JP2011173032A - Method and apparatus for treating thiourea-containing water - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To recover thiourea, which is a valuable substance, with high purity from thiourea-containing water while reducing the capacity of equipment for desalination treatment of the thiourea-containing water. <P>SOLUTION: The thiourea-containing water is concentrated by means of a reverse osmosis membrane which thiourea does not permeate, and the thiourea-containing water which has been thus concentrated by means of the reverse osmosis membrane which thiourea does not permeate is subjected to the desalination treatment to remove ionic substances other than thiourea, which are contained in the thiourea-containing water, and to recover thiourea contained in the thiourea-containing water. Alternatively, the thiourea-containing water is concentrated by means of an evaporative concentration apparatus, and the thiourea-containing water which has been thus concentrated is subjected to the desalination treatment to remove the ionic substances other than thiourea, which are contained in the thiourea-containing water, and to recover thiourea contained in the thiourea-containing water. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a method and apparatus for treating thiourea-containing water, and more particularly to a method and apparatus for treating thiourea-containing water that can recover valuable thiourea from thiourea-containing water.

  Specifically, the present invention relates to thiourea-containing water capable of recovering thiourea from thiourea-containing wastewater such as titanium oxide photocatalyst production wastewater, low hydrogen overvoltage cathode production wastewater, plating wastewater, chemical cleaning wastewater, and the like. The present invention relates to a processing method and apparatus.

  For example, Non-Patent Document 1 (“Consisional Chemical Assessment Document”, World Health Organization International Chemical Safety Program (IPCS UNEP // ILO // WHO), 2003, Vol. 49, Thiourea. On page 5 of (Thiourea), thiourea “is resistant to hydrolysis in water and direct photolysis in water and air and undergoes photochemical oxidation by hydroxyl radicals in the atmosphere ( (Calculated half-life is 2.4 hours.) Biodegradation of this substance is considered to be carried out by an acclimatized microflora only after a long acclimatization period and is therefore not suitable for biological or abiotic removal. Under certain conditions, thiourea may be present in surface water and sediment over time. ”And“ based on studies conducted primarily in laboratory animals, the main health adverse effects associated with thiourea exposure are thyroid function inhibition, but the lung, liver, hematopoietic system, and kidneys There is also a description of the effect: Thiourea causes pulmonary edema associated with changes in lung permeability. Also, on page 6 of Non-Patent Document 1, for thiourea, “According to the reliable test results available for toxicity to various aquatic organisms, thiourea is moderately to highly toxic in the aquatic environment. It can be classified ".

  Non-Patent Document 2 ("Chemical Substance Safety Data Sheet", Invitrogen Corporation, July 19, 2005, name of chemical substances, thiourea, item 3 summary of hazards) "Classification name Other toxic substances", "Dangerous flammability", "Harmology Irritating to skin, eyes, mucous membranes, etc. Harmful if accidentally swallowed or exposed. Serious to health by prolonged exposure. "There is a risk of causing damage" and "Environmental effects: Strongly toxic to aquatic organisms. Chemical substances judged to be indegradable (chemical substances specified by the Chemical Substances Control Law), concentrated in the body of seafood Chemical substances judged to be low (Ministry of International Trade and Industry announcement) ”are described.

  Furthermore, in paragraph [0044] of Patent Document 1 (Japanese Patent Application Laid-Open No. 2005-319423), a mixture containing thiourea and the like is formed, the mixture is fired, and the fired product obtained is pulverized, washed, and dried. It is described that a titanium oxide photocatalyst can be obtained by doing so. By the way, Patent Document 1 does not describe how to treat the titanium oxide photocatalyst production wastewater containing thiourea used in the production of the titanium oxide photocatalyst.

  Further, in the scope of claims of Patent Document 2 (Japanese Patent Laid-Open No. 60-29487), a cathode base material using a plating bath in which carbonaceous fine particles are dispersed and a nickel-based metal component as a plating metal is used. A method for producing a low hydrogen overvoltage cathode is described in which electroplating is performed on the surface and an easily detached plating layer formed on the surface is removed. Further, Patent Document 2 describes that after removing a plating layer that is easily detached after plating, reinforcing plating of nickel-sulfur plating is performed on the plating layer. It is described that the plating is electroplated by adding thiourea or the like to the plating bath. By the way, Patent Document 2 does not describe how to treat the low hydrogen overvoltage cathode production wastewater containing thiourea used for the production of the low hydrogen overvoltage cathode.

