JPH01148388A - Treatment of thick alkali solution - Google Patents
Treatment of thick alkali solutionInfo
- Publication number
- JPH01148388A JPH01148388A JP30409587A JP30409587A JPH01148388A JP H01148388 A JPH01148388 A JP H01148388A JP 30409587 A JP30409587 A JP 30409587A JP 30409587 A JP30409587 A JP 30409587A JP H01148388 A JPH01148388 A JP H01148388A
- Authority
- JP
- Japan
- Prior art keywords
- magnesium
- alkaline solution
- concentrated alkaline
- soln
- compd
- 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
- 239000003513 alkali Substances 0.000 title abstract description 9
- 229910001385 heavy metal Inorganic materials 0.000 claims abstract description 29
- CPLXHLVBOLITMK-UHFFFAOYSA-N magnesium oxide Inorganic materials [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 claims abstract description 7
- TWRXJAOTZQYOKJ-UHFFFAOYSA-L Magnesium chloride Chemical compound [Mg+2].[Cl-].[Cl-] TWRXJAOTZQYOKJ-UHFFFAOYSA-L 0.000 claims abstract description 6
- CSNNHWWHGAXBCP-UHFFFAOYSA-L Magnesium sulfate Chemical compound [Mg+2].[O-][S+2]([O-])([O-])[O-] CSNNHWWHGAXBCP-UHFFFAOYSA-L 0.000 claims abstract description 6
- 239000000395 magnesium oxide Substances 0.000 claims abstract description 6
- 238000000926 separation method Methods 0.000 claims abstract description 6
- AXZKOIWUVFPNLO-UHFFFAOYSA-N magnesium;oxygen(2-) Chemical compound [O-2].[Mg+2] AXZKOIWUVFPNLO-UHFFFAOYSA-N 0.000 claims abstract description 5
- ZLNQQNXFFQJAID-UHFFFAOYSA-L magnesium carbonate Chemical compound [Mg+2].[O-]C([O-])=O ZLNQQNXFFQJAID-UHFFFAOYSA-L 0.000 claims abstract description 3
- 239000001095 magnesium carbonate Substances 0.000 claims abstract description 3
- 229910000021 magnesium carbonate Inorganic materials 0.000 claims abstract description 3
- 229910001629 magnesium chloride Inorganic materials 0.000 claims abstract description 3
- VTHJTEIRLNZDEV-UHFFFAOYSA-L magnesium dihydroxide Chemical compound [OH-].[OH-].[Mg+2] VTHJTEIRLNZDEV-UHFFFAOYSA-L 0.000 claims abstract description 3
- 239000000347 magnesium hydroxide Substances 0.000 claims abstract description 3
- 229910001862 magnesium hydroxide Inorganic materials 0.000 claims abstract description 3
- 229910052943 magnesium sulfate Inorganic materials 0.000 claims abstract description 3
- 235000019341 magnesium sulphate Nutrition 0.000 claims abstract description 3
- 239000012670 alkaline solution Substances 0.000 claims description 25
- 150000002681 magnesium compounds Chemical class 0.000 claims description 13
- 238000000034 method Methods 0.000 claims description 13
- 239000007788 liquid Substances 0.000 claims description 11
- 150000002500 ions Chemical class 0.000 abstract description 10
- 238000006243 chemical reaction Methods 0.000 abstract description 5
- 239000011777 magnesium Substances 0.000 abstract description 5
- 239000002244 precipitate Substances 0.000 abstract description 5
- 238000006386 neutralization reaction Methods 0.000 abstract description 2
- 239000006228 supernatant Substances 0.000 abstract description 2
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 abstract 3
- 229910052749 magnesium Inorganic materials 0.000 abstract 3
- 239000010949 copper Substances 0.000 description 8
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 3
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 description 3
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 3
- 239000002738 chelating agent Substances 0.000 description 3
- KRKNYBCHXYNGOX-UHFFFAOYSA-N citric acid Chemical compound OC(=O)CC(O)(C(O)=O)CC(O)=O KRKNYBCHXYNGOX-UHFFFAOYSA-N 0.000 description 3
- 229910052802 copper Inorganic materials 0.000 description 3
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 2
- JPVYNHNXODAKFH-UHFFFAOYSA-N Cu2+ Chemical compound [Cu+2] JPVYNHNXODAKFH-UHFFFAOYSA-N 0.000 description 2
