JP4936505B2 - Method and apparatus for treating ammonia-containing water - Google Patents

Description

  The present invention relates to a method for treating ammonia-containing water and a treatment apparatus used in the method.

Conventionally, wastewater containing ammonia is generated in a liquid crystal manufacturing factory and a semiconductor manufacturing factory. In order to collect this wastewater and reuse it as pure water, a process of evaporating and concentrating the wastewater has been performed. In addition, when waste water containing volatile nitrogen-containing compounds such as (CH ₃ ) ₄ NOH (TMAH) and H ₂ NCH ₂ CH ₂ OH (MEA) is discharged, the waste water may be subjected to a treatment for evaporation and concentration. is there.

  Here, when the wastewater containing ammonia is evaporated and concentrated, concentrated water containing salt and the like, and condensed water generated by agglomeration of the evaporated water are obtained. Since ammonia is mixed in the aggregated water, the ammonia is separated or decomposed and removed from the aggregated water in order to regenerate relatively clean and reusable water such as pure water. It is necessary to do. The important point is to prevent ammonia from returning to the evaporative concentrator.

Examples of the method for removing ammonia from the condensed water include an ammonia stripping method for physically removing ammonia. In this method, ammonia is removed from the aggregated water by using ammonium ions (NH ₄ ⁺ ) as ammonia gas (NH ₃ ) by increasing the pH of the aggregated water or increasing the liquid temperature. However, when the above ammonia stripping method is used, there is a problem that necessary facilities and apparatuses are increased in size, and a means for absorbing and decomposing ammonia gas that has become a gas is separately required.

  In the chlorination method, which is a method for removing ammonia from the condensed water, hypochlorous acid must be used to chlorinate (decompose) ammonia. Hypochlorous acid has a strong oxidizing power. However, there is a problem that the maximum care is required for the handling.

  When using the method of denitrification by biological treatment (biological denitrification method), the condensed water containing ammonia is insufficient for the concentration of salts containing trace elements necessary for biological treatment. There is a problem that is not suitable. When biologically treating the condensed water, it is necessary to increase the salt concentration by increasing the amount of chemical added. In this case, there is a problem of increasing the ion load when recovered as pure water. is there.

Furthermore, for example, Patent Document 1 proposes trapping ammonium ions contained in an aqueous solution by ion exchange treatment, but does not describe decomposition of ammonia. For example, Patent Document 2 describes ammonia. Has been disclosed that decomposes by supercritical water reaction with concentrated wastewater, but preparation and control of supercritical water is relatively difficult, supercritical water reactor must be used, construction of equipment There is a problem that costs and processing costs are high.
JP 2003-236564 A Japanese Patent Laid-Open No. 11-077089

  As described above, the conventional technology includes, in particular, wastewater containing ammonia generated in the recovery process of liquid crystal manufacturing plants and semiconductor manufacturing plants, further condensed water containing ammonia, regenerated waste liquid containing ammonia, and concentrated liquid containing ammonia. Since there was no suitable method for separating or decomposing and removing ammonia, the present inventors directly electrolyze the condensed water obtained by evaporating and concentrating waste water containing ammonia, and decompose and remove ammonia. The method was studied earnestly.

  However, when electrolyzing the condensed water directly, it is necessary to add a large amount of chemicals containing chlorine such as sodium chloride (NaCl) for electrolysis. Furthermore, when the water after electrolysis is reused as pure water, it is necessary to remove ions by ion exchange. However, since the ion load increases due to the addition of sodium chloride or the like, the required ion exchange apparatus becomes large. Furthermore, there is a problem that the amount of concentrated water (unloading liquid) obtained by the evaporation concentration increases, and the amount of final waste increases. In addition, since all of the condensed water is electrolyzed, there is a problem that the electrolyzer becomes large and power consumption increases.

  Therefore, the present invention is more reliable at low cost from wastewater containing ammonia generated in the recovery process of liquid crystal manufacturing plants and semiconductor manufacturing plants, as well as condensed water containing ammonia, recycled wastewater containing ammonia, and concentrated liquid containing ammonia. Another object of the present invention is to provide a method and apparatus for treating ammonia-containing water that can decompose and remove ammonia.

  More specifically, the present invention solves the above-mentioned problems caused by direct electrolysis of the wastewater containing ammonia, and uses less additives such as sodium chloride and suppresses an increase in ion load. Thus, it is possible to suppress an increase in the size of the ion exchange device, and in particular, it is possible to suppress an increase in the amount of concentrated water (unloading liquid) obtained by evaporating and concentrating the wastewater containing ammonia and an increase in power consumption in the electrolysis device. An object of the present invention is to provide a method and an apparatus for treating ammonia-containing water.

In order to achieve the above object, the present invention provides:
From waste water containing at least ammonia is discharged in the course of manufacturing liquid crystal or semiconductor, after obtaining the condensed water by evaporative concentration step C of evaporation, by applying an ion exchange treatment in the condensed water, the liquid to be treated or de Process liquid preparation step A for obtaining ionic water ;
An electrolysis process B for electrolyzing the process liquid discharged from the process liquid preparation process A to decompose and remove the ammonia to obtain a process waste liquid;
Equipped with,
Reusing the deionized water discharged from the liquid preparation step A in the liquid crystal or semiconductor manufacturing process ;
A method for treating ammonia-containing water is provided.

Here, the decomposition of ammonia in the present invention is a concept including converting ammonia into other forms such as nitrate ion, nitrite ion, nitrogen gas, nitrogen dioxide gas, nitrous oxide gas (N ₂ O), and the like. It is. In addition, about the ammonia component in this specification, what was adsorbed to the ion exchanger is referred to as “ammonium ion”, and what is contained in water is referred to as “ammonia”.

Further, the “drainage containing at least ammonia” in the present invention refers to, for example, wastewater (ammonia-containing water) generated in a recovery process of a liquid crystal manufacturing factory or a semiconductor manufacturing factory, as long as it contains at least ammonia and can further generate ammonia. It may contain a substance.
In the semiconductor manufacturing process, wafers are microfabricated using various chemicals, so that a solution containing various chemicals that have been used is discharged as waste water. For example, in a developing operation performed in a wafer photolithography process, the wafer or liquid crystal is processed with a processing solution containing (CH ₃ ) ₄ NOH (TMAH), so organic alkaline wastewater containing TMAH as a main component is discharged. Is done.