  Further, in Patent Document 3 (Japanese Patent Laid-Open No. 2006-104500), a material to be plated is immersed in a neutral or weakly basic pretreatment liquid containing a sulfur complexing agent and not containing an acid. An electroless tin plating method is described in which electroless plating is performed on an object to be plated using an electroless tin plating solution containing a soluble stannous salt, an acid and a sulfur complexing agent. Patent Document 3 describes thioureas as examples of the sulfur complexing agent contained in the pretreatment liquid. By the way, Patent Document 3 does not describe how to treat plating wastewater containing thioureas used in electroless tin plating.

  Further, Patent Document 4 (Japanese Patent Application Laid-Open No. 2005-290444) describes a gold electrolytic stripper that can remove a base layer for forming a bump without greatly deforming the shape of the bump electrode. Patent Document 4 describes that the gold electrolytic stripper contains thiourea. By the way, Patent Document 4 does not describe how to treat chemical cleaning wastewater containing thiourea used for gold electrolytic stripping.

JP 2005-319423 A JP-A-60-29487 JP 2006-104500 A JP 2005-290444 A

"Concise International Chemical Document, World Health Organization International Chemical Safety Program (IPCS UNEP // ILO // WHO), 2003, Vol. 49, Thiourea “Chemical Substance Safety Data Sheet”, Invitrogen Corporation, July 19, 2005, Name of Chemical Substances, Thiourea, Item 3 Hazard Summary

  As described in Non-Patent Documents 1 and 2, thiourea is toxic not only to aquatic organisms but also to terrestrial animals. Therefore, thiourea-containing water as described in Patent Documents 1 to 4 is used. It cannot be discharged as wastewater. However, thiourea is a substance that interferes with nitrogen removal (nitrification / denitrification) and is difficult to be treated with aerobic organisms, and requires sufficient training and is difficult to perform stable treatment. Therefore, conventionally, when processing thiourea-containing water as described in Patent Documents 1 to 4, it has been necessary to concentrate, incinerate, and dispose of it with great cost.

  On the other hand, since thiourea contained in thiourea-containing water is a valuable resource, the thiourea contained in the thiourea-containing water is not disposed of at a high cost. It can be said that recovery is a social need.

  In view of this point, as a result of intensive studies, the present inventor conducted thiourea contained in the thiourea-containing water when the thiourea-containing water was subjected to a desalting treatment or an adsorption treatment with a hydrophobic adsorbent. In addition, the present inventors have found that thiourea contained in thiourea-containing water can be concentrated not only by evaporation but also by a reverse osmosis membrane having a high organic matter rejection rate (specifically, a reverse osmosis membrane through which thiourea does not permeate).

  Specifically, as a result of earnest research, the present inventor has performed a desalting treatment load when the desalting treatment of thiourea-containing water is performed before the concentration treatment of thiourea-containing water. It has been found that when the capacity of the salt treatment facility is insufficient, impurities (salts) that are not sufficiently removed by the desalting treatment may be recovered together with thiourea.

  That is, an object of the present invention is to provide a method and apparatus for treating thiourea-containing water that can recover thiourea, which is a valuable material, from thiourea-containing water.

  Specifically, the present invention relates to a treatment of thiourea-containing water that can recover thiourea, which is a valuable resource, from thiourea-containing water with high purity while reducing the capacity of the desalination treatment facility for thiourea-containing water. It is an object to provide a method and apparatus.

  In the method for treating thiourea-containing water according to claim 1, the thiourea-containing water is concentrated by a reverse osmosis membrane through which thiourea does not permeate. Furthermore, ionic substances other than thiourea contained in the thiourea-containing water are removed by desalting the thiourea-containing water after being concentrated by the reverse osmosis membrane through which thiourea does not permeate. The thiourea contained in is recovered.

  Therefore, according to the method for treating thiourea-containing water described in claim 1, thiourea, which is a valuable material, can be recovered from the thiourea-containing water. Further, the amount of waste can be reduced as compared with the case where the thiourea-containing water is disposed of without the thiourea being recovered. Specifically, according to the method for treating thiourea-containing water according to claim 1, the thiourea-containing water is more hydrated than when the thiourea-containing water is desalted before being concentrated by a reverse osmosis membrane through which thiourea does not permeate. The capacity of the desalination facility for urea-containing water can be reduced. Furthermore, according to the method for treating thiourea-containing water according to claim 1, when the thiourea-containing water is desalted before being concentrated by the reverse osmosis membrane that does not allow thiourea to permeate, The risk of impurities being contained in the recovered thiourea can be reduced as the capacity of the desalting facility is insufficient. That is, according to the method for treating thiourea-containing water according to claim 1, thiourea, which is a valuable material, is purified from thiourea-containing water with high purity while reducing the capacity of the desalination treatment facility for thiourea-containing water. It can be recovered.

