JPH0616421A - Treatment of liquid industrial wastes - Google Patents
Treatment of liquid industrial wastesInfo
- Publication number
- JPH0616421A JPH0616421A JP10087791A JP10087791A JPH0616421A JP H0616421 A JPH0616421 A JP H0616421A JP 10087791 A JP10087791 A JP 10087791A JP 10087791 A JP10087791 A JP 10087791A JP H0616421 A JPH0616421 A JP H0616421A
- Authority
- JP
- Japan
- Prior art keywords
- copper
- waste liquid
- sulfide
- sodium sulfide
- treatment
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Landscapes
- Removal Of Specific Substances (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、産業廃液の処理方法に
関し、更に言えば、化学品製造業等から廃出される硫化
ソーダ廃液と銅のプリント配線基板のエッチング廃液と
を混合して両液の無害化を同時に行うことを意図するも
のである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for treating industrial waste liquid, and more specifically, it mixes a sodium sulfide waste liquid discharged from a chemical product manufacturing industry and a copper printed wiring board etching waste liquid. It is intended to detoxify at the same time.
【０００２】[0002]
【従来の技術】硫化ソーダ溶液は化学業界をはじめ、各
種の産業分野から様々な濃度で廃出する。例えば、代表
的にはバリウム塩製造業から廃出される。すなわち、バ
リウム塩は重晶石の還元焙焼及び浸出によって得られる
硫化バリウム溶液を出発原料とするため、硫酸バリウム
を製造する場合、次式の反応 ＢａＳ＋Ｈ2ＳＯ4→ＢａＳＯ4↓＋Ｈ2Ｓ (１) Ｈ2Ｓ＋２ＮａＯＨ→Ｎａ2Ｓ＋２Ｈ2Ｏ (２) ＢａＳ＋Ｎａ2ＳＯ4→ＢａＳＯ4↓＋Ｎａ2Ｓ (３) により硫化ソーダ溶液が副生する。2. Description of the Related Art Sodium sulfide solution is discharged in various concentrations from various industrial fields including the chemical industry. For example, it is typically discharged from the barium salt manufacturing industry. That is, since the barium salt uses a barium sulfide solution obtained by the reduction roasting and leaching of barite as a starting material, when producing barium sulfate, the reaction BaS + H 2 SO 4 → BaSO 4 ↓ + H 2 S ( 1) H 2 S + 2 NaOH → Na 2 S + 2H 2 O (2) BaS + Na 2 SO 4 → BaSO 4 ↓ + Na 2 S (3), soda sulfide solution is by-produced.
【０００３】もっとも、上記溶液は比較的濃厚であるた
め、晶析及び溶融してフレーク状硫化ソーダとして回収
し、有用な工業原料として利用されるが、低濃度の母液
やバランスよく経済的に回収できない硫化ソーダが廃液
として多量に発生する。However, since the above-mentioned solution is relatively concentrated, it is crystallized and melted to be recovered as flaky sodium sulfide, which is used as a useful industrial raw material. A large amount of sodium sulfide that cannot be produced is generated as waste liquid.
【０００４】更に、石油精製の際にも、硫化ソーダが副
生するし、脱毛に用いた硫化ソーダが鞣皮業界から、あ
るいは製紙業界からも硫化ソーダがそれぞれ廃出され
る。Further, when refining petroleum, sodium sulfide is by-produced, and the sodium sulfide used for dehairing is discharged from the tanning industry or the paper manufacturing industry.
【０００５】係る硫化ソーダ廃液は強アルカリ性である
のみならず、酸で中和すると有害な硫化水素ガスを発生
させるため、低濃度であってもそのまま放出することは
できない。Such a sodium sulfide waste liquid is not only strongly alkaline, but when it is neutralized with an acid, it produces harmful hydrogen sulfide gas. Therefore, even if the concentration is low, it cannot be released as it is.
