JP2001079366A - Method for washing membrane - Google Patents

Method for washing membrane

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Publication number
JP2001079366A
JP2001079366A JP25777499A JP25777499A JP2001079366A JP 2001079366 A JP2001079366 A JP 2001079366A JP 25777499 A JP25777499 A JP 25777499A JP 25777499 A JP25777499 A JP 25777499A JP 2001079366 A JP2001079366 A JP 2001079366A
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Japan
Prior art keywords
membrane
water
membrane module
backwashing
raw water
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Pending
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JP25777499A
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Japanese (ja)
Inventor
Yoshihiko Mori
Takehiko Ootoyo
武彦 大豊
吉彦 森
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Asahi Kasei Corp
旭化成株式会社
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Priority to JP25777499A priority Critical patent/JP2001079366A/en
Publication of JP2001079366A publication Critical patent/JP2001079366A/en
Application status is Pending legal-status Critical

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Abstract

PROBLEM TO BE SOLVED: To surely prevent the damage of a membrane and to maintain high membrane filtration flow rate over a long period of time by backwashing the membrane while rocking the membrane by introducing gas to the raw water side of the membrane and similarly forcibly feeding the liquid containing sodium hypochlorite and the like or gas from the filtered liquid side.
SOLUTION: The raw water 1 consisting of river surface running water, etc., is fed forcibly to a membrane module 4 by a raw water feed pump 3 from a circulation tank 2, and the filtered water obtained here is stored at a filtered water tank 5. At the time of backwashing of the membrane module 4, the filtered water in the filtered water tank 5 is fed forcibly to the membrane module 4 by a backwashing pump 6. At this time, the sodium hypochlorite aquatic solution stored in an oxidizing agent tank 8 is poured into the filtered water side of the membrane module 4 by an oxidizing agent feed pump 9. The air generated at a compressor 7 is fed simultaneously to the raw water side of the membrane module 4 to air-bubble the membrane module 4. In such a way, an adhered matter at the membrane module 4 is surely decomposed oxidatively and also peeled.
COPYRIGHT: (C)2001,JPO

Description

【発明の詳細な説明】 DETAILED DESCRIPTION OF THE INVENTION

【0001】 [0001]

【発明の属する技術分野】本発明は、上水道や工業用水、あるいは下水二次処理水の濾過処理、および下水、 The present invention relates to the water supply or industrial water or filtered sewage treatment secondary treatment water, and sewage,
排水の濾過処理に用いられる膜の洗浄方法に関するものであり、膜の損傷を起こさず高い洗浄回復性が得られる結果、高い濾過流束が維持できるというものである。 Relates to a method for cleaning membranes used in the filtration of waste water, as a result of high cleaning recovery without causing damage to the film can be obtained, it is that higher filtration flux can be maintained.

【0002】 [0002]

【従来の技術】種々の原水の濾過に用いられる濾過膜は、濾過精度に優れる為、各種の濾過装置に用いられている。 BACKGROUND OF THE INVENTION Various filtration membranes used in the filtration of the raw water is excellent in filtration accuracy, it is used in a variety of filtration apparatus. しかし、濾過の継続に伴い原水中の有機物等の除去対象物質が膜面に付着し、表面の孔を閉塞するため徐々に濾過性能が低下し、ついには濾過できなくなってしまう。 However, removal target substances such as organic substances in the raw water with the continuation of the filtration adheres to the film surface, and decreases gradually filtering performance to occlude the pores of the surface, finally it becomes impossible filtered. そこで、濾過性能を維持するための膜の洗浄方法として膜の濾過方向とは逆方向から濾水あるいは清澄水を噴出させて膜の濾過面の付着物を除去する逆流洗浄が用いられている。 Therefore, backflow washing by ejecting a drainage or clarified water from the opposite direction to remove the filtering surface of the deposit of film is used the filtration direction of the film as a method for cleaning membranes to maintain filtration performance. あるいは、よりその効果を高めるため逆流洗浄水に次亜塩素酸ソーダを添加したり、特開平4 Alternatively, or addition of sodium hypochlorite in the backwash water order to enhance the effect, JP-4
−310220号公報に示されているように、オゾン水を用いて逆流洗浄する方法や特開昭60−58222号公報に開示されているオゾン化加圧空気で逆洗する方法が知られている。 As shown in -310220 discloses a method of backwashing with ozonated pressurized air as disclosed in the method and Sho 60-58222 discloses that backwashing with ozone water are known . さらには特開昭63−42703号公報に開示されているように、オゾン化空気を中空糸膜の原水側に気泡として注入する方法が知られている。 Furthermore, as disclosed in JP-A-63-42703, a method of injecting the bubble ozonized air to the raw water side of the hollow fiber membranes are known.

【0003】 [0003]

【発明が解決しようとする課題】しかし、従来の逆流洗浄のみによる洗浄方法では、逆流洗浄水は、孔の閉塞が軽微な、即ち水力学的抵抗が少ない部分に優先的に流れるため、閉塞が軽微な部分は洗浄されるが、完全に閉塞した孔にはほとんど逆洗水が流れないため洗浄されない。 [SUMMARY OF THE INVENTION However, in the cleaning method using only conventional backwashing, backwash water is blockage of pores minor, that is, the hydraulic resistance to flow in preferentially small portions, blockage While minor part is cleaned, not completely occluded pores washed for little backwash water flows. 従って膜面全体が洗浄できず、逆流洗浄後も十分に濾過性能が回復しないという問題があった。 Thus the whole film surface can not be cleaned sufficiently filtering performance even after backwashing there is a problem that does not recover. 又、膜表面の付着物質が多い場合は、逆流洗浄時の圧力だけでは厚い付着層を剥離できず、洗浄回復性が不十分であった。 Further, if the deposited material is often of the film surface can not be peeled off a thick adhesion layer only pressure during back washing, the washing recovery was insufficient.