In the wafer cleaning process, the wafer is often cleaned with cleaning water containing NH ₄ OH, H ₂ O ₂ and H ₂ O, and waste water containing NH ₄ OH and H ₂ O ₂ is discharged.
Therefore, the “drainage containing at least ammonia” may contain at least one of TMAH, NH ₄ OH, MEA (monoethanolamine), H ₂ O _{2 and the} like that can generate ammonia in addition to ammonia. . Of course, in addition to the above, a substance that may be mixed in a recovery process of a liquid crystal manufacturing factory or a semiconductor manufacturing factory may be included.

The method for treating ammonia-containing water of the present invention is as follows.
Before the treatment liquid preparation step A, it comprises an evaporation concentration step C for evaporating and concentrating the waste water,
Wherein the liquid to be treated preparation step A, the Ru obtained liquid to be treated by performing an ion exchange treatment the condensed water obtained in the evaporative concentration step C.
According to such a configuration, ammonia can be collected in the condensed water by evaporation and concentration, so that ammonia can be decomposed and removed more reliably.

Further, the method for treating ammonia-containing water of the present invention is as follows.
After said electrolysis step B, it provided the evaporation step D of evaporation of the waste solution obtained in the electrolysis step B.
According to such a structure, the salt etc. which were left in the processing waste liquid after electrolytic treatment can be removed, and condensed water can be reused as pure water.

Furthermore, the method for treating ammonia-containing water of the present invention includes:
Before the treatment liquid preparation step A, it comprises an evaporation concentration step C for evaporating and concentrating the waste water,
After the electrolysis step B, it comprises an evaporation concentration step D for evaporating and concentrating the treatment waste liquid,
Wherein in the liquid to be treated preparation step A, the waste water, at least one of the condensed water obtained in the evaporative concentration step C obtained in condensed water and the evaporative concentration step D, applying an ion exchange treatment To obtain the liquid to be treated,
It is preferable to perform the evaporative concentration step C together with the evaporative concentration step D and evaporate and concentrate the wastewater together with the treated wastewater.

  According to such a configuration, ammonia can be collected in the condensed water by evaporation and concentration, and the ammonia remaining in the treatment waste liquid after the electrolytic treatment can be collected again in the condensed water. It can be removed and the circulation of ammonia can be prevented. In particular, the evaporation concentration process C and the evaporation concentration process D can be performed at the same timing with the same apparatus, which is effective.

Here, the ion exchange treatment includes an ion exchange step of obtaining ionized water by ion exchange of the waste water using an ion exchanger,
It is preferable to comprise an ion exchanger regeneration step in which the ion exchanger having adsorbed ammonium ions in the ion exchange step is washed with an acid to obtain a liquid to be treated containing a regeneration waste solution containing ammonia .

  In the ion exchanger regeneration step, sulfuric acid or hydrochloric acid can be used as the acid. It is preferable to use sulfuric acid from the viewpoint of suppressing supply of a chlorine component more than the necessary amount and preventing corrosion of the evaporative concentrator, which is particularly vulnerable to the chlorine component, and suppressing its life reduction. From the viewpoint of further reducing the power consumption and the amount of final waste, it is preferable to use hydrochloric acid.

However, reproduction waste liquid or Ranaru liquid to be treated the ion exchanger obtained by reproducing with sulfuric acid does not contain chlorine components. For this reason, before being subjected to the electrolysis step B, it is necessary to add a chemical (chlorine compound) containing chlorine or chlorine ions to the liquid to be treated. Examples of chemicals to be added include sodium chloride (NaCl), potassium chloride (KCl), and sodium hypochlorite (NaClO). However, as will be described later, it is preferable to minimize the amount of the chemical added in order to prevent internal corrosion of peripheral devices and evaporation concentrators.

Moreover, it is preferable to add an alkaline agent (for example, at least one selected from the group consisting of sodium hydroxide and potassium hydroxide) to the liquid to be treated before the electrolysis step B. According to this, the pH of the liquid to be treated can be reliably adjusted to a pH suitable for electrolysis.
It is also possible to produce pure water from the deionized water obtained in the treatment liquid preparation step A. According to this, water from which ammonia and salts have been reliably removed can be obtained.
In addition, when the purity of the deionized water obtained in the said ion exchange process is high, the said deionized water is also contained in the "pure water" here.

Furthermore, the present invention provides
An evaporative concentrator that obtains concentrated water and condensed water by pre-evaporating and condensing wastewater containing at least ammonia discharged in the liquid crystal or semiconductor manufacturing process ;
And obtained Ru ion exchanger the liquid to be treated or deionized water the condensed water by ion exchange with an ion exchanger,
An electrolysis apparatus for obtaining a treatment waste liquid by decomposing and removing the ammonia by electrolyzing a treated waste liquid containing the regenerated waste liquid or the concentrated liquid produced when regenerating the ion exchanger;
Equipped with,
The deionized water obtained in the ion exchange device has a configuration that is reused in the manufacturing process of the liquid crystal or semiconductor,
An apparatus for treating ammonia-containing water is provided.

The processing apparatus ammonia-containing water of the present invention comprises an evaporation device the draining beforehand evaporated obtaining a concentrated water and condensed water, the waste liquid obtained in the electrolytic device, with the drainage It evaporative concentration in the evaporative concentration apparatus.
Furthermore, it is preferable to provide a pure water device for producing pure water from deionized water obtained in the ion exchange device.
The “deionized water” in the present invention is a concept including ion-exchanged water (ion-treated water) obtained after ion-exchange treatment.

  According to the method and apparatus for treating ammonia-containing water according to the present invention, wastewater containing ammonia generated in the recovery process of a liquid crystal manufacturing factory or a semiconductor manufacturing factory, and further, condensed water containing ammonia and ammonia are produced. Ammonia can be decomposed and removed at low cost and more reliably from regenerated waste liquid containing ammonia and concentrated liquid containing ammonia, and the circulation of ammonia is more reliably performed in a treatment method and treatment apparatus for circulating ammonia-containing water. Can be prevented.

  In addition, according to the present invention, in particular, the conventional problems caused by direct electrolysis of the waste water containing ammonia are solved, the amount of sodium chloride used and the increase in ion load are small, and the increase in size of the ion exchange device is suppressed. The amount of concentrated water (unloaded liquid) obtained by evaporating and concentrating the wastewater containing ammonia and the power consumption in the electrolyzer can be suppressed, and ammonia can be decomposed and removed.

Hereinafter, preferred embodiments and reference embodiments of the present invention will be described with reference to the drawings. It should be noted that the present invention is not limited to these, and in the following description, the same or corresponding parts are denoted by the same reference numerals, and redundant description may be omitted.