【０００６】従来、硫化ソーダの無害化は通常、酸化処
理によるが、例えば活性炭などの存在下で空気酸化によ
り硫酸ソーダに転換せしめ、中和後放流することが知ら
れている。[0006] Conventionally, detoxification of sodium sulfide is usually carried out by an oxidation treatment, but it is known that sodium sulfide is converted into sodium sulfate by air oxidation in the presence of activated carbon, etc., and neutralized before being discharged.
【０００７】他の方法として、硫化ソーダ溶液と亜硫酸
ガスまたは亜硫酸水を反応させて硫黄を析出させるクラ
ウス方式の処理方法がある。[0007] As another method, there is a Claus type processing method in which sulfur sulfide solution is reacted with sulfurous acid gas or sulfurous acid water to deposit sulfur.
【０００８】他方、電子工業界では、銅のプリント配線
基板のエッチングを行った処理液(以下、「銅板エッチ
ング廃液」という)が多量に発生する。従来、係る銅板
エッチング廃液は船底塗料用の防汚顔料である亜酸化銅
として回収利用されている(例えば、特開昭55−71629号
公報、特開昭56−155020号公報)。On the other hand, in the electronic industry, a large amount of processing liquid for etching a copper printed wiring board (hereinafter referred to as "copper plate etching waste liquid") is generated. Conventionally, such copper plate etching waste liquid has been collected and utilized as cuprous oxide, which is an antifouling pigment for ship bottom paints (for example, JP-A-55-71629 and JP-A-56-155020).
【０００９】また、他の方法として各種の銅塩類または
銅粉として回収し、有効利用することも知られている。As another method, it is known that various copper salts or copper powders are recovered and used effectively.
【００１０】[0010]
【発明が解決しようとする課題】しかしながら、上記の
ような空気酸化による硫化ソーダ廃液の処理では、酸化
が不充分で度々Ｓ2Ｏ3 2-やＳＯ3 2-が残留するので問題
が多い。また、クラウス方式は大きな設備投資を伴う処
理費が高いのみならず、二次生成物たるコロイド硫黄の
取り扱い及び処理に問題が多い。However, in the treatment of the sodium sulfide waste liquid by the air oxidation as described above, the oxidation is insufficient and S 2 O 3 2− and SO 3 2− often remain, which causes many problems. In addition, the Claus method not only has a high treatment cost with a large capital investment, but also has many problems in handling and treating colloidal sulfur as a secondary product.
【００１１】硫化ソーダは硫化水素を発生し易いので、
完全に無害化しなければならず、これを廃出する業界に
おいて、如何に低コストで処理できるかが、なお今日的
重要な問題となっている。Since sodium sulfide easily produces hydrogen sulfide,
In the industry that must be completely rendered harmless, and how to dispose of it, how low the cost can be treated is still an important issue today.
【００１２】他方、銅板エッチング廃液は上記のような
有効利用がなされてはいるが、なお、不充分で強酸性の
重金属を含む廃液の無害化並びに銅有価成分の合理的回
収もまた業界の重大な問題となっていた。On the other hand, although the copper plate etching waste liquid has been effectively used as described above, detoxification of waste liquid containing insufficient and strongly acidic heavy metals and rational recovery of copper valuable components are also important in the industry. It was a problem.
【００１３】本発明者らは硫化ソーダ廃液の低コストな
処理につき、これまで鋭意検討を重ねてきたが、この廃
液と銅エッチング廃液とを混合すると、両廃液の処理が
一挙にできることを知見し、本発明を完成した。The inventors of the present invention have conducted intensive studies on the low-cost treatment of the sodium sulfide waste liquid, but have found that the waste liquid can be treated at once by mixing the waste liquid with the copper etching waste liquid. The present invention has been completed.
【００１４】すなわち、本発明は硫化ソーダ廃液と銅板
エッチング廃液とを同時に無害化するに止どまらず、積
極的に銅有価成分を回収する方法を提供することにあ
る。That is, the present invention provides a method for positively recovering a valuable copper component, not only to make the sodium sulfide waste liquid and the copper plate etching waste liquid harmless at the same time.
