of processing apparatus is selected from the processing apparatuses of the first to fourth embodiments and the processing apparatuses configured in respective modified forms. To perform oxidative decomposition treatment.

According to the organic substance treating method and the treating apparatus of the present invention, the excess ozone that has passed through the water to be treated one or more times and is discharged onto the surface of the water to be treated and is not consumed in the reaction but becomes excessive. Is sent to another reaction tank or the dissolving means of the same reaction tank through the gas introduction means, and can be reused for oxidative decomposition of organic substances remaining in the water to be treated without being oxidatively decomposed. It achieves both improvement in efficiency and improvement in decomposition efficiency of organic substances. In addition, since the oxidative decomposition treatment can be performed by selecting a treatment apparatus having an appropriate form according to the type and concentration of the organic substance contained in the water to be treated, the present invention is applicable to water to be treated containing various organic substances.

Hereinafter, the present invention will be described specifically with reference to examples, but the present invention is not limited thereto.

[0074]

EXAMPLE The water to be treated was treated using the treatment apparatus shown in FIG. 1 under the following conditions. As the water to be treated, total organic carbon (TO
IPA containing 10 ppm was used as C). In the treatment apparatus shown in the figure, the adsorber was originally installed to remove ozone and hydrogen peroxide, but the activated carbon filled in the adsorber also has an organic matter removal ability. In consideration of the effect of evaluating the ozone oxidation treatment capacity, it was not used in this example.

The processing flow rate of the IPA was 0.5 m ³ / h,
The ozone concentration in the ozone-containing gas was set to 120 g / m ³ , the amount of hydrogen peroxide used in combination with ozone was set to 20 ppm, and Na was added.
The pH at the outlet of the reactor was adjusted to 7.0 to 8.0 with OH.

FIG. 4 shows a processing apparatus of a comparative example for this embodiment, and the same elements as those of FIG. 1 are denoted by the same reference numerals. In the processing apparatus of FIG. 4, a branch pipe 151 is connected to the gas introducing means 141 of the processing apparatus of FIG. By performing such a connection, the ozone-containing gas from the ozone generator 11 is supplied to the reaction tank 1 through the gas introducing means 141.
21 to the dissolving means 131 and the branch pipe 151.
Is supplied to the dissolving means 132 of the reaction tank 122 via the In this comparative example, an ozone-containing gas was introduced into each of the dissolving means 131 and the dissolving means 132 at a ratio of 1: 1. Further, the reaction tank 121 and the reaction tank 122
Waste gas from the waste gas treatment device 8 directly without reuse
Passed through 4. Other conditions are the same as in the embodiment. Also, in the conventional processing apparatus shown in FIG. 5, processing was performed under the same conditions as those of the example and the comparative example.

Tables 1 and 2 show the processing results of the example, the comparative example, and the conventional example.

[0078]

[Table 1]

[0079]

[Table 2]

As is clear from Table 1, in Examples of the present invention, higher removal performance was obtained than in Comparative Examples and Conventional Examples. In the comparative example, the removal performance is almost the same as the conventional example. Table 2 shows the amount of ozone necessary for the TOC concentration of the water to be treated to reach 1 or 0.5 ppm when IPA containing 10 ppm of carbon as the TOC concentration of the water to be treated is treated. As an indicator, △ _{O 3}
/ △ TOC (g / g) was used. As is clear from Table 2, in the examples of the present invention, the required amount of ozone was significantly reduced. In the comparative example, the required ozone amount was almost the same as the conventional example.

[0081]

As described above, according to the present invention,
Organic substances can be treated with high decomposition efficiency and minimum required ozone amount.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a first embodiment of a processing apparatus according to the present invention.

FIG. 2 is a sectional view showing a second embodiment of the processing apparatus according to the present invention.

FIG. 3 is a sectional view showing a third embodiment of the processing apparatus according to the present invention.

FIG. 4 is a sectional view showing a fourth embodiment of the processing apparatus according to the present invention.

FIG. 5 is a sectional view of a processing apparatus of a comparative example.

FIG. 6 is a sectional view of a conventional processing apparatus.

[Explanation of symbols]

 11 Ozone generator 121, 122 Reaction tank 131, 132 Dissolving means 141, 142 Gas introducing means 221, 222 Reaction tank 231, 232 Dissolving means 241, 242 Gas introducing means 321, 322, 323 Reaction tank 331, 332, 333 Dissolving means 341, 342, 343, 344 Gas introducing means 421, 422 Reaction tank 431, 432 Dissolving means 441, 442 Gas introducing means

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Shinsuke Sato 2-9-8 Okada, Atsugi-shi, Kanagawa F-term in Nomura Micro Science Co., Ltd. 4D024 AA04 AB14 BA02 CA01 DA04 DA05 DB19 DB23 DB24 4D050 AA13 AB07 AB14 AB17 AB18 BB02 BB09 BD03 BD06 BD08 CA06 CA08 CA13 4G035 AA01 AB10

Claims (8)

[Claims] 1. A method for treating organic matter in water, wherein ozone and hydrogen peroxide are used in combination to treat water to be treated, wherein fine particles of ozone-containing gas introduced into the water to be treated filled in at least one reaction tank are provided. Providing one or more treatment steps for dissolving ozone in the water to be treated and oxidizing by generating air bubbles, the ozone-containing gas introduced into at least one or more of the treatment steps is used to remove the water to be treated one or more times. A method for treating organic matter in water, comprising at least an ozone-containing gas that has passed through and has been discharged onto the surface of the water to be treated. 2. The method for treating organic matter in water according to claim 1, wherein the water to be treated is sequentially transferred to one or more reaction vessels in a subsequent treatment step. 3. The one or more treatment steps include an oxidation treatment for introducing an ozone-containing gas from an ozone generator and an ozone discharged at least once through the water to be treated and discharged onto the surface of the water to be treated. The method for treating organic matter in water according to claim 1, wherein the oxidation treatment for introducing the contained gas is performed in parallel. 4. The method according to claim 1, wherein the oxidation treatment is performed by generating fine bubbles of an ozone-containing gas by a rotating blade. 5. An underwater organic substance treatment apparatus for treating water to be treated using both ozone and hydrogen peroxide, wherein ozone is dissolved in the water to be treated and oxidized by generating fine bubbles of an ozone-containing gas. A plurality of dissolving means and a plurality of gas introducing means for introducing an ozone-containing gas into the dissolving means are provided, and the ozone-containing gas introduced into at least one or more of the dissolving means passes through the water to be treated at least once. An underwater organic matter treatment apparatus comprising at least an ozone-containing gas discharged onto the surface of water to be treated. 6. The dissolving means is provided in one or more reaction tanks provided for each treatment step for oxidizing the water to be treated, and the water to be treated is subjected to at least one reaction in a subsequent treatment step. The underwater organic matter treatment apparatus according to claim 5, wherein the apparatus is sequentially transferred to a tank. 7. At least one reaction tank filled with the water to be treated is provided, wherein at least one reaction tank has a dissolving means for introducing an ozone-containing gas from an ozone generator, and at least one reaction tank. 6. The organic matter in water according to claim 5, further comprising one or more dissolving means for introducing the ozone-containing gas discharged through the water to be treated and discharged onto the surface of the water to be treated. Processing equipment. 8. An apparatus for treating organic matter in water according to claim 5, wherein said dissolving means generates fine bubbles by means of blades rotating the introduced ozone-containing gas.