JP3325288B2 - Aluminum electroplating wastewater treatment method - Google Patents
Aluminum electroplating wastewater treatment methodInfo
- Publication number
- JP3325288B2 JP3325288B2 JP10724792A JP10724792A JP3325288B2 JP 3325288 B2 JP3325288 B2 JP 3325288B2 JP 10724792 A JP10724792 A JP 10724792A JP 10724792 A JP10724792 A JP 10724792A JP 3325288 B2 JP3325288 B2 JP 3325288B2
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- ppm
- ferric
- treatment
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Classifications
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W10/00—Technologies for wastewater treatment
- Y02W10/10—Biological treatment of water, waste water, or sewage
Landscapes
- Activated Sludge Processes (AREA)
- Removal Of Specific Substances (AREA)
- Treatment Of Water By Oxidation Or Reduction (AREA)
- Water Treatment By Sorption (AREA)
Description
【０００１】[0001]
【産業上の利用分野】本発明は、難生分解性のオニウム
ハロゲン化物を含むアルミニウム電気めっきの排水処理
法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for treating aluminum electroplating wastewater containing a hardly biodegradable onium halide.
【０００２】[0002]
【従来の技術】アルミニウムめっき法としては、従来、
溶融めっき法が主に用いられているが、この方法では、
アルミニウムを６００℃以上の高温に加熱、溶融する必
要があるため熱源の消費が大きく、まためっき槽の部材
及び耐熱性ライニングが要求されるので、最近では、溶
融塩浴や、２００℃以下の比較的低い温度のめっき液を
使用した電気めっき方法等が開発されている（特開昭６
３−２６３９９号公報、特開昭６４−８７７９９号公
報、特開平１−２７２７８８号公報、特開平１−２７２
７９０号公報等）。2. Description of the Related Art Conventionally, as an aluminum plating method,
Hot-dip plating is mainly used, but in this method,
Since it is necessary to heat and melt aluminum to a high temperature of 600 ° C. or higher, the consumption of heat source is large, and since the members of the plating tank and heat-resistant lining are required, recently, a molten salt bath or a 200 ° C. or lower An electroplating method using a plating solution at a very low temperature has been developed (Japanese Patent Laid-Open No.
JP-A-3-26399, JP-A-64-87799, JP-A-1-272788, JP-A-1-272
790, etc.).
【０００３】めっき浴としては、一般的にアルキルピリ
ジニウムハロゲン化物、ジアルキルイミダゾリウムハロ
ゲン化物等のオニウムハロゲン化物及びハロゲン化アル
ミニウムからなる非水系の溶液が用いられているが、こ
のめっき浴成分は、空気中の酸素や水分と反応して固形
物を析出するため、めっき物に付着しためっき浴成分は
水洗する必要がある。したがって、この洗浄排水には、
オニウムハロゲン化物を大量に含有するのでＣＯＤ値が
高く排水処理を要するが、オニウムハロゲン化物は難生
分解性であるため、排水処理が困難であった。As a plating bath, a non-aqueous solution comprising an onium halide such as an alkylpyridinium halide and a dialkylimidazolium halide and an aluminum halide is generally used. Since it reacts with oxygen and moisture in the solution to precipitate solids, it is necessary to wash the plating bath components adhered to the plating with water. Therefore, this washing wastewater includes
Since a large amount of onium halide is contained, the COD value is high and wastewater treatment is required. However, wastewater treatment is difficult because onium halide is hardly biodegradable.
【０００４】また、特開平１−１０４８００号公報、特
開平１−２１９１９９号公報には、めっき物を有機溶媒
で洗浄した後、有機溶媒中のアルキルピリジニウムハロ
ゲン化物を固体で回収する方法が示されている。しかし
ながら、この方法では可燃性物質を大量に用いるので安
全性に問題点があると共に、有機溶媒を除去するのに多
くのエネルギーを要するのでコストが高くなるという問
題点があった。Further, JP-A-1-104800 and JP-A-1-219199 disclose a method of washing a plated product with an organic solvent and then recovering an alkylpyridinium halide in the organic solvent as a solid. ing. However, this method has a problem in safety because a large amount of a combustible substance is used, and also has a problem in that a large amount of energy is required to remove the organic solvent, so that the cost is high.
