JP2000202445A - Treatment of recovered water containing fluoride ion in semiconductor production process - Google Patents
Treatment of recovered water containing fluoride ion in semiconductor production processInfo
- Publication number
- JP2000202445A JP2000202445A JP11006666A JP666699A JP2000202445A JP 2000202445 A JP2000202445 A JP 2000202445A JP 11006666 A JP11006666 A JP 11006666A JP 666699 A JP666699 A JP 666699A JP 2000202445 A JP2000202445 A JP 2000202445A
- Authority
- JP
- Japan
- Prior art keywords
- water
- scale
- recovered water
- treatment
- sodium
- 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.)
- Pending
Links
Landscapes
- Separation Using Semi-Permeable Membranes (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明はフッ化物イオンを含
む半導体製造工程回収水の処理方法に係り、特に、フッ
化物イオンを含む半導体製造工程回収水を再利用するに
当り、超純水製造装置の逆浸透（ＲＯ）膜装置における
フッ化カルシウムスケールの生成を防止して、処理水
量、処理効率の向上及び処理の安定化を図る方法に関す
る。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for treating recovered water from a semiconductor manufacturing process containing fluoride ions, and more particularly, to an apparatus for producing ultrapure water when recycling recovered water from a semiconductor manufacturing process containing fluoride ions. The present invention relates to a method for preventing the generation of calcium fluoride scale in a reverse osmosis (RO) membrane device, thereby improving the amount of treated water, the treatment efficiency, and stabilizing the treatment.
【０００２】[0002]
【従来の技術】半導体工場では、水の有効利用率を高め
るために、各種排水を分別して回収し、超純水製造装置
で処理して超純水として再利用することが行われてい
る。2. Description of the Related Art In a semiconductor factory, in order to increase the effective utilization rate of water, various kinds of wastewater are separated and collected, treated by an ultrapure water producing apparatus, and reused as ultrapure water.
【０００３】しかし、半導体工場では、製造工程におい
てフッ酸を使用しているため、半導体製造工程回収水に
は微量ではあるがフッ化物イオンが存在する。このフッ
化物イオンは、カルシウムシオンと結合して容易にフッ
化カルシウムを生成する。生成したフッ化カルシウム
は、スケールとして系内に付着するが、このフッ化カル
シウムスケールは容易に除去することはできず、削り取
るなどの物理的処理を行うか、或いは高濃度のＥＤＴＡ
（エチレンジアミンテトラ酢酸）で長時間処理するなど
の処理が必要となる。However, in a semiconductor factory, since hydrofluoric acid is used in the manufacturing process, a small amount of fluoride ions is present in the recovered water in the semiconductor manufacturing process. This fluoride ion combines with calcium cation to easily generate calcium fluoride. The generated calcium fluoride adheres to the system as a scale. However, this calcium fluoride scale cannot be easily removed, and physical treatment such as shaving is performed, or a high concentration of EDTA is used.
(E.g., ethylenediaminetetraacetic acid) for a long time.
【０００４】一方、半導体製造工程回収水を処理する超
純水製造装置に用いられるＲＯ膜装置では、給水が５〜
１０倍に濃縮されるため、給水中のフッ化物イオンやカ
ルシウムイオンが極微量であっても膜面にフッ化カルシ
ウムスケールが析出し、ＲＯ膜が目詰まりすることか
ら、安定処理ができないという問題があった。On the other hand, in an RO membrane apparatus used in an ultrapure water production apparatus for treating recovered water in a semiconductor production process, the supply of water is 5 to 5.
Since it is concentrated 10 times, even if the amount of fluoride ions or calcium ions in the feed water is extremely small, calcium fluoride scales precipitate on the membrane surface, and the RO membrane is clogged, so that a stable treatment cannot be performed. was there.
【０００５】従来、このＲＯ膜装置でのフッ化カルシウ
ムスケールの析出を防止するために、ＲＯ膜装置の前段
に軟化装置を設け、回収水中のカルシウムイオンを予め
除去することが行われている。Conventionally, in order to prevent precipitation of calcium fluoride scale in the RO membrane device, a softening device has been provided in front of the RO membrane device to remove calcium ions in recovered water in advance.