【００１５】[0015]
【課題を解決するための手段】本発明が提供しようとす
る方法は、硫化ソーダ廃液と銅板エッチング廃液とを混
合、反応させて硫化銅として回収処理することを構成上
の特徴とするものである。The method to be provided by the present invention is characterized in that the sodium sulfide waste liquid and the copper plate etching waste liquid are mixed and reacted to recover as copper sulfide. .
【００１６】本発明において、硫化ソーダ廃液とは、そ
の性質上硫化ソーダを含有する溶液であって、水硫化ソ
ーダ、多硫化ソーダを含んでいてもよく、また、バリウ
ム、ストロンチウムまたはカルシウム等のアルカリ土類
金属硫化物を含有するものであってもよい。In the present invention, the sodium sulfide waste liquor is a solution containing sodium sulfide by its nature and may contain sodium hydrosulfide or sodium polysulfide. Also, an alkali such as barium, strontium or calcium is used. It may contain an earth metal sulfide.
【００１７】他方、銅板エッチング廃液というのは、塩
化第２銅溶液あるいは過酸化水素の如き酸化剤を含有す
る塩酸溶液で銅のプリント配線基板のエッチングを行っ
た処理液であって、通常次のものが含まれている： ＣｕＣｌ：０〜５０ｇ／リットル ＣｕＣｌ2：３０〜３００ｇ／リットル 遊離ＨＣｌ：１０〜２００ｇ／リットル その他：０〜３０ｇ／リットル その他の成分として、Ｎｉ2+、Ｚｎ2+、Ｆｅ3+等の重金
属イオン、ＰＯ4 3-、Ｆ-などの陰イオンあるいは有機物
を若干量含むが、その主組成は遊離塩酸を含有する塩化
第２銅水溶液である。On the other hand, the copper plate etching waste liquid is a treatment liquid obtained by etching a copper printed wiring board with a cupric chloride solution or a hydrochloric acid solution containing an oxidizing agent such as hydrogen peroxide, and is usually the following. includes those: CuCl: 0~50g / l CuCl 2: 30~300g / l free HCl: 10 to 200 g / l other: 0~30g / liter other ingredients, Ni 2+, Zn 2+, Heavy metal ions such as Fe 3+ , anions such as PO 4 3− and F − , or organic substances are contained in a slight amount, but the main composition is an aqueous cupric chloride solution containing free hydrochloric acid.
【００１８】本発明において、上記銅板エッチング廃液
をそのまま処理液として用いることができるが、必要に
応じ濾過または空気酸化や過酸化水素などの酸化処理を
施して完全に第２銅塩とさせた後用いてもよい。In the present invention, the above copper plate etching waste liquid can be used as it is as a treatment liquid, but after it is filtered or subjected to air oxidation or oxidation treatment such as hydrogen peroxide, it is completely converted into a cupric salt. You may use.
【００１９】本発明は係る両液を混合し、反応させて硫
化銅に転換せしめ、次いで固液分離して硫化銅を回収す
る。反応方式として、両液を同時に添加する方法、硫化
ソーダ廃液に銅板エッチング廃液を添加する方法または
その逆の添加方法など、いずれの方式でも差し支えない
が、同時添加方法が連続処理が可能なため操作上有利で
ある。In the present invention, the two liquids are mixed, reacted to be converted into copper sulfide, and then solid-liquid separated to recover copper sulfide. As the reaction method, either method may be used, such as a method of adding both solutions at the same time, a method of adding a copper plate etching waste solution to a sodium sulfide waste solution, or the opposite method. This is advantageous.
【００２０】本反応は極めて量論的かつ速やかに進行す
るので、温度や濃度は臨界的である必要はないが、後の
固液分離の操作上濾過性のよい硫化銅が生成するような
条件を設定し、また、反応終了後必要に応じ加熱下で熟
成処理を施すのが好ましい。Since this reaction proceeds extremely quantitatively and rapidly, it is not necessary that the temperature and the concentration are critical, but the conditions under which copper sulfide having good filterability is produced in the subsequent solid-liquid separation operation. Is set, and after the completion of the reaction, it is preferable to perform an aging treatment under heating if necessary.