【０００５】[0005]
【発明が解決しようとする課題】本発明の目的は、オニ
ウムハロゲン化物を含有するアルミニウム電気めっき排
水を、安全にかつ安価に処理できる方法を提供すること
にある。SUMMARY OF THE INVENTION An object of the present invention is to provide a method for safely and inexpensively treating aluminum electroplating wastewater containing onium halide.
【０００６】[0006]
【課題を解決するための手段】本発明は、オニウムハロ
ゲン化物を含有するアルミニウム電気めっき排水を、鉄
の存在下に過酸化水素で酸化処理した後、活性汚泥処理
することを特徴とする排水処理法である。According to the present invention, there is provided a wastewater treatment comprising the steps of oxidizing aluminum electroplating wastewater containing onium halide with hydrogen peroxide in the presence of iron, followed by activated sludge treatment. Is the law.
【０００７】以下、本発明を詳細に説明する。本発明の
方法で処理する排水は、めっき液の希釈水溶液と同じ組
成であり、ハロゲン化アルミニウム及びオニウムハロゲ
ン化物を含有する水溶液である。オニウムハロゲン化物
としては、テトラエチルアンモニウムブロマイド、トリ
メチルエチルアンモニウムクロライド等の四級アンモニ
ウム塩、ブチルピリジニウムクロライド等のピリジニウ
ム塩、１−エチル−３−メチルイミダゾリウムクロライ
ド等のイミダゾリウム塩、エチルトリブチルホスホニウ
ムブロマイド等のホスホニウム塩などを挙げることがで
きる。Hereinafter, the present invention will be described in detail. The waste water treated by the method of the present invention has the same composition as the diluted aqueous solution of the plating solution, and is an aqueous solution containing aluminum halide and onium halide. Examples of onium halides include quaternary ammonium salts such as tetraethylammonium bromide and trimethylethylammonium chloride, pyridinium salts such as butylpyridinium chloride, imidazolium salts such as 1-ethyl-3-methylimidazolium chloride, and ethyltributylphosphonium bromide. And the like.
【０００８】本発明は、鉄の存在下に過酸化水素で上記
排水を酸化処理する。本発明に用いる鉄としては、硫酸
第一鉄、硫酸第二鉄、塩化第一鉄、塩化第二鉄、硝酸第
二鉄、シュウ酸第一鉄、リン酸第二鉄等を挙げることが
できる。According to the present invention, the wastewater is oxidized with hydrogen peroxide in the presence of iron. Examples of iron used in the present invention include ferrous sulfate, ferric sulfate, ferrous chloride, ferric chloride, ferric nitrate, ferrous oxalate, and ferric phosphate. .
【０００９】鉄の添加量は、処理する排水のＣＯＤ（Ｃ
ｒ）値(ppm) に対し、Ｆｅ換算で０．５〜１．５ppm が
好ましい。過酸化水素の添加量は、処理する排水のＣＯ
Ｄ（Ｃｒ）値(ppm) に対し、Ｏ換算で０．５〜１．５pp
m が好ましい。鉄及び過酸化水素の添加量が０．５ppm
未満のときには、処理効率が低く、酸化反応が十分に進
行しない場合があり、１．５ppm を超えても処理効率は
あまり向上しない。The amount of iron added depends on the COD (C
r) It is preferably 0.5 to 1.5 ppm in terms of Fe with respect to the value (ppm). The amount of hydrogen peroxide added depends on the amount of CO
0.5 to 1.5pp in O conversion with respect to D (Cr) value (ppm)
m is preferred. 0.5ppm of iron and hydrogen peroxide
If it is less than 1.5 ppm, the treatment efficiency is low and the oxidation reaction may not proceed sufficiently. If it exceeds 1.5 ppm, the treatment efficiency does not improve much.