[Form state of implementation]
FIG. 1 shows the configuration of an ammonia-containing water treatment apparatus (that is, an embodiment of the ammonia-containing water treatment apparatus according to the first embodiment) used for carrying out the first embodiment of the method for treating ammonia-containing water according to the present invention. It is a block diagram for demonstrating.

  As shown in FIG. 1, an ammonia-containing water treatment apparatus 1 according to the present embodiment includes an evaporative concentration apparatus 16 and an evaporative concentration apparatus that evaporate and concentrate wastewater containing at least ammonia to obtain concentrated water (unloading liquid) and condensed water. The flocculated water from 16 is ion-exchanged with an ion exchanger to obtain deionized water (ion-exchanged water), and the regenerated waste liquid generated when the ion exchanger is regenerated is electrolyzed. It includes an electrolysis device 20 that decomposes and removes ammonia contained in the regenerated waste liquid to obtain a treatment waste liquid, and includes a waste water collection device 14 and a pure water device 22 for collecting waste water containing at least ammonia from the clean room 12. Including.

The ammonia-containing water treatment method according to the present embodiment using the ammonia-containing water treatment apparatus,
(1) Evaporation concentration step C for evaporating and concentrating waste water containing at least ammonia;
(2) A treatment liquid preparation step A for obtaining a treatment liquid by subjecting the condensed water obtained in the evaporation concentration step C to an ion exchange treatment;
(3) Electrolysis step B of electrolyzing the liquid to be treated to decompose and remove the ammonia to obtain a treatment waste liquid;
(4) After the electrolysis step B, an evaporation concentration step D for evaporating and concentrating the treatment waste liquid is provided in the order of (1) to (4).

In the liquid preparation process A, the condensed water obtained in the evaporation and concentration process C and the condensed water obtained in the evaporation and concentration process D are subjected to ion exchange treatment, and the evaporation and concentration process C is evaporated. Performing together with the concentration step D, the waste water is evaporated and concentrated together with the treated waste water.
Here, the ion exchange treatment of the above (2) includes an ion exchange step in which the condensed water is ion-exchanged using an ion exchanger to obtain deionized water, and the ion exchange in which ammonium ions are adsorbed by the ion exchange step. An ion exchanger regeneration step in which the body is washed with an acid to obtain a liquid to be treated comprising a regeneration waste liquid containing ammonia.

Hereinafter, the present embodiment will be described in more detail.
In this embodiment, first, in a clean room 12 in a liquid crystal manufacturing factory or a semiconductor manufacturing factory, it is used in liquid crystal manufacturing or semiconductor manufacturing processes (for example, cleaning and etching of wafers), and wastewater containing ammonia (rinse drainage, scrubber drainage). Is discharged. Note that this waste water contains not only ammonia but also fluorine, for example.

The waste water is collected by the waste water collecting device 14, and the waste water from the waste water collecting device 14 is supplied to the evaporation concentrating device 16 and concentrated by evaporation (evaporation concentration step C).
In the wastewater recovery device 14, wastewater treatment such as biological treatment or reverse osmosis membrane treatment may be performed according to the type of wastewater. Further, the permeated water obtained by the reverse osmosis membrane treatment or the like may be returned to the pure water device.

The evaporative concentrator 16 is not particularly limited as long as it can heat and concentrate the waste water containing at least ammonia, and various types and systems can be used. For example, a multi-effect system, a multistage flash system, a falling liquid film system, and the like can be given. Any of these evaporative concentration apparatuses may be used, but it is preferable to select an optimal evaporative concentration apparatus depending on the properties of the waste water.
The concentrated water (unloading liquid) obtained by the evaporative concentration device 16 becomes waste, and the condensed water obtained by evaporating and concentrating the waste water is reused. Is supplied for further processing.

For example, in a facility where aggregated water is generated at 1000 m ³ / day, in order to electrolyze ammonia directly from the aggregated water, it is necessary to add a large amount of sodium chloride, for example, 250 mg / L (250 kg / day). If pure water is to be produced after electrolysis, the ionic load becomes large. On the other hand, in this Embodiment, the to-be-processed liquid is first prepared by ion-exchange-treating the said condensed water in the ion exchange apparatus 18 (to-be-processed liquid preparation process A).

  The ion exchange device 18 is not particularly limited as long as it has an ion exchanger such as an ion exchange resin and can remove ammonia contained in the condensed water, and various devices can be used. . Examples of the ion exchange apparatus 18 include an ion exchange tower filled with a conventionally known ion exchange resin.

In the ion exchanger 18 as described above, deionized water is obtained, and when the ion exchanger is washed and regenerated with an acid, a liquid to be treated consisting of a regenerated waste liquid is obtained. Ammonia is concentrated and expelled from the condensed water to the recycled waste liquid side. Although the deionized water can be used as it is depending on the application, it can also be used for the production of pure water in the pure water device 22 .

The pure water apparatus 22 for producing pure water from the deionized water is not particularly limited, and a conventionally known apparatus can be used. For example, a pure water apparatus or a reverse osmosis membrane apparatus including an ion exchange resin is included. And a pure water device equipped with an electric deionization device. In addition, about the waste_water | drain discharged | emitted at the time of pure water manufacture in a pure water apparatus, it is sent to the waste_water | drain collection | recovery apparatus 14 as needed.

Here, the design and operation of the ion exchange device 18 and regeneration by acid cleaning can be performed under various conditions as necessary. For example, the ammonia concentration of the regenerated waste liquid can be adjusted as appropriate.
The ion exchanger is regenerated by acid washing to obtain a regenerated waste liquid, and hydrochloric acid or sulfuric acid may be used as the acid for acid washing.

When hydrochloric acid is used as the acid for acid cleaning, the function as an oxidant and electrolyte is exhibited without adding sodium chloride or the like for electrolysis as described later.
On the other hand, the widely used hydrochloric acid solution has a low concentration of about 35%, the generation of hydrochloric acid vapor may corrode surrounding equipment, Since it is weak against ions, sulfuric acid may be used instead of hydrochloric acid (sulfuric acid regeneration). In particular, a widely used sulfuric acid solution has a high concentration and is preferable for transportation and storage. However, in this case, sodium chloride or the like needs to be added separately.

  In this embodiment, since hydrochloric acid is used as the acid for acid cleaning, it is not necessary to add sodium chloride or the like, and even when sulfuric acid is used as the acid for acid cleaning, it is added. Since the amount of sodium chloride to be used is small, the ion load is small, the amount of concentrated water (unloading liquid) obtained after evaporating and concentrating the treatment waste liquid obtained after electrolysis of the regenerated waste liquid is reduced, and the final waste Reduction and disposal costs can be reduced.