- RGHNJXZEOKUKBD-SQOUGZDYSA-N D-gluconic acid Chemical compound OC[C@@H](O)[C@@H](O)[C@H](O)[C@@H](O)C(O)=O RGHNJXZEOKUKBD-SQOUGZDYSA-N 0.000 description 2
- OFOBLEOULBTSOW-UHFFFAOYSA-N Malonic acid Chemical compound OC(=O)CC(O)=O OFOBLEOULBTSOW-UHFFFAOYSA-N 0.000 description 2
- FEWJPZIEWOKRBE-UHFFFAOYSA-N Tartaric acid Natural products [H+].[H+].[O-]C(=O)C(O)C(O)C([O-])=O FEWJPZIEWOKRBE-UHFFFAOYSA-N 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 2
- 150000004696 coordination complex Chemical class 0.000 description 2
- 229910001431 copper ion Inorganic materials 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-M hydroxide Chemical compound [OH-] XLYOFNOQVPJJNP-UHFFFAOYSA-M 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 238000004381 surface treatment Methods 0.000 description 2
- 239000011975 tartaric acid Substances 0.000 description 2
- 235000002906 tartaric acid Nutrition 0.000 description 2
- 239000002351 wastewater Substances 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 1
- 239000005749 Copper compound Substances 0.000 description 1
- RGHNJXZEOKUKBD-UHFFFAOYSA-N D-gluconic acid Natural products OCC(O)C(O)C(O)C(O)C(O)=O RGHNJXZEOKUKBD-UHFFFAOYSA-N 0.000 description 1
- FEWJPZIEWOKRBE-JCYAYHJZSA-N Dextrotartaric acid Chemical compound OC(=O)[C@H](O)[C@@H](O)C(O)=O FEWJPZIEWOKRBE-JCYAYHJZSA-N 0.000 description 1
- 229910004028 SiCU Inorganic materials 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- GSEJCLTVZPLZKY-UHFFFAOYSA-N Triethanolamine Chemical compound OCCN(CCO)CCO GSEJCLTVZPLZKY-UHFFFAOYSA-N 0.000 description 1
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 229910021529 ammonia Inorganic materials 0.000 description 1
- 150000001450 anions Chemical class 0.000 description 1
- 229910052804 chromium Inorganic materials 0.000 description 1
- 239000011651 chromium Substances 0.000 description 1
- 235000015165 citric acid Nutrition 0.000 description 1
- 150000001880 copper compounds Chemical class 0.000 description 1
- 230000018044 dehydration Effects 0.000 description 1
- 238000006297 dehydration reaction Methods 0.000 description 1
- 239000000174 gluconic acid Substances 0.000 description 1
- 235000012208 gluconic acid Nutrition 0.000 description 1
- 150000004679 hydroxides Chemical class 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000007517 polishing process Methods 0.000 description 1
- 238000001556 precipitation Methods 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 239000011701 zinc Substances 0.000 description 1
- 229910052725 zinc Inorganic materials 0.000 description 1
Landscapes
- Removal Of Specific Substances (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は濃厚アルカリ液中の重金属を分離する濃厚アル
カリ液の処理方法に関するものである。DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for treating a concentrated alkaline solution for separating heavy metals from the concentrated alkaline solution.
表面処理工程などから、銅化合物などの重金属類を含む
濃厚アルカリ液が排出されることがある。Concentrated alkaline liquid containing heavy metals such as copper compounds may be discharged from surface treatment processes.
従来、このような濃厚アルカリ液から重金属イオンを分
離することは困難をきわめており、多くの場合、そのま
〜中和し【処分されていた。Conventionally, it has been extremely difficult to separate heavy metal ions from such concentrated alkaline solutions, and in many cases they have been neutralized or disposed of.
アルカリの濃度が５％以上となるような濃厚アルカリ液
においてはｐＨが１４を超えてしまい、このような環境
下では、一般的な重金属錯体含有水の場合と異なり、水
酸化物を形成させるべく薬剤を添加しても、生成した水
酸化物がアルカリによりてイオン化し、再溶解してしま
５からである。In a concentrated alkaline solution with an alkali concentration of 5% or more, the pH will exceed 14, and in such an environment, unlike in the case of general heavy metal complex-containing water, it is difficult to form hydroxides. Even if a chemical is added, the generated hydroxide is ionized by the alkali and redissolved5.
一力。One power.