【0004】一方、原水側に気泡を導入する方法は、特に導入された気泡により膜が揺動し、膜同士が触れ合うことにより膜表面の付着物質が掻き落とされることにより洗浄が行われるため、その効果は逆流洗浄よりも大きい。 On the other hand, for a method for introducing bubbles into the raw water side, the film is swung by the bubble that is specifically introduced, is washed by the deposited material of the membrane surface is scraped off by the touch membrane together takes place, the effect is greater than the backwashing. しかし、逆に膜同士のこすれによってむしろ付着物質が孔内に押し込まれ、かえって孔の閉塞が生じたり、 However, rather adhered substances by rubbing between the films conversely pushed into the hole, rather blockage or caused holes,
あるいは膜表面がこすられる結果、孔が押しつぶされてしまい、かえって濾過性能が低下するという問題があった。 Or a result of the film surface is rubbed, it would be crushed a hole, rather filtration performance is lowered. 即ち、膜を傷つけずに効果的に洗浄を行い、高い濾過流束を維持する方法は未だ見いだされていない。 That performs effectively cleaned without damaging the film, how to maintain a high filtration flux has not yet been found.

【0005】 [0005]

【課題を解決するための手段】本発明者らは、膜の洗浄方法について鋭意検討した結果、以下の発明を完成するに至った。 The present inventors have SUMMARY OF THE INVENTION are a result of extensive studies for a method for cleaning membranes, and have completed the following invention. すなわち本発明は、多孔膜の洗浄方法において、原水側に気体を導入して膜を揺動させると同時に、 That is, the present invention provides a method of cleaning a porous membrane, when swinging the film by introducing a gas into the raw water side simultaneously,
濾液側から、加圧した次亜塩素酸ナトリウム、二酸化塩素、過酸化水素の少なくとも1以上を含む液体または気体で逆流洗浄することを特徴とする膜を洗浄する方法である。 From the filtrate side, a method of cleaning pressurized sodium hypochlorite, chlorine dioxide, a film characterized by backwashing with liquid or gas containing at least one or more of hydrogen peroxide.

【0006】以下に本発明の詳細を述べる。 [0006] described in detail of the present invention will be described below. 本発明の対象となる原水は、河川水、湖沼水、地下水、貯水、下水二次処理水、工場排水、下水などである。 Subject to raw water of the present invention, river water, lake water, ground water, water, sewage secondary treatment water, industrial effluent, sewage or the like. 従来、上記の様な原水を膜で濾過すると、該原水中に含まれる、使用する膜の孔径以上の大きさの懸濁物質や有機物は膜で阻止され、いわゆる濃度分極やケーク層を形成すると同時に、該原水中の有機物は膜を目詰まりさせたり、あるいは膜内部の網状組織に吸着する。 Conventionally, when filtering the raw water, such as described above in film, contained in the raw water, suspended solids and organic matter in the size of the hole diameter or the membrane used is blocked with a membrane, to form a so-called concentration polarization or cake layer At the same time, organic matter raw water is adsorbed or clog the membrane, or the membrane inside the network. その結果、原水を濾過した際の膜の濾過流束は、清澄水を濾過した際のそれに比べて数分の1から数十分の1にまで低下してしまい又、濾過の継続に従って濾過流束は徐々に低下していく。 As a result, the filtration flux of the membrane at the time of filtering the raw water, also will be reduced from a fraction of than that at the time of filtering the clarified water to several tenths, filtered flow according continuation of filtration the bundle is gradually reduced.

【0007】これらの膜を閉塞する物質は、一般に無機物粒子の周りを有機物が覆った状態で原水中に存在し、 [0007] substances for closing these membranes generally around the inorganic particles present in the raw water in a state in which organic material is covered,
表面の有機物による付着力で膜表面に強固に付着する。 Firmly attached to the membrane surface adhesion by organic matter on the surface.
このため通常行われる膜濾水や清澄水を用いた水圧を利用した逆流洗浄では、強固に付着した物を剥離できず、 Therefore, in the backwashing using a water pressure using an ordinary film drainage and refining the water takes place, it can not be peeled off those which strongly attached,
その洗浄回復効果は小さい。 The cleaning recovery effect is small. これに対し、次亜塩素酸ナトリウム、二酸化塩素、過酸化水素の少なくとも1以上を含む液体または気体で逆流洗浄を行うと、その酸化力により、膜に付着した物質表面の有機物が酸化分解あるいは変性され、膜表面から剥離し易くなる。 In contrast, sodium hypochlorite, when chlorine dioxide, backwashing with liquid or gas containing at least one or more of hydrogen peroxide, by its oxidizing power, organic matter oxidative decomposition or denaturation of the attached material surface layer It is, easily peeled off from the film surface. しかし、これら液体、気体の逆流洗浄のみでは、前述したように、 However, these liquids, the only back washing gas, as described above,
閉塞が軽微な部分は十分に洗浄されるが、完全に閉塞したり、あるいは付着層が厚い部分は、やはり十分な洗浄が行えない。 Although obstruction minor portion is sufficiently cleaned, completely closed or or deposited layer is thick portions, may not be performed again sufficient cleaning.

【0008】そこで、原水側に気体を導入し膜を揺動させると同時に、次亜塩素酸ナトリウム、二酸化塩素、過酸化水素の少なくとも1以上を含む液体または気体による逆流洗浄することにより、より効果的に付着物質を剥離することができる。 [0008] Thus, by introducing a gas into the raw water side simultaneously with the oscillating membrane, sodium hypochlorite, chlorine dioxide, by backwashing by liquid or gas containing at least one or more of hydrogen peroxide, more effective it can be separated adhere substance. また、通常原水側に気泡を導入して洗浄を行うと、膜同士が擦れ合い洗浄効果は高いものの、同時に膜表面に傷が付き、かえって透過流束が低下する場合がある。 Also, when normal cleaned by introducing air bubbles into the raw water side, although high cleaning effect film between rubbing, scratched at the same time the membrane surface, rather flux may decrease. しかし、本発明のように、逆流洗浄と同時に気体を導入すると、逆洗による水流または気流により膜同士の距離が離れ、過度にこすり合わされるのを防ぐ。 However, as in the present invention, when simultaneously introducing gas and backwashing, the distance between the films by water flow or air flow due to backwash leaves, avoid being rubbed excessively. 同時に、通常、膜と膜の間に詰まり易い、膜表面から脱落した付着物質も排出されやすくなる。 At the same time, usually easily clogged between the membrane and the membrane, also easily discharged deposited material off from the membrane surface.