  In the method for treating thiourea-containing water according to claim 2, the thiourea-containing water is concentrated by the evaporating and concentrating device. Furthermore, by desalting the thiourea-containing water after being concentrated by the evaporation concentrator, ionic substances other than thiourea contained in the thiourea-containing water are removed, and the thiourea contained in the thiourea-containing water Is recovered.

  Therefore, according to the method for treating thiourea-containing water according to claim 2, valuable thiourea can be recovered from the thiourea-containing water. Further, the amount of waste can be reduced as compared with the case where the thiourea-containing water is disposed of without the thiourea being recovered. Specifically, according to the method for treating thiourea-containing water according to claim 2, the thiourea-containing water is removed more than when the thiourea-containing water is desalted before being concentrated by the evaporative concentration apparatus. The capacity of the salt treatment facility can be reduced. Furthermore, according to the method for treating thiourea-containing water according to claim 2, when the thiourea-containing water is desalted before being concentrated by the evaporating and concentrating device, the thiourea-containing water is desalted. The risk of impurities being contained in the recovered thiourea can be reduced as the capacity of is insufficient. That is, according to the method for treating thiourea-containing water according to claim 2, while reducing the capacity of the desalination treatment facility for thiourea-containing water, valuable thiourea is purified from thiourea-containing water with high purity. It can be recovered.

  In the method for treating thiourea-containing water according to claim 3, for example, an ion exchange resin such as 2B3T type or MIXBED type, an electrical desalination apparatus, a reverse osmosis membrane through which thiourea permeates, or a combination thereof Thus, ionic substances other than thiourea contained in the thiourea-containing water are removed.

  In the method for treating thiourea-containing water according to claim 4, before the thiourea-containing water is concentrated by the reverse osmosis membrane through which thiourea does not permeate, precipitation, filtration, a hydrophobic adsorbent, or a combination thereof. Impurities other than thiourea contained in the thiourea-containing water are removed. Therefore, according to the method for treating thiourea-containing water according to claim 4, before the thiourea-containing water is concentrated by the reverse osmosis membrane through which thiourea does not permeate, the thiourea-containing water is contained by precipitation, filtration or a hydrophobic adsorbent. Compared with the case where impurities other than thiourea contained in water are not removed, the content of impurities other than thiourea contained in the recovered thiourea can be reduced.

  In the method for treating thiourea-containing water according to claim 5, the thiourea-containing water is obtained by precipitation, filtration, a hydrophobic adsorbent, or a combination thereof before the thiourea-containing water is concentrated by the evaporative concentration apparatus. Impurities other than thiourea contained in are removed. Therefore, according to the method for treating thiourea-containing water according to claim 5, the thiourea-containing water is contained in the thiourea-containing water by precipitation, filtration, or a hydrophobic adsorbent before the thiourea-containing water is concentrated by the evaporative concentration apparatus. Compared with the case where impurities other than urea are not removed, the content of impurities other than thiourea contained in the recovered thiourea can be reduced.

  In the thiourea-containing water treatment apparatus according to claim 6, the thiourea concentration unit that concentrates the thiourea-containing water with a reverse osmosis membrane that does not allow thiourea to permeate, and the thiourea-containing solution that has been concentrated by the thiourea concentration unit There is provided a desalting unit that removes ionic substances other than thiourea contained in the thiourea-containing water by desalting the water.

  Therefore, according to the apparatus for treating thiourea-containing water according to the sixth aspect, thiourea, which is a valuable material, can be recovered from the thiourea-containing water. Further, the amount of waste can be reduced as compared with the case where the thiourea-containing water is disposed of without the thiourea being recovered. Specifically, according to the treatment apparatus for thiourea-containing water according to claim 6, the thiourea-containing water is more dehydrated than when the thiourea-containing water is desalted before being concentrated by the reverse osmosis membrane through which thiourea does not permeate. The capacity of the desalting unit for urea-containing water can be reduced. Furthermore, according to the treatment apparatus for thiourea-containing water according to claim 6, when the thiourea-containing water is desalted before being concentrated by the reverse osmosis membrane through which thiourea does not permeate, The risk of impurities being contained in the recovered thiourea can be reduced as the capacity of the desalting section is insufficient. That is, according to the method for treating thiourea-containing water according to claim 6, the thiourea, which is a valuable material, is purified from the thiourea-containing water with high purity while reducing the capacity of the desalinization part of the thiourea-containing water. It can be recovered.

