JP2773231B2 - Leak test method for hydrophobic hollow fiber type porous membrane - Google Patents
Leak test method for hydrophobic hollow fiber type porous membraneInfo
- Publication number
- JP2773231B2 JP2773231B2 JP10674489A JP10674489A JP2773231B2 JP 2773231 B2 JP2773231 B2 JP 2773231B2 JP 10674489 A JP10674489 A JP 10674489A JP 10674489 A JP10674489 A JP 10674489A JP 2773231 B2 JP2773231 B2 JP 2773231B2
- Authority
- JP
- Japan
- Prior art keywords
- membrane
- leak test
- hollow fiber
- film
- fiber type
- 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 - Fee Related
Links
Description
【発明の詳細な説明】 （産業上の利用分野） 本発明は、疎水性の中空糸型多孔質膜の親水化処理と
リークテストを同時に行ない得る簡便な方法に関するも
のである。Description: TECHNICAL FIELD The present invention relates to a simple method for simultaneously performing a hydrophilic treatment and a leak test on a hydrophobic hollow fiber type porous membrane.
（従来の技術） 中空糸型多孔質膜は、比較的コンパクトなモジュール
で大きな膜面積を得ることができ、水の浄化用膜（医療
用のパイロジェンフリー純水、電子材料製造用超純水等
の製造用膜）、結漿分離膜バイオリアクター（発酵にお
ける生産物の分離、生体触媒の循環利用もしくは固定化
用担体）など広い分野への応用が注目されている。これ
ら用途のほとんどは、水を溶媒として用いる水溶液系で
あり、膜が疎水性で親水化されていない場合には、膜細
孔が濡れず、水の透過速度が非常に低くなり膜性能がで
ない。しかしながら、親水性の膜素材は、膜強度、耐久
性、微生物による分解など、様々な問題点を有し、広く
一般的な用途には使用が難しい。従って、疎水性膜の親
水化は重要な課題であり、種々の方法が考案されてい
る。(Prior art) A hollow fiber type porous membrane can obtain a large membrane area with a relatively compact module, and can be used as a water purification membrane (pyrogen-free pure water for medical use, ultrapure water for electronic material production, etc.). Application to a wide range of fields has attracted attention, such as a membrane for the production of biomass, and a plasma separation membrane bioreactor (separation of products in fermentation, recycling of biocatalysts or carriers for immobilization). Most of these uses are aqueous systems using water as a solvent, and when the membrane is hydrophobic and not hydrophilized, the pores of the membrane do not wet and the permeation rate of water is very low, resulting in poor membrane performance . However, hydrophilic membrane materials have various problems, such as membrane strength, durability, and decomposition by microorganisms, and are difficult to use for general applications. Therefore, hydrophilization of a hydrophobic membrane is an important subject, and various methods have been devised.
疎水性膜の親水化手段としては、界面活性剤や低表面
張力で水と混和性のある溶媒を疎水性膜と接触させ、水
の表面張力を下げた状態で膜細孔内に水を充填し、膜の
濡れ性を付与する方法、疎水性の膜素材に親水性基を反
応により結合させ、膜を親水化する方法また、疎水性膜
素材を分解して親水性基を作り、親水化する方法などが
考案されている。しかし、界面活性剤もしくは低表面張
力の溶媒を用いる第一の方法以外は、複雑な工程を含み
コスト的に高くつくこと、特に医療用途の膜において
は、安全性の面から未反応物や、反応生成物等の残留、
溶出が大きな問題となる。従って、医学的に安全な界面
活性剤、もしくは低表面張力の水混和性溶媒による第一
の方法が最も望ましい。As a means for hydrophilizing the hydrophobic membrane, a surfactant or a solvent that is miscible with water at low surface tension is brought into contact with the hydrophobic membrane, and water is filled into the pores of the membrane with the surface tension of water reduced. A method of imparting wettability to a film, a method of bonding a hydrophilic group to a hydrophobic film material by a reaction to make the film hydrophilic, and a method of decomposing a hydrophobic film material to form a hydrophilic group to make the film hydrophilic. A method for doing so has been devised. However, except for the first method using a surfactant or a solvent having a low surface tension, it is expensive in terms of cost including complicated steps, particularly in a medical use film, and in terms of safety, unreacted substances and Residual reaction products, etc.