【0009】以上のように、次亜塩素酸ナトリウム、二酸化塩素、過酸化水素の少なくとも1以上を含む液体または気体による逆流洗浄と同時に、原水側に気体を導入することにより、膜の傷つきを起こさずに効果的に洗浄できる。 [0009] As described above, sodium hypochlorite, chlorine dioxide, at the same time as the backwashing by liquid or gas containing at least one or more of hydrogen peroxide, by introducing a gas into the raw water side, causing the damage of film It can be effectively cleaned without. 以下各々詳細に述べる。 Hereinafter described each in detail.

【0010】[多孔膜]多孔膜としては、膜の素材として、ポリエチレン、ポリプロピレン、ポリブテン等のポリオレフィン;テトラフルオロエチレン−パーフルオロアルキルビニルエーテル共重合体(PFA)、テトラフルオロエチレン−ヘキサフルオロプロピレン共重合体(FEP)、テトラフルオロエチレン−ヘキサフルオロプロピレン−パーフルオロアルキルビニルエーテル共重合体(EPE)、テトラフルオロエチレン−エチレン共重合体(ETFE)、ポリクロロトリフルオロエチレン(PCTFE)、クロロトリフルオロエチレン−エチレン共重合体(ECTFE)、ポリフッ化ビニリデン(P [0010] [membrane] The porous membrane, as a material of films, polyethylene, polypropylene, polyolefins polybutene; tetrafluoroethylene - perfluoroalkyl vinyl ether copolymer (PFA), tetrafluoroethylene - hexafluoropropylene copolymerization coalescence (FEP), tetrafluoroethylene - hexafluoropropylene - perfluoroalkyl vinyl ether copolymer (EPE), tetrafluoroethylene - ethylene copolymer (ETFE), poly polychlorotrifluoroethylene (PCTFE), chlorotrifluoroethylene - ethylene copolymer (ECTFE), polyvinylidene fluoride (P
VDF)、ポリ4フッ化エチレン(PTFE)等のフッ素系樹脂;ポリスルホン、ポリエーテルスルホン、ポリエーテルケトン、ポリエーテルエーテルケトン、ポリフェニレンスルフィド等のスーパーエンジニアリングプラスチック;酢酸セルロース、エチルセルロース等のセルロース類;ポリアクリロニトリル、ポリビニルアルコールの単独及びこれらの混合物、また、セラミック等の無機膜が挙げられる。 VDF), fluorine-based resins such as polytetrafluoroethylene (PTFE); polysulfone, polyether sulfone, polyether ketone, polyether ether ketone, super engineering plastics such as polyphenylene sulfide; cellulose acetate, cellulose such as ethylcellulose; acrylonitrile, alone and mixtures of these polyvinyl alcohols also include inorganic film such as a ceramic. 特に、フッ素系樹脂性膜、無機膜が、耐酸化性に優れるため好ましいが、特に、ポリフッ化ビニリデン(PVDF)膜を使用すれば好ましい。 In particular, fluorine-based resin film, an inorganic film, but preferred because it is excellent in oxidation resistance, particularly preferred when using polyvinylidene fluoride (PVDF) membrane.

【0011】このような多孔膜のうち、その孔径領域が逆浸透膜、ナノフィルター、限外濾過(UF)膜、精密濾過(MF)膜であるものが使用し得るが、基本的に高い濾過流量を有する、限外濾過(UF)膜、精密濾過(MF)膜を使用するのが好ましく、特に、精密濾過(MF)膜を使用するのが好ましい。 [0011] Among such porous membranes, the pores diameter region is reverse osmosis, nano-filtration, ultrafiltration (UF) membrane, but those which are microfiltration (MF) membrane can be used, essentially high filtration have a flow rate, it is preferred to use an ultrafiltration (UF) membranes, microfiltration (MF) membrane, particularly, it is preferable to use a microfiltration (MF) membrane. 例えば、平均孔径が0.001〜1μmの膜が好ましく、平均孔径0.0 For example, an average pore diameter of preferably film 0.001 to an average pore size of 0.0
5〜1μmの膜がさらに好ましい。 5~1μm of the film is more preferable. 多孔膜の形状としては、中空糸状、平膜状など任意の形状を用いることができるが、単位体積当たりの膜面積が大きくとれる中空糸状が好ましい。 The shape of the porous membrane, a hollow fiber, but may be any shape such as flat membrane, hollow fiber membrane area per unit volume is made large is preferable. 中空糸状膜の形状としては、ストレート中空糸膜、ウェーブがついた中空糸膜などがあるが、ウェーブがついた中空糸膜の方が、濁質の排出性など理由から好ましい。 The shape of the hollow fiber membranes, straight hollow fiber membrane, but the wave is like a hollow fiber membrane with, towards the hollow fiber membranes wave is attached, preferably for reasons such as the discharge of the suspended matter. 一般に、濾過は膜を収納したモジュールを用いて行われる。 Generally, the filtration is performed using a module which houses the membrane.

【0012】[膜モジュール]この発明で使用される膜モジュールは、配管等を介して接続される中空糸膜モジュールに加え、管板のあるタンクや外郭ハウジングに挿入・配置する事によって使用される、カートリッジ型膜モジュールも含まれる。 [0012] [membrane module A membrane module for use in the present invention, in addition to the hollow fiber membrane module which is connected via a pipe or the like, is used by inserting and arranged in the tank and the outer housing with a tubesheet also includes a cartridge type membrane module.

