JPH0142754B2 - - Google Patents
Info
- Publication number
- JPH0142754B2 JPH0142754B2 JP60096193A JP9619385A JPH0142754B2 JP H0142754 B2 JPH0142754 B2 JP H0142754B2 JP 60096193 A JP60096193 A JP 60096193A JP 9619385 A JP9619385 A JP 9619385A JP H0142754 B2 JPH0142754 B2 JP H0142754B2
- Authority
- JP
- Japan
- Prior art keywords
- exchange resin
- water
- anion exchange
- ultrapure water
- polisher
- 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.)
- Expired
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D65/00—Accessories or auxiliary operations, in general, for separation processes or apparatus using semi-permeable membranes
- B01D65/08—Prevention of membrane fouling or of concentration polarisation
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2321/00—Details relating to membrane cleaning, regeneration, sterilization or to the prevention of fouling
- B01D2321/16—Use of chemical agents
- B01D2321/162—Use of acids
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2321/00—Details relating to membrane cleaning, regeneration, sterilization or to the prevention of fouling
- B01D2321/16—Use of chemical agents
- B01D2321/164—Use of bases
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Separation Using Semi-Permeable Membranes (AREA)
- Treatment Of Water By Ion Exchange (AREA)
Description
〔発明の利用分野〕
本発明は半導体製造用および医薬製造用等超純
水製造設備のユースポイント周辺の超純水製造二
次系システムに含まれる膜分離装置の透過膜汚染
防止方法に関するものである。
〔従来技術〕
半導体製造および医薬製造には電解質、微粒
子、生菌等が極めて少ない高度に精製された超高
純度の純水、いわゆる超純水が必要とされてい
る。
近年はこれらの工業の高度化に伴い、さらに入
念に精製され理論値に近い純度をもつた超純水が
要求されている。超純水は通常次図に示されるよ
うなシステムの組合せにより製造されているが、
各システムの機能としては前処理システムはコロ
イド状物質の除去、一次系システムは大半の電解
質、微粒子、生菌等の除去、二次系システムは一
次系システムで得られる高純度の
[Field of Application of the Invention] The present invention relates to a method for preventing contamination of a permeable membrane of a membrane separation device included in a secondary ultrapure water production system around the point of use of ultrapure water production equipment for semiconductor manufacturing, pharmaceutical manufacturing, etc. be. [Prior Art] Semiconductor manufacturing and pharmaceutical manufacturing require highly purified ultra-pure water, so-called ultra-pure water, which contains extremely few electrolytes, fine particles, viable bacteria, and the like. In recent years, with the advancement of these industries, there has been a demand for ultrapure water that has been purified even more carefully and has a purity close to the theoretical value. Ultrapure water is usually produced by a combination of systems as shown in the figure below.
The functions of each system are that the pretreatment system removes colloidal substances, the primary system removes most electrolytes, particulates, viable bacteria, etc., and the secondary system removes the high purity obtained in the primary system.
そこで本発明は超純水製造システムの特に二次
系システムにおける膜分離装置の透過膜の洗浄頻
度を減少させることを目的とする。
〔発明の構成〕
上記目的を達するために本発明では、超純水精
造一次系システムからの高純度純水を、殺菌装
置、ポリシヤー装置、透過膜を内蔵する膜分離装
置の順に通過処理して超純水として供給するよう
に構成された超純水製造二次系システムに於て、
ポリシヤー装置として陰イオン交換樹脂層及び強
塩基性陰イオン交換樹脂と強酸性陽イオン交換樹
脂との混合層からなるポリシヤー装置を使用する
ことにより上記目的を達しようとするものであ
る。
本発明の利用分野である超純水製造工程では上
水、井水、河川水等を原水として、まず原水の水
質に応じて前処理が行なわれる。前処理システム
としては凝集処理、過処理、活性炭処理等を組
合せて実施される。
そして前処理システムを通過した原水は一次系
システムに供給され高純度純水に精製される。
一次系システムは通常の純水製造に適用される
多塔式の純水装置及び混床式純水装置さらにコロ
イド状のシリカを除去するための逆浸透膜装置を
組合せることにより実施される。この一次系シス
テムで大部分の電解質、微粒子、生菌類等が除去
され、一次系システムから流出する高純度純水の
水質としては通常比抵抗10〜15MΩ−cm、微粒子
100〜500個／ml、生菌数10個／ml以下程度が目標
とされる。
一次系システムで製造された高純度純水はつい
で二次系システムに付され一次系システムで捕捉
され得なかつた電解質、微粒子、生菌類等が除去
され超純水に精製される。第１図は本発明が適用
される超純水製造二次系システムのフローダイヤ
グラムである。
図中１は高純度純水タンクで一次系システムで
製造された高純度純水が貯蔵されている。
高純度純水はまず紫外線殺菌装置２に導入され
る。
紫外線殺菌装置２では紫外線の殺菌効果を利用
して高純度純水中のバクテリア等の生菌を殺菌す
るために紫外線が照射され、波長としては260n
ｍ付近、照射量として40000μワツト・秒／cm2程
度が採用されている。
紫外線殺菌された高純度純水は引続いて本発明
が適用されているポリシヤー装置３に導入され
る。
ポリシヤー装置３はほぼ完全に再生された陰イ
オン交換樹脂層及びほぼ完全に再生された強塩基
性陰イオン交換樹脂と強酸性陽イオン交換樹脂と
の混合層からなつている。
高純度純水は陰イオン交換樹脂層から強塩基性
陰イオン交換樹脂と強酸性陽イオン樹脂との混合
層の順に接触し精製されるが、本発明のポリシヤ
ー装置３は従来のポリシヤー装置の強塩基性陰イ
オン交換樹脂と強酸性陽イオン交換樹脂との混合
層の前段にほゞ完全再生された陰イオン交換樹脂
層を設けることを必須の要件としたポリシヤー装
置である。
そのためには強塩基性陰イオン交換樹脂と強酸
性陽イオン交換樹脂との混合層からなるイオン交
換塔の前に陰イオン交換樹脂を充填した新たなイ
オン交換塔を設置する方法、あるいは強塩基性陰