【００１０】酸化処理は、硫酸等の酸を用い、ｐＨ２〜
４に調整して行うのが好ましい。ｐＨが４を超えると鉄
が水酸化物として析出し、酸化反応が十分に進行しない
場合があるので好ましくない。酸化処理の温度は、１〜
９９℃が好ましく、一般的には室温で２時間以上処理す
ることにより反応は十分に進行するが、排熱を利用し反
応温度を上昇させ、反応時間を短縮することもできる。
また、酸化処理は効率を高めるために撹拌するのが好ま
しい。The oxidation treatment uses an acid such as sulfuric acid and has a pH of 2
It is preferable to adjust to 4. If the pH exceeds 4, iron is precipitated as a hydroxide, and the oxidation reaction may not proceed sufficiently. The temperature of the oxidation treatment is 1 to
The reaction is preferably carried out at room temperature for 2 hours or more, but the reaction proceeds sufficiently. However, the reaction time can be shortened by increasing the reaction temperature by using exhaust heat.
In addition, it is preferable to stir the oxidation treatment in order to increase the efficiency.
【００１１】次に、酸化処理排水を水酸化ナトリウム等
のアルカリを用いてｐＨ７〜８に調整することにより、
排水中の鉄及びアルミニウムを水酸化物として析出さ
せ、さらに凝集剤を添加して数時間静置し水酸化物を沈
降させて分離除去する。凝集剤としては、ポリアクリル
酸ナトリウム等の高分子凝集剤、ドデシルベンゼンスル
ホン酸ナトリウム等の界面活性剤、活性シリカ等の酸化
物などを用いることができる。Next, the pH of the oxidized waste water is adjusted to 7 to 8 using an alkali such as sodium hydroxide.
Iron and aluminum in the wastewater are precipitated as hydroxide, and a coagulant is further added, and the mixture is allowed to stand for several hours to settle and separate the hydroxide. As the coagulant, a polymer coagulant such as sodium polyacrylate, a surfactant such as sodium dodecylbenzenesulfonate, an oxide such as activated silica, and the like can be used.
【００１２】本発明の処理法は、このようにして金属成
分を除去した酸化処理排水を活性汚泥処理する。活性汚
泥法としては、特に制限はなく、例えば、馴致汚泥を用
いた回分式、連続式等の公知の方法を用いることができ
る。処理条件としては、温度は２０〜３０℃、ＭＬＳＳ
は１，０００〜３，０００mg/l、ＢＯＤ負荷は０．５〜
０．６kg/m3 ・日が好ましい。ばっ気形式としては、吹
込式又は機械式のいずれも適用することができるが、処
理効率を考慮すると吹込式が好ましい。In the treatment method of the present invention, the oxidized wastewater from which the metal components have been removed in this way is subjected to activated sludge treatment. The activated sludge method is not particularly limited, and for example, a known method such as a batch type using continuous sludge or a continuous type can be used. As the processing conditions, the temperature is 20 to 30 ° C., and the MLSS
1,000-3,000 mg / l, BOD load 0.5-
0.6 kg / m 3 · day is preferred. As the aeration type, either a blow-in type or a mechanical type can be applied, but a blow-in type is preferable in consideration of processing efficiency.
【００１３】本発明の処理法は、このように活性汚泥処
理した排水を、さらに活性炭処理するのが好ましい。活
性炭としては、市販の粒状又は粉末のいずれも用いるこ
とができるが、取り扱いの容易性を考慮すると粒状炭が
好ましい。処理形式は、回分式又は流通式のいずれの形
式も適用することができる。処理条件としては、例えば
流通式の場合、操作温度は１０〜４０℃、ＳＶは１〜１
０リットル／時間が好ましい。In the treatment method of the present invention, it is preferable that the wastewater thus treated with activated sludge is further treated with activated carbon. As the activated carbon, any of commercially available granules and powders can be used, but granular charcoal is preferable in consideration of easy handling. As the processing format, any of a batch type and a distribution type can be applied. As the processing conditions, for example, in the case of a flow type, the operating temperature is 10 to 40 ° C., and the SV is 1 to 1
0 liters / hour is preferred.