【０００６】[0006]
【発明が解決しようとする課題】しかしながら、軟化装
置におけるカルシウムイオンの除去性能は必ずしも十分
であるとは言えず、微量のカルシウムイオンのリークが
あり、また、運転不良によってもカルシウムイオンがリ
ークする事故が発生する恐れもあった。However, the performance of removing the calcium ions in the softening device is not always sufficient, and there is a leak of a small amount of calcium ions, and an accident in which the calcium ions leak due to poor operation. There was also a risk of occurrence.
【０００７】このため、従来においては、ＲＯ膜装置に
おけるフッ化カルシウムスケールの析出を防止し得ず、
経時による差圧の上昇で処理水量、処理効率が低下する
場合が多かった。Therefore, conventionally, precipitation of calcium fluoride scale in the RO membrane device cannot be prevented,
In many cases, the amount of treated water and the treatment efficiency decreased due to the increase in the differential pressure over time.
【０００８】なお、分離膜の目詰りに対しては、薬品洗
浄等により膜性能を回復させることが考えられるが、Ｒ
Ｏ膜は有機材質よりなり、過酷な洗浄を行うことができ
ず、フッ化カルシウムスケールの析出で目詰りを生じた
場合には、ＲＯ膜を交換する必要があった。In order to prevent clogging of the separation membrane, it is conceivable to recover the membrane performance by chemical cleaning or the like.
The O film is made of an organic material, and cannot be subjected to severe cleaning. When clogging occurs due to precipitation of calcium fluoride scale, it is necessary to replace the RO film.
【０００９】このようなことから、従来においては、フ
ッ化物イオンを含む半導体製造工程回収水については、
多くの場合、超純水製造装置で処理して再利用すること
なく、排水処理を実施して放流しているのが実情であ
る。From the above, conventionally, the recovered water in the semiconductor manufacturing process containing fluoride ions is
In many cases, wastewater is treated and discharged without being treated and reused by an ultrapure water production apparatus.
【００１０】本発明は上記従来の問題点を解決し、フッ
化物イオンを含む半導体製造工程回収水を再利用するに
当り、超純水製造装置のＲＯ膜装置におけるフッ化カル
シウムスケールの生成を確実に防止して、処理水量、処
理効率の向上と処理の安定化を図るフッ化物イオンを含
む半導体製造工程回収水の処理方法を提供することを目
的とする。[0010] The present invention solves the above-mentioned conventional problems and, when recycling recovered water in a semiconductor manufacturing process containing fluoride ions, ensures the generation of calcium fluoride scale in an RO membrane device of an ultrapure water manufacturing device. It is an object of the present invention to provide a method of treating recovered water in a semiconductor manufacturing process containing fluoride ions for improving the amount of treated water, treating efficiency, and stabilizing the treatment.
【００１１】[0011]
【課題を解決するための手段】本発明のフッ化物イオン
を含む半導体製造工程回収水の処理方法は、フッ化物イ
オンを含む半導体製造工程回収水に、ヘキサメタリン酸
ナトリウム、トリポリリン酸ナトリウム及びホスホン酸
系化合物よりなる群から選ばれる１種又は２種以上の薬
剤を添加した後、逆浸透膜分離処理することを特徴とす
る。SUMMARY OF THE INVENTION According to the present invention, there is provided a method for treating recovered water in a semiconductor manufacturing process containing fluoride ions, which comprises adding sodium hexametaphosphate, sodium tripolyphosphate and phosphonic acid to the recovered water containing semiconductor ions in a semiconductor manufacturing process. After adding one or more drugs selected from the group consisting of compounds, reverse osmosis membrane separation treatment is performed.
【００１２】スケール分散剤として、ＲＯ膜装置の給水
にヘキサメタリン酸ナトリウム、トリポリリン酸ナトリ
ウム又はホスホン酸系化合物を添加することにより、こ
れらの少量添加でＲＯ膜装置におけるフッ化カルシウム
スケールの生成を効果的に防止することができる。[0012] By adding sodium hexametaphosphate, sodium tripolyphosphate or a phosphonic acid-based compound to the feed water of the RO membrane device as a scale dispersant, the addition of a small amount of these compounds can effectively generate calcium fluoride scale in the RO membrane device. Can be prevented.