とな士＊癩一般的な重金属錯体を含む廃水の処理方法と
してマグネシウム化合物を添加して処理する方法は本出
願人が先に特願昭６０−３４０８６号として提案した。The present applicant previously proposed a method for treating wastewater containing heavy metal complexes by adding a magnesium compound in Japanese Patent Application No. 60-34086.
しかし、前記提案方法においてはマグネシウム化合物添
加後のｐＨは１０〜１２に調整しなければならず、ｐＨ
が１２を超えると一旦沈殿した重金属類が分散、再溶解
して処理効率が極めて悪くなり、実際的ではなくなって
しまうという認識があった。However, in the proposed method, the pH after adding the magnesium compound must be adjusted to 10 to 12, and the pH
It has been recognized that if the value exceeds 12, the heavy metals that have precipitated will be dispersed and redissolved, resulting in extremely poor treatment efficiency, making it impractical.
従って、ｐＨが１４を超えるような濃厚アルカリ液中の
重金属類の分離方法として、マグネシウム化合物を適用
することは、前記の認識に反し、事実かって提案された
ことはなく、前述のとおり単に中和して処分されるのみ
であった。Therefore, contrary to the above-mentioned recognition, the application of magnesium compounds as a method for separating heavy metals in concentrated alkaline solutions with a pH exceeding 14 has never been proposed; They were only disposed of.
本発明は、このような濃厚アルカリ液中の重金属を分離
し、必要に応じて濃厚アルカリ液を再利用することがで
きるような技術の開発をめざし、鋭意研究が続けられた
結果完成されたものである。The present invention was completed as a result of intensive research aimed at developing a technology that can separate heavy metals from such concentrated alkaline liquid and reuse the concentrated alkaline liquid as needed. It is.
即ち、本発明は重金属を含む濃厚アルカリ液にマグネシ
ウム化合物を添加して固液分離することを特徴とする濃
厚アルカリ液の処理方法である。That is, the present invention is a method for treating a concentrated alkaline solution, which is characterized by adding a magnesium compound to a concentrated alkaline solution containing heavy metals and performing solid-liquid separation.
本発明の対象とする濃厚アルカリ液としては、アルカリ
の濃度が５重量％な超え、ｐＨでは１４を超えてしまう
よ５な濃厚アルカリ液が挙げられる。The concentrated alkaline solution targeted by the present invention includes a concentrated alkaline solution with an alkali concentration of more than 5% by weight and a pH of more than 14.
アルカリとしては水酸化ナトリウム、水酸化カリウムな
ど強アルカリ性物質が挙げられる。Examples of the alkali include strong alkaline substances such as sodium hydroxide and potassium hydroxide.
一方、この濃厚アルカリ液に含まれる重金属としては、
銅、亜鉛、クロム及びアルミニウムなどが挙げられる。On the other hand, the heavy metals contained in this concentrated alkaline solution are:
Examples include copper, zinc, chromium and aluminum.
このような重金属を含む濃厚アルカリ液としては、メッ
ギ剥離工程や電解研磨工程などの各種表面処理工程廃水
などが例示されるが、これに限られることはない。Examples of such a concentrated alkaline solution containing heavy metals include, but are not limited to, wastewater from various surface treatment processes such as Meggi peeling process and electrolytic polishing process.
なお、本発明において、重金属はクエン酸、酒石酸、グ
ルコン酸、マロン酸、トリエタノールアミン及びアンモ
ニアなどのキレート剤とともに存在していてもよい。但
し、このようなキレート剤と共存していても重金属錯体
を形成することはなく、前述の理由で重金属は陰イオン
として存在している。例えば鋼を例にとると、Ｃｕ”＋
２０Ｈ″″シＣｕ （ＯＨｈ↓Ｃｕ （ＯＨ）黛＋
２０）ｒ−−ＣｕＯｒ＋ ２ Ｈ＊０となる。In addition, in the present invention, the heavy metal may be present together with a chelating agent such as citric acid, tartaric acid, gluconic acid, malonic acid, triethanolamine, and ammonia. However, even if such a chelating agent coexists, a heavy metal complex is not formed, and the heavy metal exists as an anion for the above-mentioned reason. For example, taking steel as an example, Cu”+
20H″″SiCu (OHh↓Cu (OH) Mayuzumi+
20) r--CuOr+ 2 H*0.