【００１４】[0014]
実施例１ １−エチル−３−メチルイミダゾリウムクロライド３３
モル％及び三塩化アルミニウム６７モル％を含有するめ
っき液を水で希釈し、１−エチル−３−メチルイミダゾ
リウムクロライドと三塩化アルミニウムを合計で、１，
２５０ppm 含有する水溶液３，０００mlを調製し、硫酸
でｐＨ３にした。得られた水溶液のＢＯＤは１ppm 以
下、ＣＯＤ（Ｍｎ）は９８ppm 、ＣＯＤ（Ｃｒ）は６９
９ppm であった。Example 1 1-ethyl-3-methylimidazolium chloride 33
The plating solution containing 5 mol% and 67 mol% of aluminum trichloride was diluted with water, and 1-ethyl-3-methylimidazolium chloride and aluminum trichloride were added in a total amount of 1,
3,000 ml of an aqueous solution containing 250 ppm was prepared and adjusted to pH 3 with sulfuric acid. The BOD of the obtained aqueous solution is 1 ppm or less, COD (Mn) is 98 ppm, and COD (Cr) is 69 ppm.
It was 9 ppm.
【００１５】得られた水溶液に、硫酸第一鉄１０．４g
及び３０％過酸化水素水１２．７gを添加し、室温で１
５０rpm で３時間撹拌した。次に水酸化ナトリウムでｐ
Ｈを７．５に調整して１０分間撹拌し、凝集剤１５mgを
添加して１５分間静置した後、処理液（以下、処理液Ａ
という）をろ別、回収した。処理液ＡのＢＯＤは１２１
ppm 、ＣＯＤ（Ｍｎ）は１１２ppm 、ＣＯＤ（Ｃｒ）は
３７２ppm であった。また、処理液ＡをＧＣ−ＭＳ分析
したところ、生分解が可能な１−メチルイミダゾール、
Ｎ−メチルアセトアミド等を検出した。To the obtained aqueous solution, 10.4 g of ferrous sulfate was added.
And 12.7 g of a 30% aqueous hydrogen peroxide solution.
Stir at 50 rpm for 3 hours. Then p with sodium hydroxide
H was adjusted to 7.5, the mixture was stirred for 10 minutes, 15 mg of a coagulant was added, and the mixture was allowed to stand for 15 minutes.
Was collected by filtration. The BOD of the processing solution A is 121
ppm, COD (Mn) was 112 ppm, and COD (Cr) was 372 ppm. In addition, GC-MS analysis of the treatment solution A showed that biodegradable 1-methylimidazole,
N-methylacetamide and the like were detected.
【００１６】次に、処理液Ａ１，４００mlと馴致汚泥
０．６mg/lの混合液（ＭＬＳＳ１，９４０mg/l) を調製
し、室温でエアーポンプによりばっ気し、回分式活性汚
泥処理を行った。ＢＯＤ、ＣＯＤ（Ｍｎ）の経時変化を
表１に示す。４８時間の活性汚泥処理によって、処理液
ＡのＢＯＤを９０％以上低減することができた。Next, a mixed solution (MLSS: 1,940 mg / l) of 1,400 ml of the treatment liquid A and 0.6 mg / l of the sludge was prepared, aerated with an air pump at room temperature, and subjected to batch activated sludge treatment. . Table 1 shows changes over time in BOD and COD (Mn). By the activated sludge treatment for 48 hours, the BOD of the treatment liquid A could be reduced by 90% or more.