【0013】また、膜モジュールの両側端部接着固定に使用される熱硬化性樹脂の例を挙げると、エポキシ樹脂、ウレタン樹脂、シリコーンゴム等である。 [0013] Examples of the thermosetting resin used in the both side edge portions bonded to the membrane module, epoxy resin, urethane resin, silicone rubber or the like. また、これらの樹脂にシリカ、カーボンブラック、フッ化カーボン等のフィラーを混入させる事により、樹脂隔壁部の強度向上及び硬化収縮の低減をはかっても良い。 Further, the silica to these resins, carbon black, by which mixing a filler such as carbon fluoride may be aimed at reducing the strength of the resin partition walls improve and cure shrinkage. 膜モジュールのモジュールケースに使用される材質を例示すると、ポリエチレン、ポリプロピレン、ポリブテン等のポリオレフィン;ポリテトラフルオロエチレン(PTF To illustrate the material used for the module case of the membrane module, polyethylene, polypropylene, polyolefins polybutene; polytetrafluoroethylene (PTF
E)、PFA、FEP、EPE、ETFE、PCTF E), PFA, FEP, EPE, ETFE, PCTF
E、ECTFE、PVDF等のフッ素系樹脂;ポリ塩化ビニル、ポリ塩化ビニリデン等の塩素樹脂;ポリスルホン樹脂、ポリエーテルスルホン樹脂、ポリアリルスルホン樹脂、ポリフェニルエーテル樹脂、PMMAなどのアクリル樹脂、アクリロニトリル−ブタジエン−スチレン共重合体樹脂(ABS)、アクリロニトリル−スチレン共重合体樹脂、ポリフェニレンサルファイド樹脂、ポリアミド樹脂、ポリカーボネート樹脂、ポリエーテルケトン樹脂、ポリエーテルエーテルケトン樹脂の単独及びこれらの混合物、及び、アルミニウム、ステンレス鋼等の金属が挙げられる。 Polyvinyl chloride, chlorinated resins polyvinylidene chloride;; E, ECTFE, fluorine resin PVDF like polysulfone resins, polyethersulfone resins, polyallyl sulfone resins, polyphenyl ether resin, an acrylic resin such as PMMA, acrylonitrile - butadiene - styrene copolymer resin (ABS), acrylonitrile - styrene copolymer resin, polyphenylene sulfide resin, polyamide resin, polycarbonate resin, polyether ketone resin, polyether ether ketone resin alone and mixtures thereof, and, aluminum, stainless steel metal such as steel and the like.

【0014】[多孔膜の濾過方法]濾過方式としては、 [0014] Filtration system Filtration method of the porous film] is
全量濾過方式でもクロスフロー濾過方式でもよい。 Or a cross-flow filtration in dead end filtration mode. また、加圧濾過方式でも陰圧濾過方式でもよいが、加圧濾過方式がより高い濾過流束が得られるため好ましい。 Moreover, under pressure or in the shade filter press over method in excessive manner, but preferred for higher filtration flux pressure filtration method is obtained. また、内圧濾過、外圧濾過のどちらでもよいが、外圧濾過の方が、エアスクラビングの効果が大きいので好ましい。 Further, the internal pressure filtration, but may be either external pressure filtration, who external pressure filtration, since a large effect of air scrubbing preferred.

【0015】[多孔膜の洗浄方法]本発明は、原水側に気体を導入すると同時に、次亜塩素酸ナトリウム、二酸化塩素、過酸化水素のいずれか1つ以上を含む液体または気体によって、膜の濾液側から逆流洗浄するものである。 [0015] The present invention [cleaning method of the porous film], at the same time introducing the gas into the raw water side, sodium hypochlorite, chlorine dioxide, either by liquid or gas containing one or more of hydrogen peroxide, the film it is intended to backwashing from the filtrate side. 液体と気体の混合物を用いて逆流洗浄することも含まれる。 Also included be backwashed with a mixture of liquid and gas. 洗浄操作は濾過を中断して行う。 Washing operation is performed by interrupting the filtering.

【0016】逆流洗浄水への次亜塩素酸ナトリウム、二酸化塩素、過酸化水素等の酸化剤の添加方法は、気体や液体の状態で濾水タンクなどに直接投入しても良いし、 [0016] Sodium hypochlorite to backwash water, a method of adding chlorine dioxide, an oxidizing agent such as hydrogen peroxide, to a state of gas or liquid may be introduced directly, such as in drainage tank,
あるいは水溶液として、濾水タンクから多孔膜に至る配管の途中でエジェクターやラインミキサーを用いて添加しても良い。 Or as an aqueous solution, it may be added by using an ejector or line mixer in the middle of the pipe extending from the drainage tank membrane. 気体状態で導入する場合は、逆洗タンクの適宜位置に設けた散気管等を介して行えば良い。 When introduced in gaseous state it may be carried out through the diffusion pipe or the like provided at an appropriate position of the backwash tank. あるいはUチューブ式を用いることもできる。 Alternatively it is also possible to use a U-tube. また、他の構成として、多孔膜に逆流洗浄水を誘導する管の途中で、エジェクター方式またはラインミキシング方式で気体を添加しても良い。 Further, as another configuration, in the middle of the tube to induce backwash water to the porous membrane, it may be added a gas in the ejector system or line-mixing method.

【0017】逆流洗浄水中の酸化剤の濃度は、0.05 [0017] The concentration of the backwash water of the oxidizing agent, 0.05
mg/リットル以上50重量%以下の範囲が好ましい。 mg / l or more 50 wt% or less is preferable.
これより濃度が低い場合は、酸化が十分に進まないため、洗浄効果が十分に得られ難い。 , Below which the concentration is low, the oxidation does not proceed sufficiently, the cleaning effect can hardly be obtained sufficiently. 一方、濃度がこの範囲を超えると、薬品のコストが高くなりすぎる。 On the other hand, if the concentration exceeds this range, the cost of chemicals is too high. 濃度範囲は、好ましくは0.1mg/リットル以上20重量% Concentration ranges, more preferably 0.1mg / l 20 wt%
以下、さらに好ましくは0.1mg/リットル以上10 Or less, more preferably 0.1mg / l or more 10
重量%以下である。 % By weight or less. 濾過とエアスクラビング、逆流洗浄のそれぞれの時間は、適宜選択出来、濾過流量の回復性と、濾過水の回収率を勘案して、適宜決めればよい。 Filtration and air scrubbing, each time back washing, can be appropriately selected, and the recovery of the filtration flow, in consideration of the recovery of filtered water may be appropriately determined. 通常、洗浄と洗浄の間の濾過時間の1/10000〜1/ Normally, the filtration time between washes 1 / 10,000 to 1 /
5の時間をエアスクラビング、逆流洗浄の時間にあてる事が好ましい。 5 of time the air scrubbing, it is preferable to devote the time of backwashing. 1/10000より頻度が少ないと洗浄効果が少なく、1/5より頻度が多いと、濾水の回収率が悪くなり、好ましくない。 Less cleaning effect and less frequent than 1/10000, the frequency from 1/5 is large, the recovery rate of the drainage is deteriorated, unfavorably.