  In the thiourea-containing water treatment apparatus according to claim 7, the thiourea-containing water is concentrated by evaporating and concentrating the thiourea-containing water, and the thiourea-containing water after being concentrated by the evaporating and concentrating apparatus is desalted. And a desalting unit for removing ionic substances other than thiourea contained in the contained water.

  Therefore, according to the apparatus for treating thiourea-containing water according to claim 7, valuable thiourea can be recovered from the thiourea-containing water. Further, the amount of waste can be reduced as compared with the case where the thiourea-containing water is disposed of without the thiourea being recovered. Specifically, according to the treatment apparatus for thiourea-containing water according to claim 7, the thiourea-containing water is removed more than when the thiourea-containing water is desalted before being concentrated by the evaporative concentration apparatus. The capacity of the salt treatment unit can be reduced. Furthermore, according to the processing apparatus for thiourea-containing water according to claim 7, when the thiourea-containing water is desalted before being concentrated by the evaporative concentration apparatus, the thiourea-containing water desalting unit The risk of impurities being contained in the recovered thiourea can be reduced as the capacity of is insufficient. That is, according to the method for treating thiourea-containing water according to claim 7, the thiourea, which is a valuable material, is purified from the thiourea-containing water with high purity while reducing the capacity of the desalination treatment part of the thiourea-containing water. It can be recovered.

  According to the present invention, valuable thiourea can be recovered from thiourea-containing water.

  Specifically, according to the present invention, valuable thiourea can be recovered from thiourea-containing water with high purity while reducing the capacity of the desalination treatment facility for thiourea-containing water.

It is a schematic block diagram of the processing apparatus of the thiourea containing water of 1st Embodiment and Example 1. FIG. It is a schematic block diagram of the processing apparatus of thiourea containing water of 2nd Embodiment and Example 2. FIG. It is a schematic block diagram of the processing apparatus of the thiourea containing water of a comparative example.

  FIG. 1 is a schematic configuration diagram of a thiourea-containing water treatment apparatus according to the first embodiment. In the thiourea-containing water treatment apparatus of the first embodiment, as shown in FIG. 1, when thiourea-containing water containing thiourea is supplied, first, the thiourea-containing water is used as an evaporation concentrator. And then desalted by an ion exchange resin such as 2B3T type or MIXBED type as the desalting apparatus 2. As a result, ionic substances other than thiourea contained in the thiourea-containing water are removed, and high-purity thiourea is recovered.

  In the modified example of the treatment apparatus for thiourea-containing water according to the first embodiment, as the desalting apparatus 2, instead of the ion exchange resin or in addition to the ion exchange resin, the electrodesalination apparatus and thiourea are permeated ( It is also possible to provide a permeation membrane (organic low-exclusion type reverse osmosis membrane), a combination thereof, or the like.

  Further, in another modification of the treatment apparatus for thiourea-containing water according to the first embodiment, before the thiourea-containing water is concentrated by the evaporator 1, precipitation treatment, filtration treatment, for example, a hydrophobic adsorbent such as activated carbon. It is also possible to remove impurities other than thiourea contained in thiourea-containing water by a combination thereof.

  FIG. 2 is a schematic configuration diagram of the treatment apparatus for thiourea-containing water according to the second embodiment. In the thiourea-containing water treatment apparatus according to the second embodiment, as shown in FIG. 2, when thiourea-containing water containing thiourea is supplied, first, a reverse osmosis membrane (organic matter) that does not allow thiourea to permeate. The thiourea-containing water is concentrated by the high exclusion type reverse osmosis membrane) 3 and then desalted by an ion exchange resin such as 2B3T type or MIXBED type as the desalting apparatus 2. As a result, ionic substances other than thiourea contained in the thiourea-containing water are removed, and high-purity thiourea is recovered.