【００１７】[0017]
【表１】 [Table 1]
【００１８】４８時間の活性汚泥処理によって得られた
処理液（以下、処理液Ｂという）を活性炭で吸着処理し
た。吸着処理は、直径１８mm、高さ１ｍの吸着塔に石炭
系活性炭を２１６ml（充填密度０．５g/ml) 充填し、室
温で下向流によりＳＶ＝４．５で通水することにより行
った。得られた処理液ＣのＢＯＤは１．５ppm 、ＣＯＤ
（Ｍｎ）は３．６ppm であった。全行程を通じてのＢＯ
Ｄ、ＣＯＤ（Ｍｎ）の変化を表２に示す。The treatment liquid obtained by the activated sludge treatment for 48 hours (hereinafter referred to as treatment liquid B) was subjected to adsorption treatment with activated carbon. The adsorption treatment was carried out by filling an adsorption tower having a diameter of 18 mm and a height of 1 m with coal-based activated carbon in an amount of 216 ml (packing density: 0.5 g / ml) and passing water at a room temperature downward at SV = 4.5. . The BOD of the obtained processing solution C is 1.5 ppm, COD
(Mn) was 3.6 ppm. BO throughout the entire journey
Table 2 shows changes in D and COD (Mn).
【００１９】[0019]
【表２】 [Table 2]
【００２０】実施例２ 実施例１のめっき液に代えて、Ｎ−ブチルピリジニウム
クロライド（３３モル％）及び三塩化アルミニウム（６
７モル％）を含有するめっき液を用いた他は、実施例１
と同様にして処理を行った。その結果、ＢＯＤ、ＣＯＤ
とも十分に低減した。全行程を通じてのＢＯＤ、ＣＯＤ
（Ｍｎ）の変化を表３に示す。Example 2 In place of the plating solution of Example 1, N-butylpyridinium chloride (33 mol%) and aluminum trichloride (6
Example 1 except that a plating solution containing (7 mol%) was used.
The processing was performed in the same manner as described above. As a result, BOD, COD
Both were sufficiently reduced. BOD, COD throughout the process
Table 3 shows the change in (Mn).
【００２１】[0021]
【表３】 [Table 3]
【００２２】比較例１ 実施例１で使用した水溶液（ＣＯＤ＝９８ppm 、ＢＯＤ
＜１ppm ）を、酸化処理せずに、実施例１の条件で回分
式活性汚泥処理した。その結果、３００時間経過後もＣ
ＯＤは９８ppm であった。Comparative Example 1 The aqueous solution used in Example 1 (COD = 98 ppm, BOD
<1 ppm) was subjected to batch activated sludge treatment under the conditions of Example 1 without oxidation treatment. As a result, even after 300 hours, C
The OD was 98 ppm.
【００２３】[0023]
【発明の効果】本発明によると、酸化処理により金属成
分を除去することができると共に難生分解性成分である
オニウムハロゲン化物を、生分解が可能な物質に変化さ
せることができるので、活性汚泥処理することができ、
アルミニウム電気めっき排水を安全にかつ安価に処理す
ることができる。According to the present invention, activated sludge can be obtained because the metal component can be removed by oxidation treatment and the onium halide, which is a hardly biodegradable component, can be changed to a biodegradable substance. Can be processed,
The aluminum electroplating wastewater can be safely and inexpensively treated.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 鷲見 宗一 三重県四日市市川尻町1000番地 三菱油 化エンジニアリング株式会社 四日市支 社内 (72)発明者 岩崎 博司 三重県四日市市川尻町1000番地 三菱油 化エンジニアリング株式会社 四日市支 社内 (56)参考文献 特開 平３−262594（ＪＰ，Ａ) 特開 昭61−197093（ＪＰ，Ａ) 特開 昭55−27098（ＪＰ，Ａ) 特開 昭52−142866（ＪＰ，Ａ) (58)調査した分野(Int.Cl.7，ＤＢ名) C02F 3/12 C02F 9/00 501 - 502 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Soichi Sumi, 1000 Kawajiri-cho, Yokkaichi, Mie Pref.Mitsubishi Yuka Engineering Co., Ltd. Engineering Co., Ltd. Yokkaichi branch (56) References JP-A-3-262594 (JP, A) JP-A-61-197093 (JP, A) JP-A-55-27098 (JP, A) JP-A-52-142866 (JP, A) (58) Field surveyed (Int. Cl. 7 , DB name) C02F 3/12 C02F 9/00 501-502
Claims (3)
ロゲン化物を含有するアルミニウム電気めっき排水を処
理する方法であって、該排水を、 （１）硫酸第一鉄、硫酸第二鉄、塩化第一鉄、塩化第二