【００１３】なお、一般に、スケール分散剤としては、
上記のリン酸系分散剤の他に、ポリアクリル酸ナトリウ
ム等があるが、ポリアクリル酸ナトリウム等の他の分散
剤では低濃度（１０ｐｐｍ以下）添加でのスケール防止
効果が悪いため、本発明では上記特定のリン酸系分散剤
を用いる。[0013] Generally, as a scale dispersant,
In addition to the above-mentioned phosphoric acid-based dispersants, there are sodium polyacrylate and the like. However, other dispersants such as sodium polyacrylate have a poor scale prevention effect when added at a low concentration (10 ppm or less). The above specific phosphoric acid-based dispersant is used.
【００１４】[0014]
【発明の実施の形態】以下に本発明を詳細に説明する。DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.
【００１５】本発明では、フッ化物イオンを含む半導体
製造工程回収水に、ヘキサメタリン酸ナトリウム、トリ
ポリリン酸ナトリウム及びホスホン酸系化合物よりなる
群から選ばれる１種又は２種以上のスケール分散剤を添
加した後、ＲＯ膜分離処理する。In the present invention, one or more scale dispersants selected from the group consisting of sodium hexametaphosphate, sodium tripolyphosphate and phosphonic acid compounds are added to the water recovered in the semiconductor manufacturing process containing fluoride ions. Thereafter, an RO membrane separation process is performed.
【００１６】なお、ホスホン酸系化合物としては、アミ
ノトリメチルホスホン酸（Ｎ（ＣＨ2ＰＯ3Ｈ2）3）や１
−ヒドロキシエチリデン−１，１−ジホスホン酸（ＣＨ
3ＣＯＨ（ＰＯ3Ｈ2）2）が挙げられる。The phosphonic acid compounds include aminotrimethylphosphonic acid (N (CH 2 PO 3 H 2 ) 3 ) and 1
-Hydroxyethylidene-1,1-diphosphonic acid (CH
3 COH (PO 3 H 2 ) 2 ).
【００１７】これらのスケール分散剤は、ＲＯ膜装置の
給水に連続的に添加しても間欠的に添加しても良いが、
その添加量が、過度に多いと薬剤コストが高騰すると共
に水質の低下を引き起こすことから、１０ｐｐｍ以下、
特に１〜５ｐｐｍとするのが好ましい。These scale dispersants may be added continuously or intermittently to the feed water of the RO membrane device.
If the added amount is excessively large, the cost of the drug rises and the water quality is lowered.
In particular, it is preferably 1 to 5 ppm.
【００１８】[0018]
【実施例】以下に実施例及び比較例を挙げて本発明をよ
り具体的に説明する。The present invention will be described more specifically below with reference to examples and comparative examples.
【００１９】実施例１〜３、比較例１，２ 半導体製造工場において、フッ化物イオンを含む半導体
製造工程回収水（濃厚系回収水）について、採水日Ａ，
Ｂ，Ｃで行った水質分析結果は下記表１に示す通りであ
る。Examples 1 to 3 and Comparative Examples 1 and 2 In a semiconductor manufacturing plant, collected water (concentrated system recovered water) in the semiconductor manufacturing process containing fluoride ions was sampled on day A,
The results of water quality analysis performed in B and C are as shown in Table 1 below.
【００２０】[0020]
【表１】 [Table 1]
【００２１】一方、フッ化物イオン濃度及びカルシウム
イオン濃度とフッ化カルシウム（ＣａＦ2）スケールの
析出領域との関係は図３に示す通りであり、濃厚系回収
水がスケール析出条件にあることが明らかである。On the other hand, the relationship between the fluoride ion concentration and the calcium ion concentration and the precipitation area of the calcium fluoride (CaF 2 ) scale is as shown in FIG. 3, and it is clear that the concentrated recovered water is under the scale precipitation conditions. It is.
【００２２】このようなスケール析出条件にある濃厚系
回収水を、図１に示す如く、活性炭塔１、軟化塔２、保
安フィルター３に順次通水した後、ＲＯ膜装置４で濃縮
倍率５倍で処理し、ＲＯ膜装置４の透過水をリンス系回
収原水槽へ送る処理装置において、保安フィルター３の
入口部に分散剤として表２に示すものをそれぞれ５ｐｐ
ｍ注入し（ただし、比較例１では分散剤注入せず）、Ｒ
Ｏ膜装置４の差圧の経時変化を調べ、結果を図２に示し
た。As shown in FIG. 1, the concentrated recovered water under such scale precipitation conditions is sequentially passed through an activated carbon tower 1, a softening tower 2, and a security filter 3. And the permeated water of the RO membrane device 4 is sent to the rinsing-system recovery raw water tank.
m (but no dispersant was injected in Comparative Example 1).