【００２１】本発明に係る廃液の処理方法は上記理由か
ら両液の一方または双方が濃厚液から低濃度まで幅広く
適用でき、かつ合理的に処理できることにある。特に、
銅板エッチング廃液に対し、硫化ソーダ廃液が濃い場
合、硫化ソーダ廃液を多量に無害化処理できることであ
る。For the reasons described above, one or both of the two liquids can be widely applied from concentrated liquids to low concentrations, and the waste liquid processing method according to the present invention can be reasonably processed. In particular,
When the sodium sulfide waste liquid is thicker than the copper plate etching waste liquid, a large amount of the sodium sulfide waste liquid can be detoxified.
【００２２】更に、本反応は硫化ソーダの中和反応であ
りながら、Ｃｕ2+が反応系に存在する限り、硫化銅の沈
澱反応が優先し、硫化水素の発生を認めることはない。
もっとも、硫化水素ガスの発生を抑制してより安定性の
高い操業を行うには、本反応は酸性側に維持するのがよ
い。Further, although this reaction is a neutralization reaction of sodium sulfide, as long as Cu 2+ is present in the reaction system, the precipitation reaction of copper sulfide has priority and hydrogen sulfide generation is not recognized.
However, in order to suppress the generation of hydrogen sulfide gas and perform a more stable operation, it is preferable to maintain this reaction on the acidic side.
【００２３】従って、反応系の酸化還元電位を測定する
ことにより、安全に操作でき、かつ反応終点を知ること
ができる。Therefore, by measuring the redox potential of the reaction system, it is possible to operate safely and to know the end point of the reaction.
【００２４】反応終了後、暫時熟成してから、濾過また
は遠心分離等による固液分離を行い、沈澱物は洗浄及び
乾燥して硫化銅の有価成分として回収し、これを銅の冶
金原料として再利用することができる。After the completion of the reaction, the mixture is aged for a while, and solid-liquid separation is performed by filtration or centrifugation. The precipitate is washed and dried to recover a valuable component of copper sulfide, which is reused as a metallurgical raw material for copper. Can be used.
【００２５】他方、分離液は食塩水であり、必要に応じ
中和後安全に放流させることができる。すなわち、銅板
エッチング廃液中に塩化第２銅のほかに若干含有する重
金属イオンその他の不純物は全て硫化銅の沈澱と共に硫
化物として沈澱し、またはこの沈澱物に吸着し、かつこ
の硫化物は溶解度が極めて小さいことから、分離液は有
害金属イオンの存在を実質的に認めない。On the other hand, the separated liquid is saline, which can be safely discharged after neutralization if necessary. That is, all the heavy metal ions and other impurities slightly contained in the copper plate etching waste liquid in addition to cupric chloride precipitate as sulfides with the precipitation of copper sulfide, or are adsorbed to this precipitate, and the solubility of this sulfide is Since it is extremely small, the separated liquid practically does not recognize the presence of harmful metal ions.
【００２６】かくして、本発明に係る方法によれば、こ
れまで処理が困難であった硫化ソーダ及び銅板エッチン
グの両廃液を同時かつ一挙に無害化処理が可能となるの
みならず、銅有価成分として回収できる。Thus, according to the method of the present invention, not only the waste liquids of sodium sulfide and copper plate etching, which have been difficult to treat up to now, can be detoxified simultaneously and all at once, but also as valuable copper components. Can be collected.
【００２７】[0027]
【作用】本発明は、硫化ソーダ廃液と銅板エッチング廃
液とを混合処理して両液を無害化すると共に銅有価成分
の回収を図ることにある。According to the present invention, the sodium sulfide waste liquid and the copper plate etching waste liquid are mixed and treated to render both liquids harmless and to recover valuable copper components.