Elution is a major problem. Therefore, the first method with a medically safe surfactant or a low surface tension water-miscible solvent is most desirable.
膜モジュールのリークテストは、膜を使用する上で不
可欠なプロセスであり、膜使用時には必ず実施されるも
のである。しかしながらこのプロセスにおいて、膜の親
水化剤（界面活性剤もしくは低表面張力の水混和性溶
媒）がリークテスト用の液体によって除去され、膜の親
水性が失なわれてしまうことがある。すなわちリークテ
スト用液体が親水化剤と混和性を持つ場合には、リーク
テストを行なう際に、膜に付着させておいた親水化処理
剤が、リークテスト用液体に溶解混和し、この排出と伴
に除去されてしまう。また揮発性の親水化処理剤の場合
もリークテスト後、リークテスト用液体を気化して除去
するような場合には、蒸散してその親水化能を失なって
しまうことになる。しかしながら膜モジュールのリーク
テストは膜使用の上で不可欠なプロセスであり、これを
なくしてしまうことはできない。膜の欠陥やピンホー
ル、破損等を検出するための手段としてのリークテスト
は、バブルポイント測定と同等の原理に基いて測定され
る。すなわち、膜細孔部に、リークテスト用液体を充填
し、これが気体の圧力によって排除される圧力をバブル
ポイントと呼んでいるが、膜に欠陥、ピンホール、破損
等が存在する場合においては、このバブルポイント以下
の圧力で、欠陥部より液体が排除され、圧力低下が発生
し、これにより膜欠陥の有無が検出される。この時、リ
ークテストに用いられる液体は、疎水性多孔質膜に濡れ
性をもつ必要がある。すなわち、膜に存在するあらゆる
細孔中に、このリークテスト用の液体が充填されなけれ
ば、液体による閉塞のない細孔より、気体が抜け出し、
圧力低下が発生するため、膜欠陥を検出することができ
ない。またこれら液体は膜使用に際して問題とならない
よう、蒸発水洗等により容易に除去され、特に医療用膜
の分野において、安全性に問題があってはならない。The leak test of the membrane module is an indispensable process for using the membrane, and is always performed when the membrane is used. However, in this process, the hydrophilizing agent (surfactant or water-miscible solvent having a low surface tension) of the membrane may be removed by the liquid for the leak test, and the hydrophilicity of the membrane may be lost. That is, when the leak test liquid is miscible with the hydrophilizing agent, the hydrophilizing treatment agent attached to the film dissolves and mixes with the leak test liquid during the leak test, and Will be removed along with it. Also, in the case of a volatile hydrophilizing agent, if the liquid for the leak test is vaporized and removed after the leak test, the liquid is evaporated and loses its hydrophilizing ability. However, the leak test of the membrane module is an indispensable process in using the membrane, and cannot be eliminated. A leak test as a means for detecting a defect, a pinhole, breakage, or the like of a film is measured based on the same principle as the bubble point measurement. That is, the pores of the membrane are filled with a leak test liquid, and the pressure that is removed by the pressure of the gas is called a bubble point.If the membrane has defects, pinholes, breakage, etc., At a pressure below this bubble point, the liquid is removed from the defective portion and a pressure drop occurs, thereby detecting the presence or absence of a film defect. At this time, the liquid used for the leak test needs to have wettability to the hydrophobic porous membrane. That is, if all the pores present in the membrane are not filled with the liquid for the leak test, the gas escapes from the pores not clogged by the liquid,
Since a pressure drop occurs, a film defect cannot be detected. In addition, these liquids are easily removed by washing with evaporating water or the like so as not to cause a problem when the membrane is used, and there should be no problem in safety particularly in the field of medical membranes.