  In the modification of the treatment apparatus for thiourea-containing water according to the second embodiment, as the desalting apparatus 2, an electric desalting apparatus, thiourea permeates instead of or in addition to the ion exchange resin ( It is also possible to provide a permeation membrane (organic low-exclusion type reverse osmosis membrane), a combination thereof, or the like.

  Further, in another modification of the treatment apparatus for thiourea-containing water of the second embodiment, before the thiourea-containing water is concentrated by the reverse osmosis membrane (organic high-exclusion type reverse osmosis membrane) 3 through which thiourea does not permeate. In addition, impurities other than thiourea contained in the thiourea-containing water can be removed by precipitation treatment, filtration treatment, for example, a hydrophobic adsorbent such as activated carbon, or a combination thereof.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to this Example.

[Example 1]
Table 1 shows the composition of thiourea-containing water (titanium oxide photocatalyst production waste water) used in Example 1. The thiourea-containing water (titanium oxide photocatalyst production wastewater) used in Example 1 is a simulation of the neutralized filtrate and its washing water in paragraph [0044] of Patent Document 1, 10-fold diluted solution.

  1 L of simulated waste water (thiourea-containing water) shown in Table 1 is placed in an eggplant flask, and about 5 times (about approximately) using a rotary evaporator 1 (see FIG. 1) N-1100V-W type (manufactured by Tokyo Rika Kikai Co., Ltd.). 200 mL).

  Table 2 shows the composition of thiourea-containing water (titanium oxide photocatalyst production wastewater) supplied to the rotary evaporator 1 (see FIG. 1).

  After that, the thiourea concentrate concentrated by the rotary evaporator 1 (see FIG. 1) is mixed with 1L of cation exchange resin (DOWEX650C manufactured by DOW) and 1L of anion exchange resin (DOWEX550A manufactured by DOW) on two acrylic columns. Water was passed in series at 5 L / h to each of the desalting apparatuses 2 (see FIG. 1) filled to obtain about 200 mL of permeated water.

  Table 3 shows the composition of the thiourea concentrate supplied to the desalting apparatus 2 (see FIG. 1) and the cation load in the desalting apparatus 2 (see FIG. 1).

  Table 4 shows the composition of the permeated water (thiourea concentrate) of the desalting apparatus 2 (see FIG. 1).

  In Example 1, the cation load in the desalting apparatus 2 (see FIG. 1) was low, and the cation exchange resin tower of the desalting apparatus 2 (see FIG. 1) did not break through. Moreover, the value of ammonia as an impurity contained in the finally recovered thiourea concentrate was a low value (0.04 mg / L).

[Example 2]
In Example 2, the thiourea-containing water (titanium oxide photocatalyst production waste water) shown in Table 1 was used as in Example 1.

  1 L of simulated waste water (thiourea-containing water) shown in Table 1 is converted into a flat membrane type organic high exclusion type reverse osmosis membrane (reverse osmosis membrane through which thiourea does not permeate) 3 mm (see FIG. 2) (TC-10 manufactured by Nitto Denko). ) Was concentrated to about 5 times (about 200 mL) at a recovery rate of 80%.

  Table 5 shows the composition of thiourea-containing water (titanium oxide photocatalyst production wastewater) supplied to an organic matter high exclusion type reverse osmosis membrane (reverse osmosis membrane through which thiourea does not permeate) 3 (see FIG. 2).

  Then, the thiourea concentrate concentrated by the organic matter high exclusion type reverse osmosis membrane (reverse osmosis membrane through which thiourea does not permeate) 3 (see FIG. 2) is applied to two acrylic columns with a cation exchange resin (DOWEX650C manufactured by DOW). 1 L and an anion exchange resin (DOWEX DOWEX550A manufactured by DOW) 1 L were respectively passed through the desalting apparatus 2 (see FIG. 2) in series at 5 L / h to obtain about 200 mL of permeated water.

  Table 6 shows the composition of the thiourea concentrate supplied to the desalting apparatus 2 (see FIG. 2) and the cation load in the desalting apparatus 2 (see FIG. 2).

  Table 7 shows the composition of the permeated water (thiourea concentrate) of the desalting apparatus 2 (see FIG. 2).

  In Example 2, the cation load in the desalting apparatus 2 (see FIG. 2) was low, and the cation exchange resin tower of the desalting apparatus 2 (see FIG. 2) did not break through. Moreover, the value of ammonia as an impurity contained in the finally collected thiourea concentrate was a low value (0.5 mg / L).