  However, it is preferable to add sodium hydroxide or the like to the recycled waste liquid before being supplied to the electrolysis apparatus 20 or before the electrolysis treatment in the electrolysis apparatus 20. This is because the pH of the regenerated waste liquid is preferably almost neutral (for example, 6 to 8) for the purpose of improving corrosion efficiency and reaction efficiency during electrolysis.

  On the other hand, when the treatment waste liquid obtained after electrolyzing the liquid to be treated composed of the regenerated waste liquid is evaporated and concentrated in the evaporation concentrator 16 (evaporation concentration step D), the pH of the treatment waste liquid is alkaline from the viewpoint of preventing apparatus corrosion. Since it is preferable (for example, pH 9-11), it is preferable to add alkaline agents, such as sodium hydroxide, to the said reproduction | regeneration waste liquid also from this point.

  As the electrolysis apparatus 20 for electrolyzing the liquid to be treated which is obtained from the regenerated waste liquid obtained by the ion exchange apparatus 18 (electrolysis step B), for example, a cathode, an anode, and a power supply apparatus for connecting the cathode and the anode are provided. A conventionally used electrolytic cell can be used, and the regenerated waste liquid is electrochemically oxidatively decomposed to generate a hypochlorite-based strong oxidizing substance, and the strong oxidizing substance generates the regenerated waste liquid. Electrolyzes the ammonia component.

The following reactions typically occur at the anode and cathode of the electrolysis apparatus 20 due to Cl- ions and water contained in the regenerated waste liquid.
Anode: 2H ₂ O-2e ⁻ → 4H ⁺ + O ₂
2Cl ⁻ → Cl ₂ + 2e ⁻
Cl ₂ + H ₂ O → HClO + HCl
Cathode: 2H ₂ O + 2e ⁻ → 2OH ⁻ + H ₂

At the anode, chlorine is generated, and further, the chlorine reacts with water to produce hypochlorous acid (HClO) having a strong oxidizing power. On the other hand, hydrogen is generated at the cathode by the decomposition of water. Ammonia contained in the recycled waste liquid is decomposed and removed by the following formula by hypochlorous acid generated at the anode.
2NH ₃ + 3HClO → N ₂ + 3HCl + 3H ₂ O
2NH ₃ + 3NaClO → N ₂ + 3NaCl + 3H ₂ O (alkaline)

  The electrolytic cell included in the electrolysis device 20 maintains electrolytic efficiency by applying a reverse voltage every certain period to remove substances adhering to the anode and the cathode, or by stopping the treatment and washing. Also good. The electrolytic treatment in the electrolytic device 20 may be continuous treatment or batch treatment. In addition, the electrolysis time, temperature, voltage, power amount (electric amount), treatment amount (residence time) and the like depend on the properties of the regenerated waste liquid, but the effect of the present invention can be obtained by selecting as appropriate. it can.

  As the anode and the cathode, conventional ones can be used. For example, the surface of the metal titanium plate is coated with a conductive ruthenium oxide, iridium oxide or platinum-based layer, or the surface of the metal titanium plate. Examples thereof include an electrode coated with a main layer of platinum or iridium oxide. A composite electrode including a base material made of conductive ceramic and a metal catalyst or an oxide catalyst added or dispersed in the base material can also be used.

  As described above, according to the present embodiment, the ion exchange apparatus 18 performs the ion exchange of the condensed water after the evaporation concentration in the evaporation concentration apparatus 16 for the wastewater containing ammonia generated in the recovery process of the liquid crystal manufacturing factory or the semiconductor manufacturing factory. Then, electrolysis is performed in the electrolysis apparatus 20. Therefore, it is not necessary to electrolyze the entire amount of waste water, so that the electrolysis equipment can be downsized.

  Moreover, since it is not necessary to add an additive etc. before ion-exchange of condensed water, the ion load concerning the ion exchange apparatus 18 becomes small, and a small ion exchange apparatus can be used. Furthermore, since the amount of additive can be reduced compared to the case where the entire amount is subjected to electrolytic treatment, the amount of concentrated salt contained in the concentrated water (unloading liquid) obtained by evaporation and concentration is reduced, and the final waste is reduced and the processing cost is reduced. Can be reduced.

[ Reference form 1 ]
FIG. 2 illustrates the configuration of the ammonia-containing water treatment apparatus (that is, the reference form 1 of the ammonia-containing water treatment apparatus of the present invention) used for carrying out the reference form 1 of the ammonia-containing water treatment method of the present invention. It is a block diagram for. The description of the same components as those in the above embodiment is omitted.

As shown in FIG. 2, the processing apparatus 1 of ammonium-containing water of the present reference embodiment, evaporative concentration apparatus 16 to obtain at least a waste water containing ammonia evaporated and concentrated water (out solution) and condensed water, evaporative concentration apparatus 16 A reverse osmosis membrane device 24a or an electric deionization device 24b for obtaining a treatment liquid comprising a concentrated liquid by subjecting the condensed water from the above to reverse osmosis membrane treatment or electric deionization treatment, and electrolyzing the treatment liquid And an electrolyzer 20 for decomposing and removing ammonia contained in the liquid to be treated to obtain a treatment waste liquid.

Processing method of ammonia-containing water according to this reference embodiment with the processing device of the ammonia-containing water,
(1) Evaporation concentration step C for evaporating and concentrating waste water containing at least ammonia;
(2) A treatment liquid preparation step A for obtaining a treatment liquid comprising a concentrated liquid by subjecting the condensed water obtained in the evaporation concentration step C to reverse osmosis membrane treatment or electric deionization treatment;
(3) Electrolysis step B of electrolyzing the liquid to be treated to decompose and remove the ammonia to obtain a treatment waste liquid;
(4) After the electrolysis step B, an evaporation concentration step D for evaporating and concentrating the treatment waste liquid is provided in the order of (1) to (4).

Below, this reference form is demonstrated in detail.
In this reference embodiment, first, in a clean room 12 in a liquid crystal manufacturing factory or a semiconductor manufacturing factory, it is used in liquid crystal manufacturing or semiconductor manufacturing processes (for example, cleaning and etching of wafers), and waste water containing ammonia (rinse waste water, scrubber waste water) is used. Discharged. Note that this waste water contains not only ammonia but also fluorine, for example.

The waste water is collected by the waste water collection device 14, and then supplied to the evaporation concentration device 16 to be evaporated and concentrated (evaporation concentration step C). Further, as in the first embodiment, the waste water recovery device 14 may perform waste water treatment such as biological treatment or reverse osmosis membrane treatment according to the type of waste water.
As the evaporation concentrating device 16, the same one as described in the first embodiment can be used.