このような濃厚アルカリ液中の重金属イオンを沈殿分離
するためにマグネシウム化合物を加える。A magnesium compound is added to precipitate and separate heavy metal ions in such a concentrated alkaline solution.
本発明に用いられるマグネシウム化合物としては、酸化
マグネシウム、水酸化マグネシウム、炭酸マグネシウム
、塩化マグネシウム、硫酸マグネシウムなどが挙げられ
るが、これらに限られず、要は高アルカリ条件下で重金
属イオンと反応して不溶性化合物を形成するものであれ
ばよい。Examples of the magnesium compound used in the present invention include magnesium oxide, magnesium hydroxide, magnesium carbonate, magnesium chloride, magnesium sulfate, etc., but are not limited to these.In short, they react with heavy metal ions under highly alkaline conditions and become insoluble. Any material that forms a compound may be used.
なお、前記例のうち、酸化マグネシウムは粉末状粒子で
あり、そのま〜使用するとアルカリ性下では溶解しＫ＜
＜、酸化マグネシウム粒子の表面のみがイオン化し、そ
こで重金属イオンと反応する。このため、沈殿分離やそ
の後の脱水が容易になるうえ、特に処理済の濃厚アルカ
リ液を再利用する場合には、アルカリ液中に余計なイオ
ンを持ち込むことがないので好ましい。In addition, in the above examples, magnesium oxide is a powdery particle, and when used as is, it dissolves in alkaline conditions and K<
<, Only the surface of the magnesium oxide particles is ionized and reacts there with heavy metal ions. For this reason, precipitation separation and subsequent dehydration are facilitated, and particularly when the treated concentrated alkaline solution is reused, unnecessary ions are not introduced into the alkaline solution, which is preferable.
以上のように重金属を含む濃厚アルカリ液にマグネシウ
ム化合物を添加すると、重金属イオンとマグネシウム化
合物が下式のように反応する（前述の銅の例）。As described above, when a magnesium compound is added to a concentrated alkaline solution containing heavy metals, the heavy metal ions and the magnesium compound react as shown in the following formula (the above-mentioned copper example).
Ｃｕ０ｒ＋Ｍｇ！＋ＭｇＣｕ０ｍ↓
このような高アルカリ性下における重金属イオンとマグ
ネシウム化合物の直接反応による沈殿生成法は従来知ら
れていなかったものである。Cu0r+Mg! +MgCu0m↓ A method of forming a precipitate by direct reaction of heavy metal ions and a magnesium compound under such highly alkaline conditions has not been previously known.
マグネシウム化合物の添加量は上述の反応式からも明ら
かなように重金属イオンとの反応当量以上とする。As is clear from the above reaction formula, the amount of the magnesium compound added should be at least the reaction equivalent with the heavy metal ion.
こうして生成した沈殿物は公知の固液分離手段により濃
厚アルカリ液から分離すればよい。The precipitate thus generated may be separated from the concentrated alkaline solution by a known solid-liquid separation means.
分離した沈殿物は別途脱水後処分する。一方、上澄液で
ある濃厚アルカリ液は中和後部分してもよいが、十分精
製されているので再使用することが可能である。The separated precipitate is separately dehydrated and then disposed of. On the other hand, the concentrated alkaline liquid, which is the supernatant liquid, may be kept as a portion after neutralization, but since it is sufficiently purified, it can be reused.
濃厚アルカリ液中に存在する重金属はキレート剤が存在
していても下式のように大部分がイオン状となって存在
している（銅の例を示す）。Even if a chelating agent is present, most of the heavy metals present in a concentrated alkaline solution exist in an ionic form as shown in the formula below (copper is shown as an example).
Ｃｕ”＋２０Ｈ−Ｃｕ（ＯＨ）ｚ↓
Ｃｕ（ＯＨ）鵞＋２０Ｈ−Ｃｕ０ｒ＋２ＨｔＯこのよう
な液にマグネシウム化合物を添加すると下式の反応に従
って重金属の難溶性塩を形成する。Cu"+20H-Cu(OH)z↓ Cu(OH)+20H-Cu0r+2HtO When a magnesium compound is added to such a liquid, a sparingly soluble salt of a heavy metal is formed according to the reaction of the following formula.
Ｃｕ０ｊ ＋Ｍｇ’ ＭｇＣｕＯ＊↓この化合物は極
めて安定であり、濃厚アルカリ液中においても再溶解す
ることはない。Cu0j +Mg' MgCuO*↓This compound is extremely stable and will not be redissolved even in concentrated alkaline solution.
以下に本発明の実施例を揚げてさらに本発明を説明する
。The present invention will be further explained below with reference to Examples.
銅イオン２００ｍｆ／ｌ、酒石酸５００１ｔｙｉ／ｌ及
び水酸化す） ＩＪウム１０重量％をそれぞれ含む濃厚
アルカリ液に、ＭｇＯをｘｏ９／ｌ添加し、０．５時間
攪拌を行なった。To a concentrated alkaline solution containing 200 mf/l of copper ions, 5001 tyi/l of tartaric acid, and 10% by weight of IJium hydroxide, xo9/l of MgO was added and stirred for 0.5 hours.
その後、ｆｆｌｓＡＰ紙を用いて固液分離を行ない、Ｆ
液中の銅イオン濃度を測定したところ、１キ／ｌ以下で
あった。After that, solid-liquid separation was performed using fflsAP paper, and F
When the copper ion concentration in the liquid was measured, it was less than 1 K/l.
これかられかるように、本発明方法は濃厚アルカリ液中
の重金属イオンを効率良く分離することができる。As will be seen, the method of the present invention can efficiently separate heavy metal ions in a concentrated alkaline solution.
本発明は、濃厚アルカリ液中の重金属類を極めて効率よ
く分離することができる。また、得られた濃厚アルカリ
液は再利用することができ、経済的に大きな利益をもた
らすという著しい効果を特徴する
特許出願人 栗田工業株式会社INDUSTRIAL APPLICATION This invention can separate heavy metals in a concentrated alkaline solution very efficiently. In addition, the obtained concentrated alkaline solution can be reused, resulting in significant economic benefits.Patent applicant: Kurita Water Industries, Ltd.
Claims (1)
を添加して固液分離することを特徴とする濃厚アルカリ
液の処理方法。 ２）濃厚アルカリ液が５重量％以上の濃度のものである
特許請求の範囲第１項記載の処理方法。 ３）マグネシウム化合物が酸化マグネシウム、水酸化マ
グネシウム、炭酸マグネシウム、塩化マグネシウム、ま
たは硫酸マグネシウムである特許請求の範囲第１項又は
第２項記載の処理方法。[Scope of Claims] 1) A method for treating a concentrated alkaline solution, which comprises adding a magnesium compound to a concentrated alkaline solution containing heavy metals and performing solid-liquid separation. 2) The treatment method according to claim 1, wherein the concentrated alkaline solution has a concentration of 5% by weight or more. 3) The treatment method according to claim 1 or 2, wherein the magnesium compound is magnesium oxide, magnesium hydroxide, magnesium carbonate, magnesium chloride, or magnesium sulfate.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62304095A JP2623616B2 (en) | 1987-12-01 | 1987-12-01 | Treatment of concentrated alkaline solution |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62304095A JP2623616B2 (en) | 1987-12-01 | 1987-12-01 | Treatment of concentrated alkaline solution |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH01148388A true JPH01148388A (en) | 1989-06-09 |
| JP2623616B2 JP2623616B2 (en) | 1997-06-25 |
Family
ID=17928963
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62304095A Expired - Lifetime JP2623616B2 (en) | 1987-12-01 | 1987-12-01 | Treatment of concentrated alkaline solution |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2623616B2 (en) |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5533952A (en) * | 1978-08-31 | 1980-03-10 | Murata Mach Ltd | Gear box |
| JPS59166290A (en) * | 1983-03-10 | 1984-09-19 | Unitika Ltd | Method for removing harmful component in waste water of smoke scrubbing |
| JPS61192386A (en) * | 1985-02-22 | 1986-08-26 | Kurita Water Ind Ltd | Treatment of waste water containing heavy metal complex |
-
1987
- 1987-12-01 JP JP62304095A patent/JP2623616B2/en not_active Expired - Lifetime
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5533952A (en) * | 1978-08-31 | 1980-03-10 | Murata Mach Ltd | Gear box |
| JPS59166290A (en) * | 1983-03-10 | 1984-09-19 | Unitika Ltd | Method for removing harmful component in waste water of smoke scrubbing |
| JPS61192386A (en) * | 1985-02-22 | 1986-08-26 | Kurita Water Ind Ltd | Treatment of waste water containing heavy metal complex |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2623616B2 (en) | 1997-06-25 |
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