（発明が解決しようとする課題） 本発明は前記従来技術の問題点即ち、リークテスト中
に溶解除去されることがなく、中空糸膜の細孔部までリ
ークテスト用液体が充填され正確なリークテストを可能
にする方法の提供である。(Problems to be Solved by the Invention) The present invention has a problem of the prior art, that is, the leak test liquid is filled up to the pores of the hollow fiber membrane without being dissolved and removed during the leak test, and an accurate leak is obtained. Providing a way to enable testing.
（課題を解決するための手段） 前記問題点を解決するため鋭意検討の結果本発明に到
達した。すなわち、本発明は膜の平均細孔径が0.01μｍ
以上である疎水性の中空糸型多孔質膜において、膜細孔
部に、膜素材に濡れ性をもつリークテスト用液体を充填
し、中空糸膜内部あるいは外部より圧力をかけて、膜の
欠陥、ピンホール、破損を調らべるリークテスト法にお
いて、該リークテスト用液体に親水化処理に用いること
のできる高沸点溶媒を0.1〜10wt％溶解した液体を用い
ることを特徴とする疎水性の中空糸型多孔質膜の親水化
処理を兼ねたリークテスト法である。(Means for Solving the Problems) As a result of intensive studies to solve the above problems, the present invention has been reached. That is, in the present invention, the average pore diameter of the membrane is 0.01 μm
In the hydrophobic hollow fiber type porous membrane described above, the pores of the membrane are filled with a leak test liquid having wettability to the membrane material, and pressure is applied from inside or outside of the hollow fiber membrane to cause a defect in the membrane. In a leak test method for examining pinholes and breakage, a liquid obtained by dissolving 0.1 to 10% by weight of a high boiling point solvent usable for hydrophilization treatment in the liquid for leak test is used. This is a leak test method that also serves as a hydrophilic treatment for a hollow fiber type porous membrane.
リークテスト用液体としては、エチルアルコールやグ
リセリンのようなアルコール類、ハロゲン化炭化水素
類、ケント類等があるが、膜を溶解するようなものは用
いることができないため、膜素材に合わせて選択する必
要がある。Liquids for leak test include alcohols such as ethyl alcohol and glycerin, halogenated hydrocarbons, Kents, etc., but those that dissolve the film cannot be used, so select according to the film material. There is a need to.
また、膜の細孔保持剤として、不揮発性の親水化処理
剤を比較的多量に膜に含浸させる方法が従来の一般的な
親水化膜であった。しかし本研究者らが検討した結果に
おいて、精密濾過膜の細孔径領域（0.01〜数μ）では、
水の蒸発による表面張力の作用はほとんど受けず、不揮
発性の親水化処理剤を細孔に充填しておく必要がなく、
親水化処理剤は、使用前細孔壁等の表面に極少量あれば
よいことが判明した。このことは、モジュール接着にお
ける孔保持剤が必要でなく、これにより、モジュールの
接着剤と孔保持剤の副次反応がなく、モジュール化後の
溶出物の発生が抑えられるといったメリットも有してい
る。このようにして、膜の親水化処理とリークテストを
一つのプロセスにおいて行なうことは、工程の削減のみ
ならず、接着時の副次反応物の抑制、親水化処理前の使
用量を大幅に減らすことといった大きなメリットを有す
るものである。In addition, a conventional method of impregnating a membrane with a relatively large amount of a non-volatile hydrophilizing agent as a pore retaining agent for the membrane has been a conventional general hydrophilized membrane. However, as a result of the investigations by the present researchers, in the pore diameter region (0.01 to several μ) of the microfiltration membrane,
There is almost no effect of surface tension due to the evaporation of water, and there is no need to fill the pores with a non-volatile hydrophilizing agent,
It has been found that the hydrophilizing agent only needs to be contained in an extremely small amount on the surface such as the pore wall before use. This has the advantage that a pore-holding agent is not required for module bonding, and thus there is no side reaction between the module adhesive and the hole-holding agent, and the generation of eluate after modularization is suppressed. I have. In this manner, performing the hydrophilic treatment and the leak test of the film in one process not only reduces the number of steps but also suppresses by-products during bonding and greatly reduces the amount used before the hydrophilic treatment. It has a great merit of that.