Next, the condensed water obtained by evaporation and concentration is supplied to the reverse osmosis membrane device 24a or the electric deionization device 24b to obtain a liquid to be treated which is a concentrated liquid (processed water preparation step A).
Here, as the reverse osmosis membrane device 24a used for the reverse osmosis membrane treatment of (2) above, for example, ES20 manufactured by Nitto Denko Corporation, which is an ultra-low pressure spiral reverse osmosis membrane, or SUL manufactured by Toray Industries, Inc. -G20 or the like can be used.
Moreover, as the electrical deionization device 24b used for the electrical deionization process, for example, E-Demi manufactured by Shinko Environmental Solution Co., Ltd. can be used.

  Next, the liquid to be treated is supplied to the electrolysis apparatus 20. The liquid to be treated is electrolyzed in the electrolysis apparatus 20, and the ammonia is decomposed and removed to obtain a treatment waste liquid (electrolysis step B). After the electrolysis step B, the processing waste liquid is supplied to the evaporation concentrating device 16 and concentrated by evaporation (evaporation concentration step D). The electrolysis apparatus 20 and the evaporation concentrating apparatus 16 used here can be the same as those described in the first embodiment.

Also in this preferred embodiment, deionized water obtained in the reverse osmosis unit or an electrodeionization device, depending on the application may be used as it is, the production of pure water in the pure water device 22 as needed It can also be used.
Furthermore, concentrate (liquid to be treated) of Embodiment did not contain any amount of chlorine ions is small, or chlorine ions, chemicals separately containing chlorine or chloride ions for the electrolysis before electrolysis step B (e.g. Sodium chloride, potassium chloride or sodium hypochlorite) must be added.

According to this preferred embodiment as described above, the liquid crystal ammonia wastewater containing occurring in the recovery process of the manufacturing plant and semiconductor manufacturing plants, reverse osmosis membrane treatment or electric deionized reverse osmosis membrane treatment of each device 24a or electric de After performing in the ion device 24b, electrolysis is performed in the electrolytic device 20. Therefore, it is not necessary to electrolyze all of the waste water, so that the electrolysis equipment can be downsized.

  Further, since it is not necessary to add an additive before the drainage is subjected to reverse osmosis membrane treatment or electric deionization treatment, the load applied to the reverse osmosis membrane device 24a or the electric deionization device 24b is reduced, and a small-sized reverse osmosis is performed. A membrane device or an electrical deionization device can be used. Furthermore, since the amount of additive can be reduced compared to the case where the entire amount is subjected to electrolytic treatment, the amount of concentrated salt contained in the concentrated water (unloading liquid) obtained by evaporation and concentration is reduced, and the final waste is reduced and the processing cost is reduced. Can be reduced.

[ Reference form 2 ]
FIG. 3 illustrates the configuration of the ammonia-containing water treatment apparatus (that is, the reference form 2 of the ammonia-containing water treatment apparatus of the present invention) used to implement the reference form 2 of the method for treating ammonia-containing water of the present invention. It is a block diagram for. The description of the same components as those in the above embodiment and reference embodiments is omitted.

As shown in FIG. 3, the processing apparatus 1 of ammonium-containing water of the present reference embodiment, the waste water containing at least ammonia and ion exchange by the ion exchanger, the ion exchange device 18 to obtain the ion-exchanged water, the ion exchanger Electrolyzing a liquid to be treated, which is a recycle waste liquid generated during regeneration, decomposing and removing ammonia contained in the liquid to be treated, and obtaining an electrolyzed apparatus 20 for obtaining a treatment waste liquid, and concentrating by evaporating and concentrating the process waste liquid It includes an evaporating and concentrating device 16 for obtaining water (unloading liquid) and condensed water.
This reference form can be suitably used when only a part of the wastewater contains ammonia or contains ammonia at a high concentration.

Processing method of ammonia-containing water according to this reference embodiment with the processing device of the ammonia-containing water,
(1) A treatment liquid preparation step A for obtaining a treatment liquid by performing an ion exchange treatment on waste water containing at least ammonia;
(2) Electrolysis step B of electrolyzing the liquid to be treated to decompose and remove the ammonia to obtain a treatment waste liquid;
(3) After the electrolysis step B, an evaporation concentration step D for evaporating and concentrating the treatment waste liquid is provided in the order of (1) to (3).

  Here, the ion exchange treatment of the above (1) includes an ion exchange step of ion-exchanging the waste water using an ion exchanger to obtain deionized water, and the ion exchanger adsorbing ammonium ions by the ion exchange step. And an ion exchanger regeneration step of obtaining a liquid to be treated comprising a regeneration waste solution containing ammonia.

Below, this reference form is demonstrated in detail.
In this reference embodiment, first, in a clean room 12 in a liquid crystal manufacturing factory or a semiconductor manufacturing factory, it is used in liquid crystal manufacturing or semiconductor manufacturing processes (for example, cleaning and etching of wafers), and waste water containing ammonia (rinse waste water, scrubber waste water) is used. Discharged. Note that this waste water contains not only ammonia but also fluorine, for example.

  The waste water is supplied to the ion exchange device 18 in the waste water collecting device 14. As the ion exchange device 18, the same device as that described in the first embodiment can be used. Ion exchange water is obtained by ion exchange treatment of the waste water using an ion exchanger, the ion exchanger adsorbing ammonium ions by the ion exchange is washed with an acid, and a liquid to be treated comprising a recycled waste liquid containing ammonia Is obtained (processed liquid preparation step A).

The deionized water obtained by ion exchange can be used as it is depending on the application, and can be returned to the pure water device 22 to be used for producing pure water.
In addition, when hydrochloric acid is not used for regeneration, since the regeneration waste solution containing ammonia does not contain chlorine, a chemical containing chlorine or chlorine ions for electrolysis before the electrolysis step B (for example, sodium chloride, chloride) Potassium or sodium hypochlorite) must be added.

Next, the liquid to be treated is supplied to the electrolysis apparatus 20 and electrolyzed, and ammonia in the liquid to be treated is decomposed and removed to obtain a treatment waste liquid (electrolysis step B). After the electrolysis step B, the processing waste liquid is supplied to the evaporation concentrating device 16 and evaporated (concentration step D). Even electrolytic device 20 and the evaporation device 16 used here may be the same as those described in the form status of the above embodiment.