The change with time in the differential pressure of the O membrane device 4 was examined, and the results are shown in FIG.
【００２３】[0023]
【表２】 [Table 2]
【００２４】図２より、分散剤を添加しない比較例１や
分散剤としてポリアクリル酸ナトリウムを注入した比較
例２では、約５〜６ヶ月の運転で差圧が３ｋｇ／ｃｍ2
に上昇しているのに対し、本発明に係るリン酸系スケー
ル分散剤を注入した実施例１〜３では、１年間の運転後
も差圧の上昇は認められず、本発明に係るリン酸系スケ
ール分散剤がＲＯ膜装置におけるスケール析出及びそれ
による差圧上昇の防止に顕著な効果があることがわか
る。FIG. 2 shows that in Comparative Example 1 in which no dispersant was added and Comparative Example 2 in which sodium polyacrylate was injected as a dispersant, the differential pressure was 3 kg / cm 2 after about 5 to 6 months of operation.
On the other hand, in Examples 1 to 3 in which the phosphoric acid scale dispersant according to the present invention was injected, no increase in the differential pressure was observed even after one year of operation, and the phosphoric acid according to the present invention It can be seen that the system scale dispersant has a remarkable effect on the scale deposition in the RO membrane device and the prevention of an increase in the differential pressure due to the deposition.
【００２５】[0025]
【発明の効果】以上詳述した通り、本発明のフッ化物イ
オンを含む半導体製造工程回収水の処理方法によれば、
フッ化物イオンを含む半導体製造工程回収水を再利用す
るに当り、超純水製造装置のＲＯ膜装置におけるフッ化
カルシウムスケールの生成を確実に防止して、処理水
量、処理効率の向上と処理の安定化を図ることができ
る。As described above in detail, according to the method for treating recovered water of a semiconductor manufacturing process containing fluoride ions of the present invention,
In reusing the recovered water in the semiconductor manufacturing process containing fluoride ions, the generation of calcium fluoride scale in the RO membrane device of the ultrapure water manufacturing device is reliably prevented to improve the amount of treated water, the treatment efficiency, and the treatment efficiency. Stabilization can be achieved.
【００２６】このため、本発明によれば、フッ化物イオ
ンを含む半導体製造工程回収水を再利用することがで
き、水の再利用率を高めることができる。Therefore, according to the present invention, the water recovered in the semiconductor manufacturing process containing fluoride ions can be reused, and the water recycling rate can be increased.
【図１】実施例で用いた処理装置を示す系統図である。FIG. 1 is a system diagram showing a processing apparatus used in an embodiment.
【図２】実施例１〜３及び比較例１，２の結果を示すグ
ラフである。FIG. 2 is a graph showing the results of Examples 1 to 3 and Comparative Examples 1 and 2.
【図３】フッ化物イオン濃度及びカルシウムイオン濃度
とフッ化カルシウムスケールの析出領域との関係を示す
グラフである。FIG. 3 is a graph showing a relationship between a fluoride ion concentration and a calcium ion concentration and a deposition region of a calcium fluoride scale.
１ 活性炭塔 ２ 軟化塔 ３ 保安フィルター ４ ＲＯ膜装置 DESCRIPTION OF SYMBOLS 1 Activated carbon tower 2 Softening tower 3 Security filter 4 RO membrane device
─────────────────────────────────────────────────────
────────────────────────────────────────────────── ───
【手続補正書】[Procedure amendment]
【提出日】平成１１年１月２２日（１９９９．１．２
２）[Submission date] January 22, 1999 (1999.1.2
2)
【手続補正１】[Procedure amendment 1]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】０００３[Correction target item name] 0003
【補正方法】変更[Correction method] Change
【補正内容】[Correction contents]
【０００３】しかし、半導体工場では、製造工程におい
てフッ酸を使用しているため、半導体製造工程回収水に
は微量ではあるがフッ化物イオンが存在する。このフッ
化物イオンは、カルシウムイオンと結合して容易にフッ
化カルシウムを生成する。生成したフッ化カルシウム
は、スケールとして系内に付着するが、このフッ化カル
シウムスケールは容易に除去することはできず、削り取
るなどの物理的処理を行うか、或いは高濃度のＥＤＴＡ
（エチレンジアミンテトラ酢酸）で長時間処理するなど
の処理が必要となる。However, in a semiconductor factory, since hydrofluoric acid is used in the manufacturing process, a small amount of fluoride ions is present in the recovered water in the semiconductor manufacturing process. The fluoride ion is readily form calcium fluoride in combination with calcium ion-. The generated calcium fluoride adheres to the system as a scale. However, this calcium fluoride scale cannot be easily removed, and physical treatment such as shaving is performed, or a high concentration of EDTA is used.
(E.g., ethylenediaminetetraacetic acid) for a long time.
───────────────────────────────────────────────────── フロントページの続き Ｆターム(参考） 4D006 GA03 KA02 KA03 KA33 KB11 KB12 KB14 KD19 KD30 KE06P KE11R KE12P KE15P KE19P PA01 PB07 PB08 PB27 PB28 PC02 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 4D006 GA03 KA02 KA03 KA33 KB11 KB12 KB14 KD19 KD30 KE06P KE11R KE12P KE15P KE19P PA01 PB07 PB08 PB27 PB28 PC02
Claims (1)
収水に、ヘキサメタリン酸ナトリウム、トリポリリン酸
ナトリウム及びホスホン酸系化合物よりなる群から選ば
れる１種又は２種以上の薬剤を添加した後、逆浸透膜分
離処理することを特徴とするフッ化物イオンを含む半導
体製造工程回収水の処理方法。1. One or more agents selected from the group consisting of sodium hexametaphosphate, sodium tripolyphosphate and phosphonic acid compounds are added to water recovered in a semiconductor manufacturing process containing fluoride ions, followed by reverse osmosis. A method for treating recovered water in a semiconductor manufacturing process containing fluoride ions, the method comprising performing a membrane separation treatment.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP11006666A JP2000202445A (en) | 1999-01-13 | 1999-01-13 | Treatment of recovered water containing fluoride ion in semiconductor production process |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP11006666A JP2000202445A (en) | 1999-01-13 | 1999-01-13 | Treatment of recovered water containing fluoride ion in semiconductor production process |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JP2000202445A true JP2000202445A (en) | 2000-07-25 |
Family
ID=11644711
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP11006666A Pending JP2000202445A (en) | 1999-01-13 | 1999-01-13 | Treatment of recovered water containing fluoride ion in semiconductor production process |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2000202445A (en) |
Cited By (9)
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|---|---|---|---|---|
| JP2002210335A (en) * | 2001-01-16 | 2002-07-30 | Japan Organo Co Ltd | Apparatus and method for desalting using reverse osmosis membrane |
| WO2013157549A1 (en) * | 2012-04-17 | 2013-10-24 | 栗田工業株式会社 | Reverse osmosis membrane treatment method and reverse osmosis membrane treatment device |
| CN104176865A (en) * | 2014-08-28 | 2014-12-03 | 宁波泽沃水处理科技有限公司 | Pure water treatment device |
| CN104176866A (en) * | 2014-08-28 | 2014-12-03 | 宁波泽沃水处理科技有限公司 | Multifunctional pure water treatment device |
| JP2015058398A (en) * | 2013-09-19 | 2015-03-30 | ダイキン工業株式会社 | Method and apparatus for treating waste water containing organofluorine surfactant |
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| KR20150132571A (en) | 2013-03-22 | 2015-11-25 | 쿠리타 고교 가부시키가이샤 | Method for preventing scale deposition and scale inhibitor |
| CN105110505A (en) * | 2015-08-26 | 2015-12-02 | 湖州升腾环境工程有限公司 | First-stage reverse osmosis device for pretreating and softening |
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-
1999
- 1999-01-13 JP JP11006666A patent/JP2000202445A/en active Pending
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2002210335A (en) * | 2001-01-16 | 2002-07-30 | Japan Organo Co Ltd | Apparatus and method for desalting using reverse osmosis membrane |
| WO2013157549A1 (en) * | 2012-04-17 | 2013-10-24 | 栗田工業株式会社 | Reverse osmosis membrane treatment method and reverse osmosis membrane treatment device |
| JP2013220384A (en) * | 2012-04-17 | 2013-10-28 | Kurita Water Ind Ltd | Method and apparatus for treating reverse osmosis membrane |
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