（発明の具体的内容） 一般に、膜のリークテストは、膜をモジュールに組み
立てた後、すなわち、使用可能な状態において実施され
る。しかし膜の親水化処理は製膜工程から膜使用の直前
までのどの工程であっても問題はなく、使用時に親水化
状態であればよく、リークテストの段階でも全く問題は
ない。本発明の方法は疎水性の中空糸型多孔質膜がモジ
ュール化された後に実施される。モジュールの形態とし
ては、直線状両端口型、直線状片側開口型、Ｖ字型片側
開口型などどのような形態であってもよい。この中空糸
モジュール容器に親水化処理両性溶媒を含むリークテス
ト用液体を充填し、十分に中空糸膜に含浸させる。次に
モジュールの中空糸開口端に気体でバブルポイント以下
の圧力を加える。このようにして膜のリークテストを行
ない、テスト後モジュールより、リークテスト用液体を
抜き取って、膜を通風乾燥等で乾燥もしくはそのまま放
置する。この時、親水処理剤が膜面に均一に残留し、親
水化処理された状態となる。以下、具体的は事例により
説明する。(Specific Content of the Invention) Generally, a leak test of a membrane is performed after the membrane is assembled into a module, that is, in a usable state. However, there is no problem in any step of the hydrophilic treatment of the film from the film forming step to immediately before the use of the film, as long as it is in a hydrophilic state at the time of use, and there is no problem at the stage of the leak test. The method of the present invention is performed after the hydrophobic hollow fiber type porous membrane is modularized. As the form of the module, any form such as a linear double-sided opening type, a linear single-sided opening type, a V-shaped single-sided opening type may be used. This hollow fiber module container is filled with a leak test liquid containing a hydrophilizing amphoteric solvent, and sufficiently impregnated in the hollow fiber membrane. Next, pressure below the bubble point is applied to the open end of the hollow fiber of the module with gas. In this way, the film is subjected to a leak test. After the test, a liquid for leak test is extracted from the module, and the film is dried by ventilation drying or left as it is. At this time, the hydrophilic treatment agent remains uniformly on the film surface, and becomes in a state of being subjected to the hydrophilic treatment. Hereinafter, a specific example will be described.
（実施例） 疎水性中空糸型多孔質膜としてセルローストリアセテ
ート製、平均孔径0.1μｍの中空糸膜を用いて、直線状
両端開口型モジュールをウレタン樹脂を接着剤として作
製した。リークテスト用液体としてはエタノールを用
い、親水化処理剤としてはグリセリンを使用した。(Example) Using a hollow fiber membrane made of cellulose triacetate and having an average pore diameter of 0.1 µm as a hydrophobic hollow fiber type porous membrane, a linear open-ended module was produced using a urethane resin as an adhesive. Ethanol was used as the liquid for the leak test, and glycerin was used as the hydrophilizing agent.
グリセリン重量％が1,5,10wt％の３種のエタノールグ
リセリン混合液を用いてリークテストを実施したのち通
風乾燥後、水の透過速度および、溶出物としてウレタン
オリゴマー（Vo）量を調査した。比較例として、エタノ
ールのみでリークテストを行なったもの（比較例１）。
無処理のもの（比較例２）。A leak test was performed using three types of ethanol glycerin mixed solutions having glycerin weight percentages of 1, 5, and 10 wt%, and thereafter, after ventilation drying, the water permeation rate and the amount of urethane oligomer (Vo) as an eluate were investigated. As a comparative example, a leak test was performed using only ethanol (Comparative Example 1).