[Comparative Example]
In the comparative example, the thiourea-containing water (titanium oxide photocatalyst production waste water) shown in Table 1 was used as in Example 1.

  Desalination in which 1 L of simulated waste water (thiourea-containing water) shown in Table 1 is filled in two acrylic columns with 1 L of cation exchange resin (DOWEX 650C manufactured by DOW) and 1 L of anion exchange resin (DOWEX 550A manufactured by DOW) Water was passed in series at 5 L / h with respect to the apparatus 2 (see FIG. 3) to obtain about 1 L of permeated water.

  Table 8 shows the composition of thiourea-containing water (titanium oxide photocatalyst production wastewater) supplied to the desalting apparatus 2 (see FIG. 3) and the cation load in the desalting apparatus 2 (see FIG. 3).

  Thereafter, about 1 L of permeated water (thiourea-containing water) from the desalting apparatus 2 (see FIG. 3) was placed in a round bottom flask, and rotary evaporator 1 (see FIG. 3) N-1100V-W type (manufactured by Tokyo Rika Instruments Co., Ltd.) Was concentrated to about 5 times (about 200 mL).

  Table 9 shows the composition of the permeated water (thiourea-containing water) of the desalting apparatus 2 (see FIG. 3) supplied to the rotary evaporator 1 (see FIG. 3).

  Table 10 shows the composition of the thiourea concentrate concentrated by the rotary evaporator 1 (see FIG. 3).

  In the comparative example, since the cation load in the desalting apparatus 2 (see FIG. 3) was high, the cation exchange resin tower of the desalting apparatus 2 (see FIG. 3) broke through and was finally recovered. In the thiourea concentrate, 35 mg / L of ammonia as an impurity remained.

  That is, according to Examples 1 and 2, the capacity (specifically, the cation exchange resin tower (resin capacity)) of the desalting apparatus 2 (see FIGS. 1, 2 and 3) is smaller than that of the comparative example. It was found that impurities contained in the thiourea concentrate can be reduced.

DESCRIPTION OF SYMBOLS 1 Evaporator 2 Desalination equipment 3 Organic matter high exclusion type reverse osmosis membrane (reverse osmosis membrane which thiourea does not permeate)

Claims (7)

Concentrate water containing thiourea with a reverse osmosis membrane that does not allow thiourea to pass through
By desalting the thiourea-containing water after being concentrated by the reverse osmosis membrane that does not allow thiourea to permeate, ionic substances other than thiourea contained in the thiourea-containing water are removed, and the thiourea-containing water is converted to thiourea-containing water. A method for treating thiourea-containing water, wherein the thiourea contained is recovered. Concentrate water containing thiourea with an evaporative concentrator,
By desalting the thiourea-containing water after being concentrated by the evaporation concentrator, ionic substances other than thiourea contained in the thiourea-containing water are removed, and the thiourea contained in the thiourea-containing water is removed. A method for treating thiourea-containing water, comprising collecting the thiourea-containing water.   2. An ionic substance other than thiourea contained in thiourea-containing water is removed by an ion exchange resin, an electric desalting apparatus, a reverse osmosis membrane through which thiourea permeates, or a combination thereof. Or the processing method of the thiourea containing water of 2.   Remove impurities other than thiourea in the thiourea-containing water by precipitation, filtration, hydrophobic adsorbent, or a combination before the thiourea-containing water is concentrated by a reverse osmosis membrane that does not allow thiourea to permeate The method for treating thiourea-containing water according to claim 1 or 3, wherein:   It is characterized by removing impurities other than thiourea contained in the thiourea-containing water by precipitation, filtration, hydrophobic adsorbent, or a combination thereof before the thiourea-containing water is concentrated by the evaporative concentration apparatus. The method for treating thiourea-containing water according to claim 2 or 3. A thiourea concentration section that concentrates thiourea-containing water by a reverse osmosis membrane that does not allow thiourea to permeate;
And a desalting unit that removes ionic substances other than thiourea contained in the thiourea-containing water by subjecting the thiourea-containing water after being concentrated by the thiourea concentration unit to a desalting treatment. An apparatus for treating thiourea-containing water. An evaporative concentration apparatus for concentrating thiourea-containing water;
And a desalting treatment unit that removes ionic substances other than thiourea contained in the thiourea-containing water by desalting the thiourea-containing water after being concentrated by the evaporative concentration apparatus. An apparatus for treating thiourea-containing water.

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