【0018】気体の導入は、膜面の原水側に気体を送り込み、膜面を振動させることにより膜の洗浄を行うものである。 [0018] The introduction of gas is fed to the gas raw water side of the membrane surface, it is intended to clean the membrane by vibrating the membrane surface. 本発明においては、膜面に吸着した有機物が逆流洗浄水に含まれる酸化剤により分解あるいは変性されて非吸着性物質となるため、膜の孔を閉塞する非吸着性の物質(有機物、無機物)が、気体の導入により有効にふるい落とされ、大きな洗浄効果が得られる。 In the present invention, since the organic substances adsorbed on the membrane surface is decomposed or modified by non-adsorbing material by an oxidizing agent contained in the backwash water, non-adsorptive substance which closes the pores of the membrane (organic, inorganic) but effectively be screened out by the introduction of gas, a large cleaning effect is obtained. エアスクラビングの供給エアーの単位時間あたりの流量は標準状態において、単位時間あたりの濾過流量の0.1〜20 In d ask flow standard state per unit of feed air time of the rubbing, per unit time of the filtration flow rate from 0.1 to 20
倍の流量を供給するのが好ましく、0.5〜10倍の流量であることがより好ましい。 It is preferred to provide twice the flow rate, and more preferably 0.5 to 10 times the flow rate. これらの流量以下では、 In these flow rates below,
洗浄効果が低く、これら流量以上では、膜の乾燥等が起こる可能性がある。 Cleaning effect is low, these flow rate or more, there is a possibility that the drying of the film takes place.

【0019】逆流洗浄の気体、液体、気体及び液体の単位時間あたりの逆洗流量は、濾水回収率と膜擦れ合い防止とのかね合いから、単位時間あたりの濾過流量の0. The backwash flow rate per unit of backwashing of gases, liquids, gases and liquids times 0 tradeoff between drainage recovery and film rubbing prevention, per unit time of the filtration flow.
01〜10倍の流量が好ましく、0.1〜3倍の流量が特に好ましい。 Preferably 01 to 10 times the flow rate, particularly preferably 0.1 to 3 times the flow rate. これら逆洗流量より低いと、膜の擦れ合いを防止する効果が低く、洗浄の効果も低くなり、これら単位時間あたりの逆洗流量より、流量が高いと、濾水の回収率低くなり、好ましくない。 Below these backwash flow rate, less effect of preventing rubbing of the film, the effect of washing becomes lower than the backwash flow rate per these unit time, the flow rate is high, becomes recovery of drainage low, preferably Absent.

【0020】本発明によれば、原水側に気体を導入する際は常に逆流洗浄と同時に行うと洗浄効果が高いが、気体の導入(同時に逆流洗浄)に先立ち逆流洗浄のみを行っても良い。 According to the present invention, although the cleaning effect and do always backwash at the same time high when introducing a gas into the raw water side, the introduction of gas may be performed only backwash prior to (simultaneously backwashing). あるいは気体の導入(同時に逆流洗浄)を行った後、逆流洗浄のみを行っても良い。 Or after the introduction of gas (at the same time back washing) may be performed only backwashing. さらに、同時に原水を導入しながら気体を導入し同時に逆流洗浄しても良いし、原水を導入せずに行っても良い。 Furthermore, it may be simultaneously backwashed by introducing a gas while introducing raw water at the same time, it may be performed without introducing raw water. あるいは、 Alternatively,
これらを交互に組み合わせても良い。 It may be a combination of these in turn. 気体の導入(同時に逆流洗浄)に先立ち原水のみ導入を行っても良い。 The introduction of gas may be performed only introduced raw water prior to (simultaneously backwashing). あるいは気体の導入(同時に逆流洗浄)を行った後原水のみ導入を行っても良い。 Alternatively the introduction of the gas (at the same time back washing) may be performed only introduced raw water after. 本発明は、上述のごとく構成したので、高い膜濾過流束で、高品質の処理水が得られる。 The present invention, since the above structure, a high membrane filtration flux, high quality treated water can be obtained.

【0021】 [0021]

【発明の実施の形態】以下、本発明を実施例を用いて説明する。 BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, will be explained with reference to the present invention embodiment.

【0022】 [0022]

【実施例1】原水1として、濁度が1〜5度、水温が1 As Example 1] Raw water 1, turbidity 1-5 degrees, the water temperature is 1
2〜15℃の河川表流水を用いた。 Using the river surface water of 2~15 ℃. 図1に示すように、 As shown in FIG. 1,
原水1は循環タンク2を経て原水供給ポンプ3により膜モジュール4へ圧送され、得られた濾過水は濾水タンク5に貯められる。 Raw water 1 is pumped into the membrane module 4 by the raw water feed pump 3 through the circulation tank 2, resulting filtered water is accumulated in the drainage tank 5. 逆洗時に、濾水タンク5中の濾過水は逆洗ポンプ6により膜モジュール4に送られるが、この途中の配管で、酸化剤タンク8に貯められた次亜塩素酸ナトリウム水溶液を、酸化剤送液ポンプ9を用いてラインミキサーを使用して注入した。 During backwashing, filtered water in drainage tank 5 is fed to the membrane module 4 by the backwash pump 6, in this middle of the pipe, a sodium hypochlorite solution which is accumulated in the oxidizer tank 8, oxidizing agent It was injected using a line mixer using a liquid feed pump 9. また、エアーバブリングは、コンプレッサー7で発生した空気を、膜モジュール4の原水側(1次側)へ供給して行った。 Further, air bubbling is the air generated by a compressor 7, was performed by supplying the raw water side of the membrane module 4 (primary side).

【0023】膜モジュール4は、特開平3−21553 [0023] The membrane module 4, JP-A-3-21553
5号公報に基づいて作製した内径が0.7mmφ、外径が1.25mmφ、平均孔径0.1μmのPVDF(ポリフッ化ビニリデン)製中空糸状精密濾過(MF)膜を1m長、3インチ径のPVC(ポリ塩化ビニル)ケーシングに納めた外圧式モジュールである。 5 JP inner diameter which is manufactured based on the 0.7Mmfai, outer diameter 1.25Mmfai, an average pore diameter of 0.1 [mu] m PVDF (polyvinylidene fluoride) hollow filament microfiltration (MF) membrane 1m length, a diameter of 3 inches PVC is a external pressure type module which dedicated to (polyvinyl chloride) casing. 当該モジュールの膜面積は7.0m 2 、モジュール濾過圧が50kPa Membrane area 7.0 m 2 of the module, the module filtration pressure 50kPa
の時の清澄水濾過流束は毎時1.8m 3である。 The clarified water filtration flux at the time of an hour 1.8m 3.