According to this reference embodiment as described above, after the ion exchange is performed in the ion exchange device 18 for the wastewater containing ammonia generated in the recovery process of the liquid crystal manufacturing factory or the semiconductor manufacturing factory, the electrolysis is performed in the electrolysis apparatus 20. Therefore, it is not necessary to electrolyze the entire amount of waste water, so that the electrolysis equipment can be downsized.

  Moreover, since it is not necessary to add an additive before ion-exchanging the said waste_water | drain, the ion load concerning the ion exchange apparatus 18 becomes small, and a small ion exchange apparatus can be used. Furthermore, since the amount of additive can be reduced compared to the case where the entire amount is subjected to electrolytic treatment, the amount of concentrated salt contained in the concentrated water (unloading liquid) obtained by evaporation and concentration is reduced, and the final waste is reduced and the processing cost is reduced. Can be reduced.

[ Reference form 3 ]
FIG. 4 illustrates the configuration of the ammonia-containing water treatment apparatus (that is, the reference form 3 of the ammonia-containing water treatment apparatus of the present invention) used to implement the reference form 3 of the ammonia-containing water treatment method of the present invention. It is a block diagram for. The description of the same components as those in the above embodiment or reference embodiment is omitted.

As shown in FIG. 4, the ammonia-containing water treatment apparatus 1 of the present reference embodiment is the same as that of the reference embodiment 2 except that a reverse osmosis membrane apparatus 24 a or an electric deionization apparatus 24 b is used instead of the ion exchange apparatus 18. It is the same as the treatment apparatus for ammonia-containing water.

That is, the processing apparatus 1 of ammonium-containing water of the present reference embodiment, drain the reverse osmosis membrane treatment or electric deionized treated reverse osmosis membrane to obtain a concentrated solution by device 24a or electrodeionization device 24b containing at least ammonia, An electrolysis device 20 that electrolyzes a liquid to be treated, which is a concentrated liquid obtained in the reverse osmosis membrane device 24a or the electric deionization device 24b, to decompose and remove ammonia contained in the liquid to be treated to obtain a treatment waste liquid, and It includes an evaporation concentrating device 16 that obtains concentrated water (unloading liquid) and condensed water by evaporating and concentrating the treatment waste liquid.
This reference form can also be used suitably when only a part of the wastewater contains ammonia or contains ammonia at a high concentration, as in the case of reference form 2 .

Processing method of ammonia-containing water according to this reference embodiment with the processing device of the ammonia-containing water,
(1) A treatment liquid preparation step A for obtaining a treatment liquid comprising a concentrated liquid by subjecting at least ammonia-containing wastewater to reverse osmosis membrane treatment or electric deionization treatment;
(2) Electrolysis step B of electrolyzing the liquid to be treated to decompose and remove the ammonia to obtain a treatment waste liquid;
(3) After the electrolysis step B, an evaporation concentration step D for evaporating and concentrating the treatment waste liquid is provided in the order of (1) to (3).

Below, this reference form is demonstrated in detail.
In this reference embodiment, first, in a clean room 12 in a liquid crystal manufacturing factory or a semiconductor manufacturing factory, it is used in liquid crystal manufacturing or semiconductor manufacturing processes (for example, cleaning and etching of wafers), and waste water containing ammonia (rinse waste water, scrubber waste water) is used. Discharged. Note that this waste water contains not only ammonia but also fluorine, for example.

The waste water is supplied to the reverse osmosis membrane device 24a or the electrical deionization device 24b in the waste water collecting device 14. Here, as the reverse osmosis membrane device 24a and the electrical deionization device 24b, those described in the above-mentioned reference embodiment 1 can be used.
By subjecting the waste water to reverse osmosis membrane treatment or electric deionization treatment, a liquid to be treated comprising a concentrated liquid is obtained (treatment liquid preparation step A).

Also in this reference form, the deionized water obtained by the to-be-processed liquid preparation process A can be used as it is depending on a use, and can also be returned to the pure water apparatus 22 and used for manufacture of a pure water.
In addition, since the concentrated solution containing ammonia has a small amount of chlorine or chlorine ions or is not contained, a chemical containing chlorine or chlorine ions separately for electrolysis (for example, sodium chloride) before the electrolysis step B , Potassium chloride or sodium hypochlorite).

Next, the liquid to be treated is supplied to the electrolysis apparatus 20 and electrolyzed, and ammonia in the liquid to be treated is decomposed and removed to obtain a treatment waste liquid (electrolysis step B). After the electrolysis step B, the processing waste liquid is supplied to the evaporation concentrating device 16 and concentrated by evaporation (evaporation concentration step D).
As the electrolysis apparatus 20 and the evaporation concentration apparatus 16 used here, the same ones as those described in the above embodiment can be used.

Above, such as, according to this preferred embodiment, a liquid crystal manufacturing plant and semiconductor wastewater containing ammonia occurring in the recovery process of the manufacturing plant, the reverse osmosis membrane treatment or reverse osmosis membrane electrodeionization process each device 24a or electric After performing in the deionization apparatus 24b, electrolysis is performed in the electrolysis apparatus 20. Therefore, since it is not necessary to electrolyze the entire amount of waste water, the electrolysis equipment can be downsized.

  Further, since it is not necessary to add an additive before the drainage is subjected to reverse osmosis membrane treatment or electric deionization treatment, the load applied to the reverse osmosis membrane device 24a or the electric deionization device 24b is reduced, and a small-sized reverse osmosis is performed. A membrane device or an electrical deionization device can be used. Furthermore, since the amount of additive can be reduced compared to the case where the entire amount is subjected to electrolytic treatment, the amount of concentrated salt contained in the concentrated water (unloading liquid) obtained by evaporation and concentration is reduced, and the final waste is reduced and the processing cost is reduced. Can be reduced.

As mentioned above, although typical embodiment and reference form of this invention were described, this invention is not limited only to these. For example, when components other than ammonia (for example, IPA or DMSO) are contained in the condensed water, devices such as a UV oxidation device, biological activated carbon, and activated carbon adsorption tower may be separately provided in front of the ion exchange device 18 or in the waste water collection device 14. Good.
Even if nitrate nitrogen or nitrite nitrogen is generated by the decomposition of ammonia by electrolytic treatment, the treated water after electrolysis is evaporated and concentrated in the present invention. Nitrite nitrogen is removed as concentrated water and discharged from outside the system.

  Below, the Example and comparative example which were performed in order to confirm the effect of the processing method and processing apparatus of the ammonia containing water of this invention mentioned above are described. In addition, this invention is not limited only to a following example.