イオン交換樹脂及び強酸性陽イオン交換樹脂を系
外で再生し混合状態にしてカートリツジ式のイオ
ン交換塔に充填し、さらにその上部に系外で再生
した陰イオン交換樹脂を積層させ形成したイオン
交換樹脂層を保持したカートリツジ式にする方法
のいずれをも採用できる。
上述のポリシヤー装置から流出する高純度純水
はさらにポリアクリロニトリル、ポリアミド、ポ
リスルフオン等を主体とした透過膜を内蔵した膜
分離装置４に供給される。
ここではこれまでの諸処理により除去できなか
つた特に微細な非イオン性物質が除去され、流出
する高度に精製された超高純度純水は超純水とし
てユースポイントに供給され利用される。この超
純水の水質は電気伝導度16〜18MΩ−cm、微粒子
数20〜50個／ml以下、生菌数１個／ml以下であ
る。
その際、透過膜の表面には微細な非イオン性物
質が濃縮残留し、圧力損失を増大させることにな
るが、本発明で構成されたポリシヤー装置３を通
過しているので膜分離装置４の圧力損失は大幅に
軽減される。
超純水製造工程の二次系システムに於て、本発
明で構成されたポリシヤー装置を通過させた高純
度純水を膜分離装置に供給すると何故に膜分離装
置の圧力損失が軽減されるかは明確には解明され
ていないが、微細な非イオン性物質は陰イオン交
換樹脂の層を通過することにより透過膜表面に付
着し難い性質に変化し、そのため濃縮水と共に系
外に流出し透過膜汚染が減少するためだと考えら
れ、そしてこの透過膜汚染が減少する現象は特定
の透過膜に対してあらわれるものではない。
本発明でのポリシヤー装置における陰イオン交
換樹脂層において採用される陰イオン交換樹脂と
しては強塩基性、弱塩基性またポーラス形、ゲル
形いずれでも良いが、塩基性度が大であることか
ら強塩基性、耐汚染の面からポーラス形が好まし
い。そして通液速度はSV50〜100hr-1付近が採用
される。
混合層の強塩基性陰イオン交換樹脂と強酸性陽
イオン交換樹脂の混合割合は体積比で強塩基性陰
イオン交換樹脂：強酸性陽イオン交換樹脂＝１：
１〜２：１が採用される。
さらに混合層のイオン交換樹脂としてはゲル形
が採用される。
〔実施例〕
次に実施例を挙げて本発明を説明するが、本発
明は次の実施例に限定されるものではない。
実施例 １
水道水を強酸性陽イオン交換樹脂SK1B（三菱
化成工業株式会社製、以下単にSK1Bと記す。）
を充填した陽イオン交換塔、強塩基性陰イオン交
換樹脂SA10A（三菱化成工業株式会社製、以下単
にSA10Aと記す。）を充填した陰イオン交換塔に
順次通水した後、逆浸透膜SC−3100（東レ株式会
社製）を装備した逆浸透装置で操作圧25Kg／cm2、
回収率85％で処理し、さらにSK1BとSA10Aが
１：２（体積比）の割合の混合樹脂層からなるミ
ツクスベツドポリシヤーに通水して処理を行い流
出水を高純度純水とした。ミツクスベツドポリシ
ヤーの再生レベルはSK1Bについては100ｇ−
HCl／−樹脂、SA10Aについては100ｇ−
NaOH／−樹脂とした。
高純度純水の平均水質は第１表のようであつ
た。
Therefore, an object of the present invention is to reduce the frequency of cleaning a permeable membrane of a membrane separation device in an ultrapure water production system, particularly in a secondary system. [Structure of the Invention] In order to achieve the above object, the present invention passes through and processes high-purity pure water from a primary ultrapure water purification system in the following order: a sterilizer, a polisher, and a membrane separation device incorporating a permeable membrane. In a secondary ultrapure water production system configured to supply ultrapure water using
The above object is achieved by using a polisher device comprising an anion exchange resin layer and a mixed layer of a strongly basic anion exchange resin and a strongly acidic cation exchange resin. In the ultrapure water production process, which is the field of application of the present invention, raw water such as tap water, well water, river water, etc. is first subjected to pretreatment depending on the quality of the raw water. The pretreatment system is implemented by combining coagulation treatment, overtreatment, activated carbon treatment, etc. The raw water that has passed through the pre-treatment system is then supplied to the primary system where it is purified into highly purified water. The primary system is implemented by combining a multi-column type water purification device and a mixed bed type water purification device, which are used for normal pure water production, and a reverse osmosis membrane device for removing colloidal silica. Most electrolytes, particulates, living bacteria, etc. are removed in this primary system, and the quality of the high-purity water flowing out from the primary system is usually 10 to 15 MΩ-cm with a specific resistance of 10 to 15 MΩ-cm and fine particles.
The target is 100 to 500 cells/ml, with a viable count of 10 cells/ml or less. The highly purified water produced in the primary system is then sent to the secondary system, where electrolytes, particulates, viable bacteria, etc. that could not be captured by the primary system are removed and purified to ultrapure water. FIG. 1 is a flow diagram of a secondary ultrapure water production system to which the present invention is applied. In the figure, 1 is a high-purity pure water tank in which high-purity pure water produced in the primary system is stored. High purity water is first introduced into the ultraviolet sterilizer 2. In the ultraviolet sterilizer 2, ultraviolet rays are irradiated to sterilize viable bacteria such as bacteria in high-purity water using the sterilizing effect of ultraviolet rays, and the wavelength is 260n.