【0024】濾過は膜モジュール4へ原水1を一定圧力で供給する定圧濾過とし、また、膜濾過水量と循環水量の比を1対1としたクロスフロー方式で行った。 [0024] Filtration is the constant pressure filtration supplying raw water 1 to the membrane module 4 at a constant pressure, was also carried out in a cross flow method in which the ratio of the circulating water and the membrane filtration water 1: 1 and. 運転条件は、濾過を20分間行った後、次亜塩素酸ナトリウム濃度3mg/リットルの次亜塩素酸ナトリウム含有濾水による逆流洗浄を20秒間行うという操作を繰り返し、 Operating conditions, after the filtration 20 min, backwashing with sodium hypochlorite containing drainage sodium hypochlorite concentration 3 mg / l repeat an operation of performing 20 seconds,
1時間毎に次亜塩素酸ナトリウム濃度3mg/リットルの次亜塩素酸ナトリウム含有濾過水による逆流洗浄と毎時2Nm 3の空気によるエアースクラビングを同時に2 Every hour to the air scrubbing with air backwashing and hour 2 Nm 3 with sodium hypochlorite containing filtered water sodium hypochlorite concentration 3 mg / l at the same time 2
分間行った。 Minutes were carried out.

【0025】上記運転条件で1ヶ月間運転した後の膜濾過水量は、4.5m 3 /m 2 /日であった。 [0025] The membrane filtration water after operating for one month in the above operating conditions, was at 4.5m 3 / m 2 / day. また、運転後の膜モジュールを解体し、単糸を次亜塩素酸ナトリウムと苛性ソーダの混合液と蓚酸と硝酸の混合液で薬品洗浄した後、純水透水量を測定したところ、未使用の膜の透水量の97%に相当する透水量であり、膜外表面を倍率5,000倍の走査型電子顕微鏡で観察した結果、膜の外表面の傷つきは軽微であった。 Furthermore, dismantling membrane module after the operation, after chemical cleaning with a mixture of mixture and oxalic acid and nitric acid having a single fiber of sodium and caustic soda hypochlorite, it was measured pure water permeation amount, unused film of a water permeation amount corresponding to 97% of water permeability, result of observation of the outer surface of the membrane at a magnification of 5,000 times of a scanning electron microscope, damage of the outer surface of the membrane it was insignificant.

【0026】 [0026]

【実施例2】実施例1において、膜濾過の運転条件を、 In Example 2 Example 1, the operating conditions of the membrane filtration,
濾過を60分間行った後、次亜塩素酸ナトリウム濃度3 After filtration 60 min, sodium hypochlorite concentration 3
mg/リットル含有濾過水による逆流洗浄と空気を用いたエアースクラビングを同時に2分間行う運転方式に変更した。 It was changed to the operation mode to perform air scrubbing simultaneously for 2 minutes using a backwashing and air by mg / l containing filtered water. 12ヶ月後の膜濾過流量は4.3m 3 /m 2 Membrane filtration flow rate after 12 months 4.3m 3 / m 2 /
日であった。 It was in the day. また、運転後の膜モジュールを解体し、単糸を次亜塩素酸ナトリウムと苛性ソーダの混合液と蓚酸と硝酸の混合液で薬品洗浄した後、純水透水量を測定したところ、未使用の膜の透水量の95%に相当する透水量であり、膜外表面を倍率5,000倍の走査型電子顕微鏡で観察した結果、膜の外表面の傷つきは軽微であった。 Furthermore, dismantling membrane module after the operation, after chemical cleaning with a mixture of mixture and oxalic acid and nitric acid having a single fiber of sodium and caustic soda hypochlorite, it was measured pure water permeation amount, unused film of a water permeation amount corresponding to 95% of water permeability, result of observation of the outer surface of the membrane at a magnification of 5,000 times of a scanning electron microscope, damage of the outer surface of the membrane it was insignificant.

【0027】 [0027]

【実施例3】実施例1において、膜濾過の運転条件を、 In Example 3 Example 1, the operating conditions of the membrane filtration,
次亜塩素酸ナトリウム濃度3mg/リットル含有濾過水による逆流洗浄に変えて、二酸化塩素濃度3mg/リットル含有濾過水を用いて実施例1と同様の実験を行った。 Instead of the backwashing with sodium concentration 3 mg / liter containing filtered water hypochlorite, the same experiment was conducted as in Example 1 using chlorine dioxide concentration 3 mg / liter containing filtered water. 1ヶ月後の膜濾過流量は4.5m 3 /m 2 /日であった。 Membrane filtration flow rate after one month was with 4.5m 3 / m 2 / day. また、運転後の膜モジュールを解体し、単糸を次亜塩素酸ナトリウムと苛性ソーダの混合液と蓚酸と硝酸の混合液で薬品洗浄した後、純水透水量を測定したところ、未使用の膜の透水量の97%に相当する透水量であり、膜外表面を倍率5,000倍の走査型電子顕微鏡で観察した結果、膜の外表面の傷つきは軽微であった。 Furthermore, dismantling membrane module after the operation, after chemical cleaning with a mixture of mixture and oxalic acid and nitric acid having a single fiber of sodium and caustic soda hypochlorite, it was measured pure water permeation amount, unused film of a water permeation amount corresponding to 97% of water permeability, result of observation of the outer surface of the membrane at a magnification of 5,000 times of a scanning electron microscope, damage of the outer surface of the membrane it was insignificant.