<Example>
In this example, the ammonia-containing water treatment method of the present invention was performed using the ammonia-containing water treatment apparatus of the present invention having the configuration shown in FIG.
First, wastewater from the clean room 14 of the liquid crystal manufacturing plant is collected by the wastewater collection device 14 and treated by “biological treatment device + microfiltration membrane device (MF membrane device) + reverse osmosis membrane device (RO membrane device)”. The waste water containing the concentrated liquid (drainage containing ammonia) obtained by this reverse osmosis membrane device was supplied to the evaporation concentration device 16 to perform the evaporation concentration process (evaporation concentration step).
Here, the ammonia ion concentration in the waste water to the evaporative concentration device 16 was 15 mg / L, and the supply amount was 1055 m ³ / day. The ammonia ion concentration of the condensed water obtained from the evaporating and concentrating device 16 was 15 mg / L, and the generation amount was 1000 m ³ / day. The obtained concentrated water (discharged water) 55 m ³ / day was discharged to the outside.

Next, the ion-exchange resin (cation exchange resin) is filled with 5 m ^3, and the condensed water is supplied to the ion-exchange apparatus 18 having a configuration in which the superficial velocity {SV = (treatment amount / resin amount)} is 8.3 h ^−1. Then, deionized water was obtained by ion exchange (ion exchange step). The obtained ion exchange water was supplied to the pure water device 22.
In addition, the ion exchange resin used in the ion exchange apparatus 18 is washed once every 3 to 7 days with 1.5 eq of acid with respect to 1 L of the ion exchange resin, and the ammonia adsorbed on the ion exchange resin is removed. Removal and regeneration waste liquid containing the ammonia was obtained (ion exchanger regeneration step C).
At this time, the ammonia concentration of the obtained recycling waste liquid was 1730 mg / L, and the generation amount was 8.7 m ³ / day.

The regenerated waste liquid contained hydrochloric acid in an amount of 74.3 kg / day by acid washing as described above. Then, while supplying the regenerated waste liquid to the electrolyzer 20, sodium hydroxide was added to the regenerated waste liquid in an amount of 81.4 kg / day for neutralization.
Thus, the regenerated waste liquid containing hydrochloric acid and sodium hydroxide is introduced into the electrolysis apparatus 20 including the electrolytic cell including the anode and the cathode in which the surface of the metal titanium plate is coated with the iridium oxide layer, and the regenerated waste liquid is 8.7 m ^3. Was electrolyzed in an electrolytic cell under the condition of an electric power of 60 kWh / m ³ (electrolysis step).

Here, the treatment waste liquid obtained by electrolytic treatment of the regenerated waste liquid contained sodium chloride at a concentration of 13700 mg / L (119 kg / day). Such processing waste liquid was supplied to the evaporative concentration apparatus 16 and evaporatively concentrated with the waste water a.
At this time, the increase amount of the concentrated water (unloading liquid) in the evaporative concentration apparatus 16 accompanying the treatment of the condensed water as described above was 0.6 m ³ / day. Moreover, the power consumption of the electrolyzer 16 was 520 kWh / day.

《 Reference example》
Oite to the above embodiment, as in the case of hydrochloric acid wash was carried out acid washing with sulfuric acid in place cleaning of hydrochloric acid ion-exchange resin, to obtain a playback waste 8.7 m ³ / day of ammonia concentration 1730mg / L It was.
Since the regenerated waste liquid contained 99.5 kg / day of sulfuric acid by acid washing, 81.2 kg / day of sodium hydroxide was added for neutralization while supplying the regenerated waste liquid to the electrolyzer 20. Further, 77.4 kg / day of sodium chloride was added for electrolysis. This recycled waste liquid was introduced into the same electrolysis apparatus 20 as in Example 1, and the recycled waste liquid 8.7 m ³ was subjected to electrolytic treatment in an electrolytic cell under the condition of an electric power of 100 kWh / m ³ .

Here, the waste treatment liquid obtained by electrolytic treatment of the regenerated waste liquid contains sodium chloride at a concentration of 8900 mg / L (77.4 kg / day), and sodium sulfate at a concentration of 16600 mg / L (144 kg / day). Was included. Such processing waste liquid was supplied to the evaporative concentration apparatus 16 and evaporatively concentrated with the waste water a.
At this time, the increase amount of the concentrated water (unloading liquid) in the evaporation concentrator 16 accompanying the treatment of the condensed water as described above was 1.1 m ³ / day. Moreover, the power consumption of the electrolyzer 16 was 870 kWh / day.

《Comparative example》
In this comparative example, wastewater containing ammonia recovered in the clean room 14 of the liquid crystal manufacturing factory was treated using a treatment apparatus having the configuration shown in FIG.
FIG. 5 is a diagram showing a configuration of the ammonia-containing water treatment apparatus 100 used in this comparative example. The configuration of the devices other than the ion exchange device 18 and the electrolysis device 20 was the same as in the above example .

  The treatment apparatus 100 shown in FIG. 5 sequentially includes a wastewater recovery apparatus 14 that recovers wastewater containing at least ammonia, an evaporation concentration apparatus 16 that obtains condensed water and concentrated water by evaporation and concentration, and the condensed water from the evaporation concentration apparatus 16. Electrolysis device 20 that directly electrolyzes and decomposes and removes ammonia contained in the condensed water to obtain treated water, ion exchange device 18 that obtains deionized water by ion exchange of the treated water (cation exchange resin tower 18b and anion) Including two exchange resin towers 18c).

First, wastewater containing ammonia recovered in the wastewater recovery device 14 (ammonia concentration: 15 mg / L) was supplied to the evaporation concentration device 16 using the treatment device 100 as described above, and an evaporation concentration process was performed (evaporation concentration step). ). Subsequently, the condensed water was introduced into the electrolysis apparatus 20 and electrolysis was performed under the condition of electric power of 6 kWh / m ³ (electrolysis process).
However, in this comparative example, in order to directly electrolyze the aggregated water, 250 mg / L (250 kg / day) of sodium chloride was added to the aggregated water before being supplied to the electrolysis device 16.

In order to remove 250 kg / day of sodium chloride from the treated water obtained by the electrolyzer 20, deionized water was obtained by ion exchange of the treated water in the ion exchanger 18 (ion exchange step).
However, as the ion exchange device 18, a device composed of two towers of a cation exchange resin tower 18 b and an anion exchange resin tower 18 c was used. The cation exchange resin tower 18b was filled with 6.5 m ^{3 of} cation exchange resin, and the anion exchange resin tower 18c was filled with 5.5 m ^{3 of} weak anion exchange resin.
Treated water electrolysis device 20, these cation exchange resin tower 18b and the anion exchange resin column 18c, respectively and passed through at a superficial velocity 6.4H ^-1 and 7.6h ^-1.