【００２８】上記混合処理において、次式の主反応が生
じる： Ｎａ2Ｓ＋ＣｕＣｌ2→２ＮａＣｌ＋ＣｕＳ↓ (４)In the above mixing process, the main reaction of the following formula occurs: Na 2 S + CuCl 2 → 2NaCl + CuS ↓ (4)
【００２９】また、銅板エッチング廃液中のＣｕ2+以外
の重金属イオンは(４)式の反応と同様に硫化物として沈
澱すると共に他の溶存する不純物もこの沈澱物に実質的
に吸着される。すなわち、銅板エッチング廃液は遊離塩
酸を含有するから、硫化ソーダ廃液との中和の際、次式 Ｎａ2Ｓ＋２ＨＣｌ→２ＮａＣｌ＋Ｈ2Ｓ (５) の反応により硫化水素ガスが発生するはずであるが、反
応系にＣｕ2+等の重金属イオンが溶存している限り、 Ｍｅ2+＋Ｓ2-→ＭｅＳ↓ (６) (式中、Ｍｅ2+はＣｕ2+、Ｎｉ2+、Ｚｎ2+などを表す)の
反応によって全て極めて溶解度の小さい金属硫化物とし
て沈澱する。結局、本発明に係る方法では、実質的に
(５)式のような硫化水素ガスの発生を認めることなく、
極めて化学量論的かつ迅速に無害な食塩水と硫化銅を主
組成とする有価物を生成せしめる。回収した硫化銅は銅
の製錬原料として銅資源のリサイクルの一助とすること
ができる。Heavy metal ions other than Cu 2+ in the copper plate etching waste liquid precipitate as sulfides as in the reaction of the formula (4), and other dissolved impurities are also substantially adsorbed to the precipitates. That is, since the copper plate etching waste liquid contains free hydrochloric acid, hydrogen sulfide gas should be generated by the reaction of the following formula Na 2 S + 2HCl → 2NaCl + H 2 S (5) during neutralization with the sodium sulfide waste liquid. As long as heavy metal ions such as Cu 2+ are dissolved in the system, Me 2+ + S 2- → MeS ↓ (6) (In the formula, Me 2+ represents Cu 2+ , Ni 2+ , Zn 2+, etc. All of them precipitate as metal sulfides having extremely low solubility. After all, in the method according to the present invention,
Without observing the generation of hydrogen sulfide gas as in formula (5),
Extremely stoichiometrically and quickly produce harmless saline solution and valuables mainly composed of copper sulfide. The recovered copper sulfide can be used as a smelting raw material for copper and can be an aid to the recycling of copper resources.
【００３０】[0030]
実施例１ バリウム塩の製造工程から副生する硫化ソーダ廃液(Ｎ
ａ2Ｓ：０.４５％)２０００重量部と、銅板エッチング
廃液(ＣｕＣｌ2：２２.５２％、Ｆ−ＨＣｌ：１.５７
％、Ｚｎ2+：８０.５ｐｐｍ、Ｍｎ2+：０.２１ｐｐｍ、
Ｎｉ2+：５４.４ｐｐｍ、Ｃｒ3+：０.１５ｐｐｍ、
Ｆ-：２７ｐｐｍ、ＣＯＤ：７８ｐｐｍ)６９重量部とを
反応容器に同時添加して撹拌しながら混合処理した。Example 1 Sodium sulfide waste liquid (N
a 2 S: 0.45%) and 2000 parts by weight, the copper plate etching waste liquid (CuCl 2: 22.52%, F -HCl: 1.57
%, Zn 2+ : 80.5 ppm, Mn 2+ : 0.21 ppm,
Ni 2+ : 54.4 ppm, Cr 3+ : 0.15 ppm,
F − : 27 ppm, COD: 78 ppm) (69 parts by weight) were simultaneously added to the reaction vessel, and mixed with stirring.
【００３１】この混合による反応は室温にて系の酸化還
元電位を１００〜０ｍＶの間に維持してｐＨを酸性側に
保持して行ったが、反応終了までＨ2Ｓガスは殆ど発生
せず、安全に廃液処理が操作できた。次いで、処理液を
ｐＨ６.８に中和して濾過分離し、沈澱物を洗浄及び乾
燥して回収した。The reaction by this mixing was carried out at room temperature while maintaining the redox potential of the system between 100 and 0 mV and keeping the pH on the acidic side, but H 2 S gas was scarcely generated until the reaction was completed. I was able to operate the waste liquid treatment safely. Then, the treated liquid was neutralized to pH 6.8, separated by filtration, and the precipitate was washed and dried to collect.