No treatment (Comparative Example 2).
また、あらかじめグリセリンを中空糸に付着させたの
ち、モジュールを作成した場合（比較例３）の３種類を
比較例として同様の調査を行なった。In addition, the same investigation was carried out using three types of comparative examples, in which glycerin was previously attached to the hollow fibers and then a module was prepared (Comparative Example 3).
第１表のように、エタノールグリセリン混合液でリー
クテストを行なった３種のモジュールでは、水の透過速
度、水ぬれ性に変わりがなく、また中空糸にあらかじめ
グリセリンを付着させてモジュール化したものにおいて
も、同等の水透過性能、水ぬれ性を有している。しかし
親水化処理剤を付着していないものでは水の透過速度、
水ぬれ性とも劣っていた。 As shown in Table 1, the three types of modules that were subjected to a leak test with an ethanol-glycerin mixed solution did not change in water permeation rate and water wettability, and were made by attaching glycerin to hollow fibers in advance to form a module. Also have the same water permeation performance and water wettability. However, in the case where no hydrophilic treatment agent is attached, the water permeation speed,
Poor water wettability.
また、比較例３のグリセリン付着中空糸モジュールで
はウレタンオリゴマー（Vo）の発生が認められた。In the glycerin-attached hollow fiber module of Comparative Example 3, generation of urethane oligomer (Vo) was observed.
（発明の効果） 本発明による親水化処理を兼ねた中空糸膜モジュール
のリークテスト法は、親水化処理とリークテストを一度
に行ない得る簡便な方法であり、接着時の副次反応物の
発生がなく、親水化処理剤の使用量を減らすといったメ
リットを有するものである。(Effects of the Invention) The leak test method for a hollow fiber membrane module that also serves as a hydrophilizing treatment according to the present invention is a simple method that can perform the hydrophilizing treatment and the leak test at one time, and the generation of by-products during adhesion. This has the advantage of reducing the amount of the hydrophilizing agent used.
───────────────────────────────────────────────────── フロントページの続き (56)参考文献 特開 平２−11155（ＪＰ，Ａ) 特開 昭63−249569（ＪＰ，Ａ) 特開 平１−119310（ＪＰ，Ａ) 特開 昭58−129230（ＪＰ，Ａ) 特公 昭63−15858（ＪＰ，Ｂ２) 特公 平３−2418（ＪＰ，Ｂ２) (58)調査した分野(Int.Cl.6，ＤＢ名) G01M 3/02 G01M 3/04 G01N 15/08 B01D 69/68 D01F 6/00 A61M 1/18────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-2-11155 (JP, A) JP-A-63-249569 (JP, A) JP-A-1-119310 (JP, A) JP-A-58-1983 129230 (JP, A) JP 63-15858 (JP, B2) JP 3-2418 (JP, B2) (58) Fields investigated (Int. Cl. 6 , DB name) G01M 3/02 G01M 3 / 04 G01N 15/08 B01D 69/68 D01F 6/00 A61M 1/18
Claims (1)
性の中空糸型多孔質膜において、膜細孔部に、膜素材に
濡れ性をもつリークテスト用液体を充填し、中空糸膜内
部あるいは外部より圧力をかけて、膜の欠陥、ピンホー
ル、破損を調らべるリークテスト法において、該リーク
テスト用液体に親水化処理に用いることのできる高沸点
溶媒を0.1〜10wt％溶解した液体を用いることを特徴と
する疎水性の中空糸型多孔質膜の親水化処理を兼ねたリ
ークテスト法。1. A hydrophobic hollow fiber type porous membrane having an average pore diameter of 0.01 μm or more in a membrane, wherein the pores of the membrane are filled with a leak test liquid having wettability to the membrane material. In a leak test method for examining defects, pinholes and breakage of the film by applying pressure from the inside or outside of the film, a high boiling point solvent that can be used for hydrophilization treatment is added to the leak test liquid in an amount of 0.1 to 10% by weight. A leak test method which also serves to hydrophilize a hydrophobic hollow fiber type porous membrane, characterized by using a dissolved liquid.