【0028】 [0028]

【実施例4】実施例1において、膜濾過の運転条件を、 In Example 4 Example 1, the operating conditions of the membrane filtration,
次亜塩素酸ナトリウム濃度3mg/リットル含有濾過水による逆流洗浄に変えて、過酸化水素濃度3mg/リットル含有濾過水を用いて実施例1と同様の実験を行った。 Instead of the backwashing with sodium concentration 3 mg / liter containing filtered water hypochlorite, the same experiment was conducted as in Example 1 using a hydrogen peroxide concentration 3 mg / liter containing filtered water. 12ヶ月後の膜濾過流量は4.1m 3 /m 2 /日であった。 Membrane filtration flow rate after 12 months was in 4.1m 3 / m 2 / day. また、運転後の膜モジュールを解体し、単糸を次亜塩素酸ナトリウムと苛性ソーダの混合液と蓚酸と硝酸の混合液で薬品洗浄した後、純水透水量を測定したところ、未使用の膜の透水量の97%に相当する透水量であり、膜外表面を倍率5,000倍の走査型電子顕微鏡で観察した結果、膜の外表面の傷つきは軽微であった。 Furthermore, dismantling membrane module after the operation, after chemical cleaning with a mixture of mixture and oxalic acid and nitric acid having a single fiber of sodium and caustic soda hypochlorite, it was measured pure water permeation amount, unused film of a water permeation amount corresponding to 97% of water permeability, result of observation of the outer surface of the membrane at a magnification of 5,000 times of a scanning electron microscope, damage of the outer surface of the membrane it was insignificant.

【0029】 [0029]

【比較例1】実施例2において、次亜塩素酸ナトリウム含有濾過水による逆流洗浄と空気を用いたエアースクラビングを同時に行うのに換えて、エアーのみのスクラビングを行って、実施例2と同様の実験を行った。 In Comparative Example 1 Example 2, instead to simultaneously perform air scrubbing with backwashing air with sodium containing filtrate hypochlorite, performs scrubbing air only, as in Example 2 experiments were carried out. 6ヶ月後の膜濾過流量は2.5m 3 /m 2 /日であった。 Membrane filtration flow rate after six months was at 2.5m 3 / m 2 / day. また、運転後の膜モジュールを解体し、単糸を次亜塩素酸ナトリウムと苛性ソーダの混合液と蓚酸と硝酸の混合液で薬品洗浄した後、純水透水量を測定したところ、未使用の膜の透水量の80%に相当する透水量であった。 Furthermore, dismantling membrane module after the operation, after chemical cleaning with a mixture of mixture and oxalic acid and nitric acid having a single fiber of sodium and caustic soda hypochlorite, it was measured pure water permeation amount, unused film was water permeability corresponding to 80% of the water permeation rate. 膜外表面を倍率5,000倍の走査型電子顕微鏡で観察したところ、膜表面が荒れ、膜表面の開孔の一部が閉塞しており、透過水量の低下の要因と推定された。 When the membrane outer surface was observed at a magnification of 5,000 times of a scanning electron microscope, roughening the film surface, and closed part of the opening of the film surface was estimated to cause a decrease in permeate flow rate.

【0030】 [0030]

【比較例2】実施例2において、次亜塩素酸ナトリウム含有濾過水による逆流洗浄と空気を用いたエアースクラビングを同時に行うのに換えて、濾過水による逆流洗浄と空気を用いたエアースクラビングを同時に行って、同様の実験を行った。 In Comparative Example 2] Example 2, instead to simultaneously perform air scrubbing with backwashing air with sodium hypochlorite containing filtered water, the air scrubbing with backwashing and air by filtered water at the same time go and was subjected to the same experiment. 3ヶ月後の膜濾過流量は3.5m 3 Membrane filtration flow rate after 3 months 3.5m 3
/m 2 /日であった。 / M was in 2 / day. また、運転後の膜モジュールを解体し、単糸を次亜塩素酸ナトリウムと苛性ソーダの混合液と蓚酸と硝酸の混合液で薬品洗浄した後、純水透水量を測定したところ、未使用の膜の透水量の93%に相当する透水量であった。 Furthermore, dismantling membrane module after the operation, after chemical cleaning with a mixture of mixture and oxalic acid and nitric acid having a single fiber of sodium and caustic soda hypochlorite, it was measured pure water permeation amount, unused film It was water permeability equivalent to 93% of the water permeation rate. 膜外表面を倍率5,000倍の走査型電子顕微鏡で観察したところ、膜の外表面の傷つきは軽微であった。 When the membrane outer surface was observed at a magnification of 5,000 times of a scanning electron microscope, damage of the outer surface of the membrane were insignificant.

【0031】 [0031]

【発明の効果】本発明によれば、膜を傷つけずに効果的に洗浄を行う事ができ、この結果、長期間に渡って高い膜濾過流速を維持することが可能である。 According to the present invention, it can be carried out effectively cleaned without damaging the film, as a result, it is possible to maintain a high membrane filtration flow rate over a long period of time.

【図面の簡単な説明】 BRIEF DESCRIPTION OF THE DRAWINGS

【図1】本発明の膜の洗浄方法を組み込んだ処理フローの一例を示したものである。 [1] illustrates an example of a process flow incorporating the cleaning method of the film of the present invention.

Claims (1)

    【特許請求の範囲】 [The claims]
  1. 【請求項1】 多孔膜の洗浄方法において、原水側に気体を導入して膜を揺動させると同時に、濾液側から、加圧した次亜塩素酸ナトリウム、二酸化塩素、過酸化水素の少なくとも1以上を含む液体または気体で逆流洗浄することを特徴とする膜を洗浄する方法。 1. A method of cleaning a porous membrane, and at the same time swinging the film by introducing a gas into the raw water side, from the filtrate side, pressurized sodium hypochlorite, chlorine dioxide, at least one of hydrogen peroxide method of cleaning a film, characterized by backwashing with liquid or gas containing more.
JP25777499A 1999-09-10 1999-09-10 Method for washing membrane Pending JP2001079366A (en)