【００３２】分離母液には、重金属イオンと還元性物質
は殆ど検出されず、食塩水のみであったので、これを希
釈して放流することができた。一方、回収した硫化銅粉
末は銅製錬工場へ冶金原料として送ることができた。In the separated mother liquor, heavy metal ions and reducing substances were scarcely detected, and only saline was used. Therefore, it was possible to dilute and discharge this. On the other hand, the recovered copper sulfide powder could be sent to the copper smelting factory as a metallurgical raw material.
【００３３】[0033]
【発明の効果】本発明に係る方法によれば、各種産業界
から廃出される代表的な硫化ソーダ廃液及び銅板エッチ
ング廃液の両液を同時かつ一挙に無害化処理できるのみ
ならず、銅有価成分として合理的に回収することができ
る。特に、硫化ソーダ廃液の処理に当たり、硫化水素ガ
スの実質的な発生をみることなく行うことができること
は、従来法に係る処理の困難性と多大な費用を鑑みると
き、本発明に係る方法の工業的意義は誠に大きなものと
言えよう。EFFECTS OF THE INVENTION According to the method of the present invention, not only the representative sodium sulfide waste liquid and copper plate etching waste liquid discharged from various industries can be detoxified simultaneously but also the valuable copper component Can be reasonably recovered as. In particular, in treating the sodium sulfide waste liquid, it can be carried out without seeing the substantial generation of hydrogen sulfide gas, when considering the difficulty and great cost of the treatment according to the conventional method, the industrial process of the present invention It can be said that its significance is extremely large.
フロントページの続き (72)発明者 宇野 幸光 東京都江東区亀戸９丁目15番１号 日本化 学工業株式会社研究開発本部内Front page continuation (72) Inventor Komitsu Uno 9-15-1, Kameido, Koto-ku, Tokyo Nihon Kagaku Kogyo Co., Ltd.
Claims (2)
を混合、反応させて硫化銅として回収処理することを特
徴とする産業廃液の処理方法。1. A method for treating industrial waste liquid, which comprises mixing and reacting a sodium sulfide waste liquid and a copper plate etching waste liquid to recover copper sulfide as a treatment.
ら発生するものである請求項１記載の産業廃液の処理方
法。2. The method for treating industrial waste liquid according to claim 1, wherein the sodium sulfide waste liquid is generated from the barium salt production process.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10087791A JP3171605B2 (en) | 1991-05-02 | 1991-05-02 | Industrial waste liquid treatment method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10087791A JP3171605B2 (en) | 1991-05-02 | 1991-05-02 | Industrial waste liquid treatment method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0616421A true JPH0616421A (en) | 1994-01-25 |
| JP3171605B2 JP3171605B2 (en) | 2001-05-28 |
Family
ID=14285556
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP10087791A Expired - Fee Related JP3171605B2 (en) | 1991-05-02 | 1991-05-02 | Industrial waste liquid treatment method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3171605B2 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002020480A (en) * | 2000-07-03 | 2002-01-23 | Mitsubishi Gas Chem Co Inc | Process for producing polyphenylene ether |
| CN113264548A (en) * | 2021-05-31 | 2021-08-17 | 王水平 | Method and device for recovering copper and molybdenum by combined treatment of molybdenum removal slag and waste alkaline etching solution |
-
1991
- 1991-05-02 JP JP10087791A patent/JP3171605B2/en not_active Expired - Fee Related
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002020480A (en) * | 2000-07-03 | 2002-01-23 | Mitsubishi Gas Chem Co Inc | Process for producing polyphenylene ether |
| CN113264548A (en) * | 2021-05-31 | 2021-08-17 | 王水平 | Method and device for recovering copper and molybdenum by combined treatment of molybdenum removal slag and waste alkaline etching solution |
Also Published As
| Publication number | Publication date |
|---|---|
| JP3171605B2 (en) | 2001-05-28 |
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