m, and an irradiation dose of approximately 40,000 μW/sec/cm 2 is adopted. The ultraviolet sterilized high-purity water is then introduced into the polisher device 3 to which the present invention is applied. The polisher device 3 consists of an almost completely regenerated anion exchange resin layer and an almost completely regenerated mixed layer of a strongly basic anion exchange resin and a strongly acidic cation exchange resin. Highly purified water is purified by contacting the anion exchange resin layer with the mixed layer of a strong basic anion exchange resin and a strong acidic cation resin in this order. This is a polisher device in which an almost completely regenerated anion exchange resin layer is provided upstream of a mixed layer of a basic anion exchange resin and a strongly acidic cation exchange resin. To achieve this, there is a method of installing a new ion exchange tower filled with an anion exchange resin in front of an ion exchange tower consisting of a mixed layer of a strongly basic anion exchange resin and a strongly acidic cation exchange resin, or a method of installing a new ion exchange tower filled with an anion exchange resin, or An ion exchange resin and a strongly acidic cation exchange resin are regenerated outside the system, mixed, and packed into a cartridge-type ion exchange tower, and the anion exchange resin regenerated outside the system is layered on top of the ion exchange tower. Any of the methods of using a cartridge that holds an exchangeable resin layer can be adopted. The high-purity water flowing out from the polisher device described above is further supplied to a membrane separation device 4 having a built-in permeable membrane mainly made of polyacrylonitrile, polyamide, polysulfone, or the like. Here, particularly fine nonionic substances that could not be removed by the various treatments up to now are removed, and the highly purified ultra-high purity water that flows out is supplied to the point of use as ultra-pure water for use. The quality of this ultrapure water is that the electrical conductivity is 16 to 18 MΩ-cm, the number of fine particles is 20 to 50 particles/ml or less, and the number of viable bacteria is 1 particle/ml or less. At this time, fine nonionic substances remain concentrated on the surface of the permeable membrane, increasing pressure loss, but since they have passed through the polisher device 3 configured according to the present invention, Pressure losses are significantly reduced. In the secondary system of the ultrapure water production process, why is the pressure loss of the membrane separation device reduced when high-purity pure water that has passed through the polisher device configured according to the present invention is supplied to the membrane separation device? Although it is not clearly understood, when fine nonionic substances pass through the anion exchange resin layer, their properties change to make them difficult to adhere to the permeable membrane surface. This is thought to be due to a reduction in membrane contamination, and this phenomenon of decreased membrane contamination does not appear for any particular permeable membrane. The anion exchange resin employed in the anion exchange resin layer in the polisher device of the present invention may be either strongly basic, weakly basic, porous, or gel, but because of its high basicity, A porous type is preferable from the viewpoint of basicity and stain resistance. The liquid passing rate is approximately SV50 to 100hr -1 . The mixing ratio of the strongly basic anion exchange resin and the strongly acidic cation exchange resin in the mixed layer is the volume ratio of strongly basic anion exchange resin: strongly acidic cation exchange resin = 1:
A ratio of 1 to 2:1 is adopted. Furthermore, a gel type ion exchange resin is employed as the mixed layer. [Example] Next, the present invention will be explained with reference to Examples, but the present invention is not limited to the following Examples. Example 1 Tap water was mixed with strongly acidic cation exchange resin SK1B (manufactured by Mitsubishi Chemical Industries, Ltd., hereinafter simply referred to as SK1B).