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Cited By (39)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2006012691A1 (en) * 2004-08-04 2006-02-09 U.S. Filter Wastewater Group, Inc. Chemical and process for cleaning membranes
JP2006263584A (en) * 2005-03-24 2006-10-05 Ngk Insulators Ltd Method for cleaning membrane filtration apparatus
CN100566802C (en) 2004-08-04 2009-12-09 西门子水技术公司 Chemicals and method for cleaning film
JP2010046587A (en) * 2008-08-20 2010-03-04 Toyobo Co Ltd Hollow fiber membrane module
US7972493B2 (en) 2007-07-27 2011-07-05 Gore Enterprise Holdings, Inc. Filter wash for chloralkali process
WO2011122289A1 (en) 2010-03-30 2011-10-06 東レ株式会社 Method for cleaning separation membrane module, and method for fresh water generation
WO2012057188A1 (en) 2010-10-29 2012-05-03 東レ株式会社 Fresh water generation method and fresh water generation device
US8182687B2 (en) 2002-06-18 2012-05-22 Siemens Industry, Inc. Methods of minimising the effect of integrity loss in hollow fibre membrane modules
US8268176B2 (en) 2003-08-29 2012-09-18 Siemens Industry, Inc. Backwash
US8287743B2 (en) 2007-05-29 2012-10-16 Siemens Industry, Inc. Membrane cleaning with pulsed airlift pump
US8293098B2 (en) 2006-10-24 2012-10-23 Siemens Industry, Inc. Infiltration/inflow control for membrane bioreactor
US8318028B2 (en) 2007-04-02 2012-11-27 Siemens Industry, Inc. Infiltration/inflow control for membrane bioreactor
WO2013001914A1 (en) 2011-06-29 2013-01-03 東レ株式会社 Washing method for separation membrane module
US8377305B2 (en) 2004-09-15 2013-02-19 Siemens Industry, Inc. Continuously variable aeration
US8382981B2 (en) 2008-07-24 2013-02-26 Siemens Industry, Inc. Frame system for membrane filtration modules
US8496828B2 (en) 2004-12-24 2013-07-30 Siemens Industry, Inc. Cleaning in membrane filtration systems
US8506806B2 (en) 2004-09-14 2013-08-13 Siemens Industry, Inc. Methods and apparatus for removing solids from a membrane module
US8512568B2 (en) 2001-08-09 2013-08-20 Siemens Industry, Inc. Method of cleaning membrane modules
US8518256B2 (en) 2001-04-04 2013-08-27 Siemens Industry, Inc. Membrane module
CN103492054A (en) * 2011-04-25 2014-01-01 东丽株式会社 Method for cleaning membrane module
US8758621B2 (en) 2004-03-26 2014-06-24 Evoqua Water Technologies Llc Process and apparatus for purifying impure water using microfiltration or ultrafiltration in combination with reverse osmosis
US8758622B2 (en) 2004-12-24 2014-06-24 Evoqua Water Technologies Llc Simple gas scouring method and apparatus
US8790515B2 (en) 2004-09-07 2014-07-29 Evoqua Water Technologies Llc Reduction of backwash liquid waste
US8808540B2 (en) 2003-11-14 2014-08-19 Evoqua Water Technologies Llc Module cleaning method
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Cited By (52)

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Publication number Priority date Publication date Assignee Title
US8518256B2 (en) 2001-04-04 2013-08-27 Siemens Industry, Inc. Membrane module
US8512568B2 (en) 2001-08-09 2013-08-20 Siemens Industry, Inc. Method of cleaning membrane modules
US8182687B2 (en) 2002-06-18 2012-05-22 Siemens Industry, Inc. Methods of minimising the effect of integrity loss in hollow fibre membrane modules
US8268176B2 (en) 2003-08-29 2012-09-18 Siemens Industry, Inc. Backwash
US8808540B2 (en) 2003-11-14 2014-08-19 Evoqua Water Technologies Llc Module cleaning method
US8758621B2 (en) 2004-03-26 2014-06-24 Evoqua Water Technologies Llc Process and apparatus for purifying impure water using microfiltration or ultrafiltration in combination with reverse osmosis
WO2006012691A1 (en) * 2004-08-04 2006-02-09 U.S. Filter Wastewater Group, Inc. Chemical and process for cleaning membranes
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US8790515B2 (en) 2004-09-07 2014-07-29 Evoqua Water Technologies Llc Reduction of backwash liquid waste
US8506806B2 (en) 2004-09-14 2013-08-13 Siemens Industry, Inc. Methods and apparatus for removing solids from a membrane module
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US8758622B2 (en) 2004-12-24 2014-06-24 Evoqua Water Technologies Llc Simple gas scouring method and apparatus
US8496828B2 (en) 2004-12-24 2013-07-30 Siemens Industry, Inc. Cleaning in membrane filtration systems
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US9675938B2 (en) 2005-04-29 2017-06-13 Evoqua Water Technologies Llc Chemical clean for membrane filter
US8894858B1 (en) 2005-08-22 2014-11-25 Evoqua Water Technologies Llc Method and assembly for water filtration using a tube manifold to minimize backwash
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US8293098B2 (en) 2006-10-24 2012-10-23 Siemens Industry, Inc. Infiltration/inflow control for membrane bioreactor
US8318028B2 (en) 2007-04-02 2012-11-27 Siemens Industry, Inc. Infiltration/inflow control for membrane bioreactor
US8623202B2 (en) 2007-04-02 2014-01-07 Siemens Water Technologies Llc Infiltration/inflow control for membrane bioreactor
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US8840783B2 (en) 2007-05-29 2014-09-23 Evoqua Water Technologies Llc Water treatment membrane cleaning with pulsed airlift pump
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US8372276B2 (en) 2007-05-29 2013-02-12 Siemens Industry, Inc. Membrane cleaning with pulsed airlift pump
US8287743B2 (en) 2007-05-29 2012-10-16 Siemens Industry, Inc. Membrane cleaning with pulsed airlift pump
US9206057B2 (en) 2007-05-29 2015-12-08 Evoqua Water Technologies Llc Membrane cleaning with pulsed airlift pump
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US7972493B2 (en) 2007-07-27 2011-07-05 Gore Enterprise Holdings, Inc. Filter wash for chloralkali process
US9023206B2 (en) 2008-07-24 2015-05-05 Evoqua Water Technologies Llc Frame system for membrane filtration modules
US8382981B2 (en) 2008-07-24 2013-02-26 Siemens Industry, Inc. Frame system for membrane filtration modules
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US8956464B2 (en) 2009-06-11 2015-02-17 Evoqua Water Technologies Llc Method of cleaning membranes
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US9914097B2 (en) 2010-04-30 2018-03-13 Evoqua Water Technologies Llc Fluid flow distribution device
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WO2012057188A1 (en) 2010-10-29 2012-05-03 東レ株式会社 Fresh water generation method and fresh water generation device
CN103492054B (en) * 2011-04-25 2015-06-03 东丽株式会社 Method for cleaning membrane module
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WO2013001914A1 (en) 2011-06-29 2013-01-03 東レ株式会社 Washing method for separation membrane module
US10391432B2 (en) 2011-09-30 2019-08-27 Evoqua Water Technologies Llc Manifold arrangement
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