Further, the ion exchanger (ion exchange resin) used in the cation exchange resin tower 18b and the anion exchange resin tower 18c of the ion exchange apparatus 18 is obtained using sulfuric acid (468 kg / day) and sodium hydroxide (382 kg / day). Washing was performed to remove sodium ions and chlorine ions adsorbed on the ion exchange resin, and a regeneration waste liquid containing them was obtained (ion exchanger regeneration step).
Sodium chloride and sodium sulfate contained in the regeneration waste liquid discharged from the ion exchange device 18 were 928 kg / day.

The regenerated waste liquid obtained by the above washing was supplied to the evaporative concentration device 16 and subjected to evaporative concentration treatment together with the waste water. At this time, it was necessary to evaporate and concentrate the regenerated waste liquid 53 m ³ / day from the ion exchange device 18 in the evaporative concentration device 16. Concentrated water in the evaporative concentrator 16 (discharged liquid, 20%) accompanying the treatment of the condensed water as described above increases to 4.6 m ³ / day, and the amount of the processing liquid in the evaporative concentrator 16 is 53 m ^3. / Day increased, and the evaporation concentrator 16 became large. Moreover, the power consumption of the electrolyzer 20 was 6000 kWh / day.
Here, the chemicals, wastes, and apparatuses required in the above Examples , Reference Examples and Comparative Examples are shown in Table 1 in comparison.

  As can be seen from Table 1, according to the method and apparatus for treating ammonia-containing water of the examples of the present invention, the following effects were obtained on the assumption that the condensed water was recovered into pure water raw water. (1) When electrolytic treatment is performed by adding sodium chloride to condensed water as in the comparative example, a cation exchange resin tower and an anion exchange resin tower are required to recover the treated water as pure water raw water. According to the example, it was only necessary to install a cation exchange resin tower for ion exchange before adding sodium chloride. (2) In the example, the amount of waste related to this treatment can be reduced to 1/4 to 1/7 as compared with the comparative example, and the final waste and the disposal cost can be reduced. (3) In the example, compared with the comparative example, the power consumption of the electrolyzer could be reduced to about 1/7 to 1/11.

That is, in the above comparative example, not only the amount of NaCl used is increased, but also NaCl is removed by ion exchange, so the amount of use of this regeneration NaOH and H ₂ SO ₄ is increased. However, in the embodiment of the present invention, this disadvantage can be avoided.

  According to the method and apparatus for treating ammonia-containing water according to the present invention, wastewater containing ammonia generated in the recovery process of a liquid crystal manufacturing factory or a semiconductor manufacturing factory, and further, condensed water containing ammonia and ammonia are produced. Ammonia can be decomposed and removed at low cost and more reliably from regenerated waste liquid containing ammonia and concentrated liquid containing ammonia, and the circulation of ammonia is more reliably performed in a treatment method and treatment apparatus for circulating ammonia-containing water. Can be prevented.

In addition, according to the present invention, the conventional problem due to direct electrolysis of the wastewater containing ammonia in particular is solved, and an increase in ion load due to addition of sodium chloride or the like is suppressed, so that installation of an anion exchange resin tower is unnecessary. In addition, it is possible to suppress the increase in the amount of concentrated water (unloading liquid) obtained by evaporating and concentrating the wastewater containing ammonia and the power consumption in the electrolysis apparatus, and to decompose and remove ammonia.
Therefore, the method and apparatus for treating ammonia-containing water of the present invention can be suitably used in a recovery process of a liquid crystal manufacturing factory or a semiconductor manufacturing factory.

It is a block diagram including the structure of Embodiment 1 of the processing apparatus of ammonia containing water of this invention used in order to implement Embodiment 1 of the processing method of ammonia containing water of this invention. It is a block diagram including the structure of Embodiment 2 of the processing apparatus of the ammonia containing water of this invention used in order to implement Embodiment 2 of the processing method of the ammonia containing water of this invention. It is a block diagram including the structure of Embodiment 3 of the ammonia containing water processing apparatus of this invention used in order to implement Embodiment 3 of the processing method of ammonia containing water of this invention. It is a block diagram including the structure of Embodiment 4 of the processing apparatus of the ammonia containing water of this invention used in order to implement Embodiment 4 of the processing method of the ammonia containing water of this invention. It is a block diagram including the structure of the processing apparatus of the ammonia containing water used in the comparative example of this invention.

DESCRIPTION OF SYMBOLS 10,100 ... Processing apparatus 14 of ammonia containing water ... Clean room 16 ... Evaporation concentration apparatus 18 ... Ion exchange apparatus 18a ... Reverse osmosis membrane apparatus 18b ... Cation exchange resin tower 18b
18c ... anion exchange resin tower 18c
DESCRIPTION OF SYMBOLS 20 ... Electrolysis apparatus 22 ... Pure water apparatus 24a ... Reverse osmosis membrane apparatus 24b ... Electric deionization apparatus

Claims (2)

After obtaining condensed water by evaporative concentration step C for evaporating and concentrating from waste water containing at least ammonia discharged in the liquid crystal or semiconductor manufacturing process, the aggregated water is subjected to ion exchange treatment, whereby a liquid to be treated or deionized Processed liquid preparation step A for obtaining water;
An electrolysis process B for electrolyzing the process liquid discharged from the process liquid preparation process A to decompose and remove the ammonia to obtain a process waste liquid;
Comprising
Reusing the deionized water discharged from the liquid preparation process A in the liquid crystal or semiconductor manufacturing process ,
After the electrolysis step B, comprising an evaporation concentration step D for evaporating and concentrating the treatment waste liquid obtained in the electrolysis step B ;
A method for treating ammonia-containing water. An evaporative concentrator that obtains concentrated water and condensed water by pre-evaporating and condensing wastewater containing at least ammonia discharged in the liquid crystal or semiconductor manufacturing process;
An ion exchange device that obtains deionized water by ion exchange of the condensed water using an ion exchanger;
An electrolytic apparatus for obtaining a treatment waste liquid by electrolyzing a liquid to be treated ( regeneration waste liquid ) generated when the ion exchanger is regenerated to decompose and remove the ammonia;
Comprising
The deionized water obtained in the ion exchange device has a configuration that is reused in the manufacturing process of the liquid crystal or semiconductor,
Processing waste liquid obtained in the electrolyzer, and evaporating and concentrating in the evaporative concentration apparatus together with the waste water
A device for treating ammonia-containing water.

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