After passing water sequentially through a cation exchange tower filled with a cation exchange tower filled with a strong basic anion exchange resin SA10A (manufactured by Mitsubishi Chemical Industries, Ltd., hereinafter simply referred to as SA10A), a reverse osmosis membrane SC- 3100 (manufactured by Toray Industries, Inc.) with an operating pressure of 25 kg/cm 2 ,
The water was treated with a recovery rate of 85%, and the water was further processed by passing through a mixed resin layer consisting of a mixed resin layer containing SK1B and SA10A at a ratio of 1:2 (volume ratio) to convert the effluent to high-purity water. . The regeneration level of mix bed policy is 100g for SK1B.
HCl/-resin, 100g for SA10A-
NaOH/-resin. The average quality of the high purity water was as shown in Table 1.
【表】
上述の高純度純水を第１図に示されるフローダ
イヤグラムの超純水製造工程二次系システムより
超純水の製造を行なつた。
高純度純水は一旦FRP製の高純度純水タンク
に貯蔵した後供給するようにした。
紫外線殺菌装置としてはGWO−1524P（東京芝
浦電気株式会社製）を使用し、波長254nｍ、照
射時間約40秒となるようにした。
紫外線殺菌装置に続く本発明のポリシヤー装置
としては、再生レベル300ｇ−HCl／−樹脂で
再生したSK1Bと500ｇ−NaOH／−樹脂で再
生したSA10AをSK1B：SA10A＝１：２（体積
比）の割合で混合してカートリツジ式のカラムに
充填し、さらにこの混合樹脂の上部に前記混合樹
脂と同量の強塩基性陰イオン交換樹脂PA312（三
菱化成工業株式会社製、以下PA312と記す。）を
充填積層させた。PA312の再生レベルは500ｇ−
NaOH／−樹脂とした。またSVは50hr-1とし
た。
膜分離装置としては限外過膜ACL−1010（旭
化成工業株式会社製）を装着し、入口圧力1.5
Kg／cm2、回収率90％で運転できるようにした。
上述のような二次系システムに高純度純水を通
液し超純水を製造し、その時の膜分離装置の圧力
の変化は第２図のようであつた。
また、超純水の平均水質は第２表のようであつ
た。[Table] The above-mentioned high-purity pure water was produced using the secondary system of the ultrapure water production process shown in the flow diagram shown in FIG. High-purity water was first stored in a high-purity water tank made of FRP and then supplied. GWO-1524P (manufactured by Tokyo Shibaura Electric Co., Ltd.) was used as the ultraviolet sterilizer, and the wavelength was 254 nm and the irradiation time was about 40 seconds. The polisher device of the present invention following the ultraviolet sterilization device has a regeneration level of SK1B regenerated with 300g-HCl/-resin and SA10A regenerated with 500g-NaOH/-resin at a ratio of SK1B:SA10A=1:2 (volume ratio). The mixed resin was mixed and packed into a cartridge-type column, and the same amount of strong basic anion exchange resin PA312 (manufactured by Mitsubishi Chemical Industries, Ltd., hereinafter referred to as PA312) as the mixed resin was packed on top of this mixed resin. Laminated. The playback level of PA312 is 500g-
NaOH/-resin. Moreover, SV was set to 50hr -1 . The membrane separation device is equipped with ultrafiltration membrane ACL-1010 (manufactured by Asahi Kasei Corporation), and the inlet pressure is 1.5.