鉄、硝酸第二鉄、シュウ酸第二鉄、及びリン酸第二鉄か
らなる群より選ばれる１種以上の鉄化合物の存在下に、
過酸化水素で酸化処理する工程；次いで （２）活性汚泥処理する工程を含むことを特徴とする排
水処理法。1. A method for treating aluminum electroplating wastewater containing aluminum halide and onium halide, comprising: (1) ferrous sulfate, ferric sulfate, ferrous chloride, chloride, Ferric, ferric nitrate, ferric oxalate, and in the presence of one or more iron compounds selected from the group consisting of ferric phosphate,
A wastewater treatment method comprising a step of oxidizing with hydrogen peroxide; and (2) a step of treating with activated sludge.
下で、該鉄化合物を、該排水のＣＯＤ（Ｃｒ）値（pp
m）に対し、Ｆｅ換算で０．５〜１．５ppm用い、そして
該過酸化水素を、該排水のＣＯＤ（Ｃｒ）値（ppm）に
対し、Ｏ換算で０．５〜１．５ppm用いて酸化処理す
る、請求項１記載の方法。2. The method according to claim 1, wherein the step (1) is carried out under the condition of pH 2 to 4 by changing the iron compound to a COD (Cr) value (pp
m), 0.5 to 1.5 ppm in terms of Fe, and the hydrogen peroxide is used in an amount of 0.5 to 1.5 ppm in terms of O with respect to the COD (Cr) value (ppm) of the wastewater. The method according to claim 1, wherein the oxidation treatment is performed.
処理する工程を含む、請求項１又は２記載の方法。3. The method according to claim 1, further comprising, after the step (2), a step of (3) treating with activated carbon.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10724792A JP3325288B2 (en) | 1992-04-27 | 1992-04-27 | Aluminum electroplating wastewater treatment method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10724792A JP3325288B2 (en) | 1992-04-27 | 1992-04-27 | Aluminum electroplating wastewater treatment method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH05301098A JPH05301098A (en) | 1993-11-16 |
| JP3325288B2 true JP3325288B2 (en) | 2002-09-17 |
Family
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP10724792A Expired - Fee Related JP3325288B2 (en) | 1992-04-27 | 1992-04-27 | Aluminum electroplating wastewater treatment method |
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| Country | Link |
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| JP (1) | JP3325288B2 (en) |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| JP2016044147A (en) * | 2014-08-25 | 2016-04-04 | 住友電気工業株式会社 | Manufacturing method of organic halide |
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| JP2016044339A (en) * | 2014-08-25 | 2016-04-04 | 住友電気工業株式会社 | Method for producing organic halide |
| CN104495997A (en) * | 2015-01-09 | 2015-04-08 | 刘树芹 | Printing and dyeing wastewater cleaning agent, as well as preparation method and application thereof |
| CN116282717B (en) * | 2023-03-24 | 2024-03-12 | 湖北朗润环保科技有限公司 | Comprehensive treatment method for production wastewater |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| JP2016044147A (en) * | 2014-08-25 | 2016-04-04 | 住友電気工業株式会社 | Manufacturing method of organic halide |
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| Publication number | Publication date |
|---|---|
| JPH05301098A (en) | 1993-11-16 |
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