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10674489A JP2773231B2 (en) | 1989-04-25 | 1989-04-25 | Leak test method for hydrophobic hollow fiber type porous membrane |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10674489A JP2773231B2 (en) | 1989-04-25 | 1989-04-25 | Leak test method for hydrophobic hollow fiber type porous membrane |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH02284035A JPH02284035A (en) | 1990-11-21 |
| JP2773231B2 true JP2773231B2 (en) | 1998-07-09 |
Family
ID=14441432
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP10674489A Expired - Fee Related JP2773231B2 (en) | 1989-04-25 | 1989-04-25 | Leak test method for hydrophobic hollow fiber type porous membrane |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2773231B2 (en) |
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| TW362041B (en) * | 1996-12-27 | 1999-06-21 | Asahi Chemical Ind | Leakage inspection apparatus and method for filter film |
| JP4538732B2 (en) * | 2005-02-28 | 2010-09-08 | 東洋紡績株式会社 | Hollow fiber membrane module leak detection method and leak detection device |
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| WO2010142673A1 (en) | 2009-06-11 | 2010-12-16 | Siemens Water Technologies Corp. | Methods for cleaning a porous polymeric membrane and a kit for cleaning a porous polymeric membrane |
| WO2011136888A1 (en) | 2010-04-30 | 2011-11-03 | Siemens Industry, Inc | Fluid flow distribution device |
| CN103118766B (en) | 2010-09-24 | 2016-04-13 | 伊沃夸水处理技术有限责任公司 | The fluid of membrane filtration system controls manifold |
| HUE058060T2 (en) | 2011-09-30 | 2022-07-28 | Rohm & Haas Electronic Mat | Isolation valve |
| JP2014528352A (en) | 2011-09-30 | 2014-10-27 | エヴォクア ウォーター テクノロジーズ エルエルシーＥｖｏｑｕａ Ｗａｔｅｒ Ｔｅｃｈｎｏｌｏｇｉｅｓｌｌｃ | Improved manifold structure |
| JP2013108774A (en) * | 2011-11-17 | 2013-06-06 | Toppan Printing Co Ltd | Pressure inspection device |
| KR101743423B1 (en) * | 2012-03-26 | 2017-06-05 | 미쯔비시 케미컬 주식회사 | Porous film preservation solution |
| AU2013280452B2 (en) | 2012-06-28 | 2017-07-20 | Evoqua Water Technologies Llc | A potting method |
| US9868834B2 (en) | 2012-09-14 | 2018-01-16 | Evoqua Water Technologies Llc | Polymer blend for membranes |
| US9962865B2 (en) | 2012-09-26 | 2018-05-08 | Evoqua Water Technologies Llc | Membrane potting methods |
| WO2014052071A1 (en) | 2012-09-26 | 2014-04-03 | Evoqua Water Technologies Llc | Membrane securement device |
| EP2900356A1 (en) | 2012-09-27 | 2015-08-05 | Evoqua Water Technologies LLC | Gas scouring apparatus for immersed membranes |
| EP3052221B1 (en) | 2013-10-02 | 2022-12-14 | Rohm & Haas Electronic Materials Singapore Pte. Ltd | Device for repairing a membrane filtration module |
| WO2017011068A1 (en) | 2015-07-14 | 2017-01-19 | Evoqua Water Technologies Llc | Aeration device for filtration system |
-
1989
- 1989-04-25 JP JP10674489A patent/JP2773231B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH02284035A (en) | 1990-11-21 |
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