Kg/cm 2 and the recovery rate was 90%. Highly purified water was passed through the secondary system as described above to produce ultrapure water, and the pressure change in the membrane separation device at that time was as shown in Figure 2. The average quality of the ultrapure water was as shown in Table 2.
本発明方法によれば超純水製造システムの二次
系システムにおける膜分離装置の透過膜の洗浄頻
度を減少できる。
According to the method of the present invention, the frequency of cleaning the permeable membrane of the membrane separation device in the secondary system of the ultrapure water production system can be reduced.
第１図は超純水製造システムの二次系システム
のフローダイヤグラムを示す図である。
図中１は高純度純水タンク、２は紫外線殺菌装
置、３はポリシヤー装置、４は膜分離装置、５は
超純水供給導管、６は超純水戻り導管を示す。
第２図は実施例１と比較例１に於ける膜分離装
置の圧力の変化を示したものであり、縦軸は圧力
（Kg／cm2）を横軸は通水日数（日）を示す。第３
図は強塩基性陰イオン交換樹脂と強酸性陽イオン
交換樹脂の混合層の上部に積層させる強塩基性陰
イオン交換樹脂の量を変化させた時の運転開始か
ら30日後の膜分離装置の圧力の変化を示す。縦軸
は圧力（Kg／cm2）を横軸はPA312のSV（１／Hr）
を示す。
FIG. 1 is a diagram showing a flow diagram of a secondary system of an ultrapure water production system. In the figure, 1 is a high purity water tank, 2 is an ultraviolet sterilizer, 3 is a polisher device, 4 is a membrane separation device, 5 is an ultrapure water supply conduit, and 6 is an ultrapure water return conduit. Figure 2 shows the change in pressure of the membrane separation device in Example 1 and Comparative Example 1, where the vertical axis shows the pressure (Kg/cm 2 ) and the horizontal axis shows the number of days of water flow (days). . Third
The figure shows the pressure of the membrane separation device 30 days after the start of operation when the amount of strongly basic anion exchange resin layered on top of the mixed layer of strongly basic anion exchange resin and strongly acidic cation exchange resin was varied. shows the change in The vertical axis is pressure (Kg/cm 2 ) and the horizontal axis is PA312 SV (1/Hr).
shows.
Claims (1)
を、殺菌装置、ポリシヤー装置、透過膜を内蔵す
る膜分離装置の順に通過処理して超純水として供
給するように構成された超純水製造二次系システ
ムに於て、ポリシヤー装置として陰イオン交換樹
脂層及び強塩基性陰イオン交換樹脂と強酸性陽イ
オン交換樹脂の混合層からなるポリシヤー装置を
使用することを特徴とする透過膜の汚染防止方
法。1 Ultrapure water configured to pass high-purity water from the primary ultrapure water production system through a sterilizer, a polisher, and a membrane separation device with a built-in permeable membrane in that order and supply it as ultrapure water. A permeable membrane characterized in that a polisher device comprising an anion exchange resin layer and a mixed layer of a strongly basic anion exchange resin and a strongly acidic cation exchange resin is used as a polisher device in a secondary manufacturing system. Pollution prevention methods.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9619385A JPS61254293A (en) | 1985-05-07 | 1985-05-07 | Method for preventing contamination of permeable membrane |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9619385A JPS61254293A (en) | 1985-05-07 | 1985-05-07 | Method for preventing contamination of permeable membrane |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS61254293A JPS61254293A (en) | 1986-11-12 |
| JPH0142754B2 true JPH0142754B2 (en) | 1989-09-14 |
Family
ID=14158466
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP9619385A Granted JPS61254293A (en) | 1985-05-07 | 1985-05-07 | Method for preventing contamination of permeable membrane |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS61254293A (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0664323B2 (en) * | 1987-01-30 | 1994-08-22 | 富士写真フイルム株式会社 | Cleaning method for automatic developing equipment |
| JPH02198687A (en) * | 1989-01-26 | 1990-08-07 | Asahi Chem Ind Co Ltd | Production of pure water |
| WO2013106657A1 (en) * | 2012-01-12 | 2013-07-18 | Scarpa Philip J | A water filtration device for the production of medical grade water for injection |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS4929422A (en) * | 1972-07-18 | 1974-03-15 |
-
1985
- 1985-05-07 JP JP9619385A patent/JPS61254293A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS61254293A (en) | 1986-11-12 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |