JP3835686B2

JP3835686B2 - Reverse osmosis membrane element performance evaluation system

Info

Publication number: JP3835686B2
Application number: JP2002103255A
Authority: JP
Inventors: 嘉吉伊藤
Original assignee: Organo Corp
Current assignee: Organo Corp
Priority date: 2002-04-05
Filing date: 2002-04-05
Publication date: 2006-10-18
Anticipated expiration: 2022-04-05
Also published as: JP2003299937A

Description

【０００１】
【発明の属する技術分野】
本発明は、一つのハウジング内に直列に配置された２個の逆浸透膜エレメント検体を、一の被検体液で同時にその性能を評価する逆浸透膜エレメントの性能評価装置に関するものである。
【０００２】
【従来の技術】
従来から各種被処理水の脱塩（脱イオンも含む、以下脱塩および脱イオンを総称して脱塩という）等を目的として逆浸透膜モジュールが用いられている。例えば、半導体デバイスの様な電子部品部材類の洗浄には超純水が使用されるが、超純水を製造する工程には逆浸透膜モジュールが用いられることが多い。一般に当該モジュールに装着されている逆浸透膜エレメントは脱塩の目的で設置されるが、逆浸透膜は全有機体炭素（ＴＯＣ）の除去能力も大きく、ＴＯＣが極力低減された水質が要求される前記電子部品部材類の洗浄工程に用いられる超純水の製造過程では、逆浸透膜モジュールの使用は不可欠といっても過言ではない。
【０００３】
従来から用いられている逆浸透膜モジュールの構造例としては、図４および図５に示したごとく、透過水集水管８０に袋状の逆浸透膜８１をスパイラル状に巻きつけ、その上部を外装体８２で被覆し、その両端はスパイラル状に巻きつけた逆浸透膜８１がせり出すのを防止するために、数本の放射状のリブ８３を有するテレスコープ止め８４が取り付けられている。これらの透過水集水管８０、逆浸透膜８１、外装体８２、テレスコープ止め８４でひとつの逆浸透膜エレメント８５を形成し、夫々の透過水集水管８０をコネクタ（図示せず）で連通して、ハウジング８６内に逆浸透膜エレメント８５を複数個装填する。なお、逆浸透膜エレメント８５の外周とハンジング８６の内周の間に隙間８７が形成されるが、この隙間８７をブラインシール８８で閉塞してある。なおハウジング８６の一端には被処理水をハウジング内部に流入するための被処理水流入管（図示せず）、また他端には透過水集水管８０に連通する処理水管（図示せず）および非透過水管（図示せず）が付設され、ハウジング８６、その内部部品および配管（ノズル）等で逆浸透膜モジュール８９が構成される。
【０００４】
このような構造の逆浸透膜モジュール８９で被処理水を処理する場合は、ハウジング８６の一端からポンプを用いて被処理水を圧入するが、図４において矢線で示したように被処理水はテレスコープ止め８４の各放射状のリブ８３の間を通って最初の逆浸透膜エレメント８５内に侵入し、一部の被処理液は逆浸透膜エレメント８５の膜間を通り抜けて次の逆浸透膜エレメント８５に達し、他部の被処理水は逆浸透膜８１を透過して透過水となり当該透過水は透過水集水管８０に集水される。このようにして逆浸透膜エレメント８５に次々に被処理水が通り抜けて、逆浸透膜を透過しなかった被処理水は非透過水（濃縮水）としてハウジング８６の他端から取出し、また逆浸透膜を透過した透過水は透過水集水管８０を介してハウジング８６外に取出す。
【０００５】
このように、逆浸透膜モジュールによる脱塩は塩類を含む水を、ポンプを用いて逆浸透膜モジュールに圧入するだけで脱塩水が得られ、電気透析法や蒸発法と比較して装置が簡単であり、かつＴＯＣ成分である有機物も除去することができ良好な処理水が得られる。一方、逆浸透膜エレメントは、長期間使用されると、逆浸透膜が各種の無機物あるいは有機物により汚染を受けたりモジュール内の原水の接液部あるいは膜面に微生物が発生するなどして、差圧が上昇したり、透過水量が減少したり、さらには膜の劣化によりその脱塩率が低下するなどの性能低下を起こし、使用が困難となる。このような使用困難と判断された逆浸透膜エレメントはハウジング内から取出され、新品の逆浸透膜エレメントと交換され、取出された逆浸透膜エレメントは産業廃棄物として廃棄される。
【０００６】
逆浸透膜エレメントを産業廃棄物として廃棄処分する場合、処分コストや処分場所の問題がある。この問題を解決するものとして、使用済み逆浸透膜モジュールを回生処理して再使用することが従来から提案されている。脱塩率が低下した逆浸透膜は、逆浸透膜の緻密層が化学的に酸化されてその分子構造が破壊されること等に起因するものであり、元の状態に復帰させることは困難であるが、膜が汚染を受けることにより差圧が上昇したり、透過水量が減少したりした逆浸透膜は、回生処理を施し再使用することができる。すなわち、膜の汚染が原因で性能低下した逆浸透膜モジュールに、酸、アルカリ、クエン酸のような洗浄力の高い有機性薬液を接触させ、ベッセル内や逆浸透膜エレメントの膜面あるいは膜内部に付着沈積した無機物、有機物、微生物スライム等からなる汚染物を脱離するものである。このような回生処理によって、差圧が上昇したりあるいは透過水量が低下した逆浸透膜はその性能を復帰させることができる。
【０００７】
しかし、従来から提案されている使用済み逆浸透膜モジュールの回生処理は、水処理施設内の複数系列の逆浸透膜モジュールにおいて行われるものであり、回生処理に必要な薬液槽、配管、弁、ポンプ等を具備した回生処理設備の設置やその設置場所が必要であること、回生処理に用いる薬液の排液処理装置の設置が必要であること、回生処理装置の稼働率が極めて小さく回生処理設備の投資に見合う採算が取れない等の種々の問題を抱えている。そこで、近年、使用済み逆浸透膜エレメントの回生処理を個々の水処理施設内で行うのではなく、特定の専用の施設内で集中して実施することで、回生処理装置の稼働率を高め、回生処理した逆浸透膜エレメントは要望時には直ちに提供するような、使用済み逆浸透膜エレメントの回収、回生処理および回生処理品の供給にいたる総合的な利用技術の開発が検討されている。
【０００８】
【発明が解決しようとする課題】
このような使用済み逆浸透膜エレメントの回生処理においては、回収された逆浸透膜エレメントの性能を予め調べ、その結果に応じた回生処理を行う必要がある。また、回生処理後においては、回生処理品の回生状態を把握するため、回生後の性能を調べる必要がある。しかし、従来、水処理施設内で使用されている逆浸透膜モジュールから回収された使用済み逆浸透膜エレメントを評価する逆浸透膜エレメントの性能評価装置は未だ提案されていない。また、新品の逆浸透膜エレメントは出荷の際、同様の性能評価が行われるものの、これに用いる性能評価装置は一つのハウジング内に一個の逆浸透膜エレメントを装填したモジュールであるか、あるいは該モジュールの複数個を並列に組付けたものであり、一つのハウジング内に二つの逆浸透膜エレメントを装填し、一つの被検体液で二つの逆浸透膜エレメントを同時に個別の評価が行えるものではない。この場合、一つのハウジングにおいて一つの逆浸透膜エレメント検体の性能評価しかできず、性能評価試験の効率が悪いという問題がある。また、逆浸透膜エレメント検体の性能評価は、水処理施設内で使用される組付け形態と同様の構成で実施するため、例えば図４に示すようにハウジング内に検体である逆浸透膜エレメントを２個装填して逆浸透膜モジュールを構成し、被処理水の代わりに被検体液を供給する形態が考えられる。しかし、この場合、二つの逆浸透膜エレメントの透過水集水管が共通しているため、一の被検体液を圧入して得られる透過水は二つの逆浸透膜エレメントの各透過水の混合水であり、二つの逆浸透膜エレメントの個別の評価を行うことはできない。
【０００９】
従って、本発明の目的は、一つのハウジング内に直列に配置された２個の逆浸透膜エレメント検体を、一の被検体液で同時にその性能を個別に評価する効率の高い逆浸透膜エレメントの性能評価装置を提供するものである。
【００１０】
【課題を解決するための手段】
上記目的を達成するための本発明（１）は、一端側に被検体液管と接続する被検体液流入口及び第１透過水管と接続する第１透過水流出口を有し、他端側に非透過水管と接続する非透過水流出口及び第２透過水管と接続する第２透過水流出口を有するハウジングと、該ハウジングに装填され一端の開口が前記第１透過水流出口に接続する第１透過水集水管を有する第１逆浸透膜エレメント検体と、該ハウジングに装填されかつ該第１逆浸透膜エレメント検体と直列に配置され一端の開口が前記第２透過水流出口に接続する第２透過水集水管を有する第２逆浸透膜エレメント検体とからなり、該第１透過水集水管の他端の開口と該第２透過水集水管の他端の開口は共に封止手段で封止され、一の検体液で二つの逆浸透膜エレメント検体を同時に性能評価する逆浸透膜エレメントの性能評価装置を提供するものである。また、本発明（２）は、前記封止手段が、該第１透過水集水管と該第２透過水集水管を該両集水管内を流れる透過水の互いの流通を遮断する遮蔽部を備える結合手段で結合したものであるか、あるいは該第１透過水集水管及び該第２透過水集水管の他端の両開口を各々エンドキャップで封止したものである前記逆浸透膜エレメントの性能評価装置を提供するものである。また、本発明（３）は、前記ハウジングの中央部に、該第１逆浸透膜エレメント検体の非透過水が流出する中間非透過水流出口を設けた前記逆浸透膜エレメントの性能評価装置を提供するものである。また、本発明（４）は、前記第１逆浸透膜エレメント検体及び前記第２逆浸透膜エレメント検体は、共に使用済み逆浸透膜エレメントである前記逆浸透膜エレメントの性能評価装置を提供するものである。
【００１１】
【発明の実施の形態】
本発明の実施の形態における逆浸透膜エレメントの性能評価装置を図１及び図２を参照して説明する。図１は本実施の形態例における逆浸透膜エレメントの性能評価装置の構造を示す縦断面図、図２はハウジングの端板と逆浸透膜エレメントの透過水集水管との接合状態の一例を示す図である。図１において、逆浸透膜エレメントの性能評価装置１０は、ハウジング１６内に二つの逆浸透膜エレメント検体１５ａ、１５ｂを直列配置に装填し、二つの透過水集水管１９ａ、１９ｂを透過水の流通が遮断されるように封止手段３０で結合し、ハウジング１６に一の被検体液を圧入することで、第１逆浸透膜エレメント検体１５ａから第１透過水を、第２逆浸透膜エレメント検体１５ｂから第２透過水をそれぞれ別個に得るように構成したものである。
【００１２】
すなわち、逆浸透膜エレメントの性能評価装置１０は、一端側に被検体液管（不図示）と接続する被検体液流入口２１及び第１透過水管２２と接続する第１透過水流出口２３を有し、他端側に非透過水管（不図示）と接続する非透過水流出口２４及び第２透過水管２５と接続する第２透過水流出口２６を有するハウジング１６と、ハウジング１６に装填され一端の開口３１ａが第１透過水流出口２３とアダプター２７により接続する第１透過水集水管１９ａを有する第１逆浸透膜エレメント検体１５ａと、ハウジング１６に装填されかつ第１逆浸透膜エレメント検体１５ａと直列に配置され一端の開口３２ａが第２透過水流出口２６とアダプター２８により接続する第２透過水集水管１９ｂを有する第２逆浸透膜エレメント検体１５ｂとから構成され、第１透過水集水管１９ａの他端の開口３１ｂと第２透過水集水管１９ｂの他端の開口３２ｂは共に封止手段３０で封止され、一の被検体液で二つの逆浸透膜エレメント検体１５ａ、１５ｂを同時に評価するものである。また、ハウジング１６の中央部には、必要に応じて設置される第１逆浸透膜エレメント検体１５ａの非透過水が流出する中間非透過水流出口３３が設けられている。なお、図１及び図２に示すように、ハウジング１６の一端側及び他端側の両側部材は、通常、本体の円筒部材とは別部材からなる端板２０であり、一端側の端板２０は第１透過水流出口２３、被検体液流入口２１となる貫通孔を有している。端板２０に形成される第１透過水流出口２３と逆浸透膜エレメントの透過水集水管との接合は、外周面のＯリング溝にＯリング２７３を嵌合させた小径部２７１と、内周面のＯリング溝にＯリング２７４を嵌合させた大径部２７２とからなるアダプター２７を使用して行う。アダプター２７の小径部２７１の外径は第１透過水流出口２３の内径よりやや小さめ、アダプター２７の大径部２７２の内径は逆浸透膜エレメントの第１透過水集水管１９ａの外径よりやや大きめに形成され、第１透過水流出口２３とアダプター２７の小径部２７１の嵌合、及び第１透過水集水管１９ａの先端部１９１ａとアダプター２７の大径部２７２との嵌合はＯリングにより確実に固定される。
【００１３】
封止手段３０としては、第１透過水集水管の他端の開口３１ｂと第２透過水集水管の他端の開口３２ｂを封止するものであれば、特に制限されず、例えば本例のように第１透過水集水管１９ａと第２透過水集水管１９ｂを該両集水管内を流れる透過水の互いの流通を遮断する遮蔽部３５を備える結合手段３４で結合したものであるか、あるいは第１透過水集水管１９ａ及び第２透過水集水管１９ｂの他端の両開口を各々エンドキャップで封止したもの等が挙げられる。本例の結合手段３４は遮蔽部３５を内壁とする円筒体で、遮蔽部３５で区画される左右両側の内周面には図では省略するＯリング溝に嵌合するＯリングが配設され、第１透過水集水管１９ａ及び第２透過水集水管１９ｂと結合手段３４の結合は、円筒体の両側の開口から第１透過水集水管１９ａの他端３１ｂと第２透過水集水管１９ｂの他端３２ｂをＯリングの摩擦に抗して中に圧入することで行われる。
【００１４】
また、封止手段３０において、両集水管の他端３１ｂ、３２ｂの両開口を各々エンドキャップで封止する場合、封止後のエンドキャップの端部同士を当接又は当接に近い状態まで近接させ、被検体液のハウジング１６内への圧入に伴う、第１逆浸透膜エレメント１５ａの移動を防止するようにする。また、封止手段３０の他の例としては、例えば遮蔽部を金属製又は樹脂製のシート板とし、これをフランジ部を有する１対の接合部材で挟み、ネジ類で固定する方法を採ることもできる。この場合、該接合部材と両集水管の他端３１ｂ、３２ｂとの結合は、本例と同様、Ｏリングによる方法を用いることができる。このように、本発明における封止手段３０は、エンドキャップのような分断型、本例である内壁を有する円筒体のような一体型及びシート板をフランジで挟む接続型などいずれの形態であってもよい。
【００１５】
本発明の性能評価装置１０で用いる第１逆浸透膜エレメント検体１５ａ及び第２逆浸透膜エレメント検体１５ｂとしては、特に制限されないが、例えば、半導体デバイスの様な電子部品部材類の洗浄用超純水を製造する工程で使用された逆浸透膜モジュールの逆浸透膜エレメントであって、該使用済みとなった逆浸透膜エレメントの回収、回生処理及び回生処理済み品の供給に至る一連の過程で必要となる性能評価試験における評価対象物である。具体的には、第１逆浸透膜エレメント検体１５ａ及び第２逆浸透膜エレメント検体１５ｂは、使用済みとなって回収された逆浸透膜エレメント又は回生処理後の逆浸透膜エレメントである。使用済みとなって回収された逆浸透膜エレメントの性能評価は回収された逆浸透膜エレメントの性能を予め調べ、その結果に応じて回生処理条件等を定めるために行うものであり、また、回生処理後の逆浸透膜エレメントの性能評価は、回生処理済み品の回生状態を把握し、新たな供給先を決定するために行うものである。
【００１６】
使用済みとは、逆浸透膜エレメントが長期間使用され、逆浸透膜が各種の無機物あるいは有機物により汚染を受けたりモジュール内の原水の接液部あるいは膜面に微生物が発生するなどして、差圧が上昇したり、透過水量が減少したり、さらには膜の劣化によりその脱塩率が多少低下するなどの性能低下を起こし、使用が困難となったものであるか、あるいは、予め定めた所定期間が経過したもの、あるいは、処理水累積量が規定値に達し、数ヶ月後には性能低下が予想されるため、安全を見越してモジュール内から取出されたものである。また、第１逆浸透膜エレメント検体１５ａと第２逆浸透膜エレメント検体１５ｂは、使用履歴が同じものであっても、異なったものであってもよい。
【００１７】
第１逆浸透膜エレメント検体１５ａ及び第２逆浸透膜エレメント検体１５ｂは、本例では使用済みのスパイラル式逆浸透膜エレメントを回収したものであるため、逆浸透膜エレメントの構造は図４および図５に示されるものと同じである。すなわち、図１の第１逆浸透膜エレメント検体１５ａでは第１透過水集水管１９ａに袋状の逆浸透膜１１ａをスパイラル状に巻きつけ、その上部を外装体１２で被覆し、スパイラル状に巻きつけた逆浸透膜１１ａがせり出すのを防止するために、数本の放射状のリブ１３を有するテレスコープ止め１４を両端に取り付けてある。これらの第１透過水集水管１９ａ、逆浸透膜１１ａ、外装体１２、テレスコープ止め１４でひとつの逆浸透膜エレメントを形成する。第２逆浸透膜エレメント検体１５ｂは、第１逆浸透膜エレメント１５ａと同様の構造であるのでその説明を省略する。なお、ハウジング１６に二つの逆浸透膜エレメントを装填した際、第１及び第２の逆浸透膜エレメント１５ａ、１５ｂの外周とハンジング１６の内周の間に隙間１７が形成されるが、この隙間１７をブラインシール１８で閉塞してある。
【００１８】
本例の逆浸透膜エレメントの性能評価装置１０の組付けは、ハウジング１６の一端から順次、各部材を挿入する方法で行われる。挿入方向はブラインシール１８が閉じる方向であり、本例では図１中、ハウジング１６の左端の開口から右方向へ各部材を挿入する。すなわち、右側の端板２０及びアダプター２８を組付けたハウジング１６に、予め封止手段３０を取付けた第２逆浸透膜エレメント検体１５ｂを挿入し、アダプター２８へ圧入することでＯリングによって固定する。次いで、第１逆浸透膜エレメント１５ａを挿入し、集水管の端部を封止手段３０へ圧入することで固定する。次いで、端板２０に予め組付けたアダプター２７に第１透過水集水管の他端１９１ａを圧入し、更に端板２０をハウジング１６に固定することで組付けを完了する（図２参照）。
【００１９】
本発明の逆浸透エレメントの性能評価装置１０の各流入口及び流出口に接続される被検体液管、第１透過水管、第２透過水管、非透過水管及び中間非透過水を通す中間非透過水管の各配管には、流量計、圧力計、導電率計及びＴＯＣ計の少なくともひとつを設置することが、これを用いた計測系を自動化でき、性能評価の迅速化が図れる点で好適である。なお、当該計器類が全くなくとも、前記配管又は該配管から分岐した分岐管から流出する液又は水をサンプリングして当該水質を評価することもできる。
【００２０】
本発明の逆浸透膜エレメントの性能評価装置１０を用いて行う、逆浸透膜エレメントの性能評価項目としては、塩類排除性能や有機物排除性能等の排除性能、所定の測定条件下における透過水量を測定する造水性能及び被検体液供給圧力と非透過水（濃縮水）圧力との差圧であるエレメント差圧が挙げられる。
【００２１】
塩類排除性能は、いわゆる脱塩性能、脱塩率及び塩類排除率であり、塩化ナトリウム溶液等の塩類溶液を被検体液とし、該被検体液中の塩類の排除性能を測定するものである。測定方法としては、例えば、被検体液中の電気導電率と透過水の電気導電率の比を測定する方法、１−（透過水の電気導電率÷被検体液の電気導電率）から塩類排除率を測定する方法、及び次式（１）から塩類排除率を測定する方法が挙げられる。

【００２２】
有機物排除性能は、回収された逆浸透膜エレメントが非常にきれいな場合、逆浸透膜を塩類溶液で汚染させたくない場合等で用いられる評価項目である。測定方法としては、上記塩類排除性能で記載された測定方法において、塩類を有機物に代えて適用すればよい。被検体液として用いられる有機物溶液としては、イソプロピルアルコール溶液、グルコース、ショ糖及びラフィノース等の糖類溶液が挙げられる。有機物濃度はＴＯＣ計で測定される。
【００２３】
造水性能は、所定の測定条件下における透過水の流量を測定し、新品時の流量と比較する。逆浸透膜の表面が汚染されると、水が透過するときの抵抗が増大して透過水量が減少する。新品エレメントの当該数値は、対象となる回収エレメントと同じ型式の新品エレメントの性能値あるいはカタログ値等が使用できる。
【００２４】
エレメント差圧は、被検体液通水時の流路差圧であり、具体的には被検体液供給圧力と非透過水（濃縮水）圧力との差圧である。被処理水や濃縮水が流れる流路が閉塞するとエレメント差圧が上昇する。
【００２５】
本発明の性能評価装置１０を用いて性能評価を行う場合、被検体液の供給圧力及び塩類濃度等は検体である逆浸透膜エレメントの圧力タイプにより決定される。すなわち、運転圧力５．５ＭＰａの高圧膜型の逆浸透膜エレメントでは、塩化ナトリウム濃度が３％の被検体液が用いられ、運転圧力２〜４ＭＰａの中圧膜型の逆浸透膜エレメント、運転圧力１〜２ＭＰａの低圧型逆浸透膜エレメント及び運転圧力０．５〜１ＭＰａの超低圧膜型逆浸透膜エレメントでは、塩化ナトリウム濃度が５００〜２,０００mg/Lの被検体液が用いられる。なお、濃縮水流量は、８インチエレメントの場合８０リットル／分、４インチエレメントの場合２０リットル／分が採用される。
【００２６】
次に、本例の逆浸透膜エレメントの性能評価装置１０を用いて、逆浸透膜エレメント検体の性能を評価する方法の一例を図１及び図３を参照して説明する。図３の性能評価装置１０は、図１の逆浸透膜エレメントの性能評価装置１０の各流入口及び流出口に被検体液管５１、第１透過水管２２、第２透過水管２５、非透過水管５３及び中間非透過水を通す中間非透過水管５５の各配管を接続したものであり、これらの配管には、流量計４１、圧力計４２、導電率計４３及びＴＯＣ計４４がそれぞれ設置されている。図３中、測定圧力を定める、ポンプ、ニードル弁及び切り換え弁等は省略されている。
【００２７】
図１及び図３において、先ずハウジング１６に接続された被検体液管５１からポンプ（不図示）を用いて被検体液を圧入する。図中、矢線で示すように被検体液はテレスコープ止め１４の各放射状のリブ１３の間を通って第１逆浸透膜エレメント検体１５ａ内に侵入し、一部の被検体液は第１逆浸透膜エレメント検体１５ａの膜間を通り抜けて次の第２逆浸透膜エレメント検体１５ｂに達し、他部の被検体液は第１逆浸透膜１１ａを透過して透過水となり当該透過水は第１透過水集水管１９ａに集水され、第１透過水として第１透過水管２２から流出する。次いで、第２逆浸透膜エレメント検体１５ｂに達した被検体液は当該膜間を通り抜けて、逆浸透膜を透過しなかった被検体液は非透過水（濃縮水）としてハウジング１６に接続された非透過水管５３に流出する。また、第２逆浸透膜エレメント検体１５ｂの第２逆浸透膜１１ｂを透過した透過水は第２透過水集水管１９ｂを介して第２透過水管２５からハウジング１６の外に流出する。一方、第１逆浸透膜エレメント検体１５ａの膜間を通り抜け、第２逆浸透膜エレメント検体１５ｂに到達していない中間非透過水は、第２逆浸透膜エレメント検体１５ｂの被検体液であり、中間非透過水管５５へ流出する。
【００２８】
図３によれば、第１逆浸透膜エレメント検体１５ａの第１透過水集水管１９ａと第２逆浸透膜エレメント検体１５ｂの第２透過水集水管１９ｂとは、封止手段３０でこの両集水管を流れる透過水の流通が遮断されているため、第１透過水管２２から得られる第１透過水は第２透過水集水管１９ｂに集められた第２透過水の影響を受けることがなく、第２透過水は第１透過水集水管１９ａに集められた第１透過水の影響を受けることがない。このため、例えば第１逆浸透膜エレメント検体１５ａの塩類排除性能又は有機物排除性能は、被検体液の電気導電率又はＴＯＣと、第１透過水の電気導電率又はＴＯＣを測定することにより求められ、これと同時に、第２逆浸透膜エレメント検体１５ｂの塩類排除性能又は有機物排除性能は、中間非透過水の電気導電率又はＴＯＣと、第２透過水の電気導電率又はＴＯＣを測定することにより求められる。また、例えば第１逆浸透膜エレメント検体１５ａの造水性能は、所定の測定条件下、第１透過水の流量を測定することにより求められ、これと同時に第２逆浸透膜エレメント検体１５ｂの造水性能は、所定の測定条件下、第２透過水の流量を測定することにより求められる。また、例えば第１逆浸透膜エレメント検体１５ａのエレメント差圧は、被検体液の供給圧力と中間非透過水の圧力を測定することにより求められ、これと同時に第２逆浸透膜エレメント検体１５ｂのエレメント差圧は、中間非透過水の供給圧力と非透過水の圧力を測定することにより求められる。なお、中間非透過水流出口３３を設けない場合、例えば被検体液の流量から第１透過水量を差し引いた値を中間非透過水の流量とし、この計算値を測定の基準値として用いればよい。
【００２９】
このような手法により性能が評価された逆浸透膜エレメントは、回生処理前の性能評価の場合、例えば前述したと同じ装置を用いてハウジング内に純水を流入して充分に洗浄され、次いで汚染の程度に応じて決定された条件で回生処理が行なわれる。また、回生処理後の性能評価の場合、純水洗浄後は、その性能評価の値に基づいて回生処理済みエレメントをどのような再使用先に用いるか決定される。
【００３０】
本発明の逆浸透膜エレメントの性能評価装置は、これを二つ以上用いて並列に配設し、一つの被検体液で四つ以上の逆浸透膜エレメント検体を同時に評価するようにしてもよい。また、当該性能評価装置は、前述したように回生処理装置としても使用できるため、例えば切り換え弁の操作により、ハウジングと被検体液管の接続をハウジングと純水供給管又は薬液供給管との接続にすれば、逆浸透膜エレメントの性能評価装置兼回生装置とすることができる。
【００３１】
このように、本発明の逆浸透膜エレメントの性能評価装置１０によれば、ひとつのハウジング内に直列に２個の逆浸透膜エレメント検体を配置しているにもかかわらず、互いの透過水集水管を共通とせず独立にしたため、一の被検体液で同時にその個々の性能を別個に評価することができる。
【００３２】
【発明の効果】
本発明によれば、ひとつのハウジング内に直列に配置された２個の逆浸透膜エレメント検体を、一の被検体液で同時にその性能を個別に評価することができる。このため、逆浸透膜エレメントの性能評価に要する時間を短縮することができる。また、例えば水処理施設内で使用されている逆浸透膜モジュールから回収された使用済み逆浸透膜エレメントを効率よく評価できるため、使用済み逆浸透膜エレメントの回収後の工程である回生処理及び回生処理品の供給等を迅速に行うことができる。
【図面の簡単な説明】
【図１】本発明の実施の形態における逆浸透膜モジュールの性能評価装置の構造を示す縦断面図である。
【図２】ハウジングの端板と逆浸透膜エレメントの透過水集水管との接合状態の一例を示す図である。
【図３】図１の性能評価装置を用いた性能評価方法を説明する図である。
【図４】従来の逆浸透膜モジュールの構造を示す一部を欠いた縦断面図である。
【図５】図３のＡ−Ａ線における縦断面図である。
【符号の説明】
１０逆浸透膜エレメントの性能評価装置
１１ａ、１１ｂ、８１逆浸透膜
１４、８４テレスコープ止め
１５ａ第１逆浸透膜エレメント検体
１５ｂ第２逆浸透膜エレメント検体
１６、８６ハウジング
１８、８８ブラインシール
１９ａ第１透過水集水管
１９ｂ第２透過水集水管
２０端板
２１被検体液流入口
２２第１透過水管
２３第１透過水流出口
２４非透過水流出口
２５第２透過水管
２６第２透過水流出口
３０封止手段
４１流量計
４２圧力計
４３導電率計
４４ＴＯＣ計
５１被検体液管
５３非透過水管
５５中間非透過水管[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a reverse osmosis membrane element performance evaluation apparatus for evaluating the performance of two reverse osmosis membrane element specimens arranged in series in one housing at the same time with one analyte liquid.
[0002]
[Prior art]
Conventionally, reverse osmosis membrane modules have been used for the purpose of desalting various types of water to be treated (including deionization, hereinafter referred to as demineralization and deionization collectively). For example, ultrapure water is used for cleaning electronic component members such as semiconductor devices, but a reverse osmosis membrane module is often used in a process for producing ultrapure water. In general, the reverse osmosis membrane element mounted on the module is installed for the purpose of desalination, but the reverse osmosis membrane has a large ability to remove all organic carbon (TOC), and water quality with TOC reduced as much as possible is required. It is no exaggeration to say that the use of a reverse osmosis membrane module is indispensable in the production process of ultrapure water used in the cleaning process of the electronic component members.
[0003]
As an example of the structure of a reverse osmosis membrane module used conventionally, as shown in FIGS. 4 and 5, a bag-like reverse osmosis membrane 81 is spirally wound around a permeate water collecting pipe 80, and the upper part is externally wrapped. A telescope stopper 84 having several radial ribs 83 is attached to prevent the reverse osmosis membrane 81 wound in a spiral shape from being covered and covered with the body 82. The permeate water collecting pipe 80, the reverse osmosis membrane 81, the exterior body 82, and the telescope stopper 84 form one reverse osmosis membrane element 85, and each permeate water collecting pipe 80 is communicated with a connector (not shown). Then, a plurality of reverse osmosis membrane elements 85 are loaded in the housing 86. A gap 87 is formed between the outer periphery of the reverse osmosis membrane element 85 and the inner periphery of the handling 86, and the gap 87 is closed with a brine seal 88. A treated water inflow pipe (not shown) for allowing treated water to flow into the housing is provided at one end of the housing 86, and a treated water pipe (not shown) communicating with the permeate water collecting pipe 80 is provided at the other end. A permeated water pipe (not shown) is attached, and a reverse osmosis membrane module 89 is constituted by the housing 86, its internal components, piping (nozzles) and the like.
[0004]
When the water to be treated is treated with the reverse osmosis membrane module 89 having such a structure, the water to be treated is press-fitted from one end of the housing 86 using a pump. However, as shown by the arrow in FIG. Enters between the radial ribs 83 of the telescope stopper 84 and enters the first reverse osmosis membrane element 85, and a part of the liquid to be treated passes between the membranes of the reverse osmosis membrane element 85 to the next reverse osmosis. The water to be treated reaches the membrane element 85, and other treated water passes through the reverse osmosis membrane 81 to become permeated water, and the permeated water is collected in the permeated water collecting pipe 80. In this way, the water to be treated passes through the reverse osmosis membrane element 85 one after another, and the water to be treated that has not permeated the reverse osmosis membrane is taken out from the other end of the housing 86 as non-permeated water (concentrated water). The permeated water that has passed through the membrane is taken out of the housing 86 through the permeated water collecting pipe 80.
[0005]
In this way, desalination using reverse osmosis membrane modules provides salt water just by press-fitting salt-containing water into the reverse osmosis membrane module using a pump, and the device is simpler than electrodialysis or evaporation. In addition, an organic substance that is a TOC component can also be removed, and good treated water can be obtained. On the other hand, when a reverse osmosis membrane element is used for a long period of time, the reverse osmosis membrane is contaminated with various inorganic substances or organic substances, or microorganisms are generated at the wetted part of the raw water in the module or the membrane surface. It becomes difficult to use due to a decrease in performance such as an increase in pressure, a decrease in the amount of permeated water, and a decrease in the desalination rate due to deterioration of the membrane. The reverse osmosis membrane element determined to be difficult to use is taken out from the housing, replaced with a new reverse osmosis membrane element, and the taken out reverse osmosis membrane element is discarded as industrial waste.
[0006]
When the reverse osmosis membrane element is disposed of as industrial waste, there are problems of disposal cost and disposal location. In order to solve this problem, it has been conventionally proposed to regenerate and reuse a used reverse osmosis membrane module. A reverse osmosis membrane with a reduced desalination rate is due to the fact that the dense layer of the reverse osmosis membrane is chemically oxidized and its molecular structure is destroyed, and it is difficult to restore it to its original state. However, a reverse osmosis membrane whose differential pressure has increased or the amount of permeated water has decreased due to contamination of the membrane can be subjected to regeneration treatment and reused. That is, a reverse osmosis membrane module whose performance has deteriorated due to membrane contamination is brought into contact with an organic chemical solution having a high detergency such as acid, alkali or citric acid, and the membrane surface of the vessel or the reverse osmosis membrane element or inside the membrane It removes contaminants composed of inorganic substances, organic substances, microbial slime, etc. deposited and deposited on. By such regenerative treatment, the reverse osmosis membrane in which the differential pressure increases or the permeated water amount decreases can restore its performance.
[0007]
However, the regenerative treatment of used reverse osmosis membrane modules that has been conventionally proposed is performed in a plurality of series of reverse osmosis membrane modules in a water treatment facility, and chemical tanks, pipes, valves, It is necessary to install a regenerative treatment facility equipped with a pump, etc., its installation location, the need to install a drainage treatment device for chemicals used for regenerative treatment, and the regenerative treatment facility with a very low operation rate of the regenerative treatment device There are various problems such as not being able to make a profit for the investment. Therefore, in recent years, the regenerative treatment of used reverse osmosis membrane elements is not performed in individual water treatment facilities, but concentrated in specific dedicated facilities, increasing the operation rate of regenerative treatment equipment, Development of a comprehensive application technology for collecting used reverse osmosis membrane elements, regenerating treatment, and supplying regeneratively treated products, which are immediately provided upon request, is provided.
[0008]
[Problems to be solved by the invention]
In the regeneration treatment of such a used reverse osmosis membrane element, it is necessary to examine the performance of the collected reverse osmosis membrane element in advance and perform the regeneration treatment according to the result. In addition, after the regenerative process, it is necessary to examine the performance after the regenerative process in order to grasp the regenerative state of the regenerative processed product. However, a reverse osmosis membrane element performance evaluation apparatus for evaluating a used reverse osmosis membrane element collected from a reverse osmosis membrane module used in a water treatment facility has not been proposed yet. In addition, although a new reverse osmosis membrane element is subjected to the same performance evaluation at the time of shipment, the performance evaluation apparatus used for this is a module in which one reverse osmosis membrane element is loaded in one housing, or the Multiple modules are assembled in parallel, and two reverse osmosis membrane elements are loaded in one housing, and two reverse osmosis membrane elements can be individually evaluated simultaneously with one analyte liquid. Absent. In this case, there is a problem that only the performance evaluation of one reverse osmosis membrane element specimen can be performed in one housing, and the efficiency of the performance evaluation test is poor. In addition, since the performance evaluation of the reverse osmosis membrane element specimen is performed with the same configuration as the assembly form used in the water treatment facility, for example, as shown in FIG. 4, the reverse osmosis membrane element as a specimen is placed in the housing. A configuration is possible in which two are loaded to form a reverse osmosis membrane module and the specimen liquid is supplied instead of the water to be treated. However, in this case, since the permeate water collecting pipes of the two reverse osmosis membrane elements are common, the permeate obtained by press-fitting one analyte liquid is a mixed water of each permeate of the two reverse osmosis membrane elements. Thus, it is not possible to perform separate evaluation of the two reverse osmosis membrane elements.
[0009]
Accordingly, an object of the present invention is to provide a highly efficient reverse osmosis membrane element that evaluates the performance of two reverse osmosis membrane element specimens arranged in series in one housing at the same time with one analyte liquid. A performance evaluation apparatus is provided.
[0010]
[Means for Solving the Problems]
In order to achieve the above object, the present invention (1) has an analyte liquid inlet connected to the analyte liquid pipe on one end side and a first permeate outlet connected to the first permeate pipe, on the other end side. A housing having a non-permeate water outlet connected to the non-permeate water pipe and a second permeate water outlet connected to the second permeate pipe, and a first permeate loaded in the housing and having an opening at one end connected to the first permeate water outlet A first reverse osmosis membrane element specimen having a water collection pipe, and a second permeated water collection loaded in the housing and arranged in series with the first reverse osmosis membrane element specimen and having an opening at one end connected to the second permeate outlet. A second reverse osmosis membrane element specimen having a water pipe, and the opening at the other end of the first permeated water collecting pipe and the opening at the other end of the second permeated water collecting pipe are both sealed by a sealing means. Of two reverse osmosis membrane element samples simultaneously There is provided a performance evaluation apparatus of the reverse osmosis membrane element that ability evaluation. Further, in the present invention (2), the sealing means includes a shielding portion for blocking the flow of the permeated water flowing through the first and second permeated water collecting pipes from each other. The reverse osmosis membrane element that is coupled by a coupling means provided, or that is formed by sealing both ends of the other ends of the first permeated water collecting pipe and the second permeated water collecting pipe with end caps, respectively. A performance evaluation apparatus is provided. Further, the present invention (3) provides the performance evaluation apparatus for the reverse osmosis membrane element, wherein an intermediate non-permeate water outlet through which the non-permeate water of the first reverse osmosis membrane element specimen flows out is provided at the center of the housing. To do. Moreover, this invention (4) provides the performance evaluation apparatus of the said reverse osmosis membrane element whose said 1st reverse osmosis membrane element specimen and the said 2nd reverse osmosis membrane element specimen are both used reverse osmosis membrane elements. It is.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
A device for evaluating the performance of a reverse osmosis membrane element according to an embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a longitudinal sectional view showing the structure of a reverse osmosis membrane element performance evaluation apparatus according to this embodiment, and FIG. 2 shows an example of a joining state between an end plate of a housing and a permeate water collecting pipe of a reverse osmosis membrane element. FIG. In FIG. 1, a reverse osmosis membrane element performance evaluation apparatus 10 has two reverse osmosis

membrane element specimens

15a and 15b loaded in series in a housing 16, and the two permeate

water collecting pipes

19a and 19b are circulated. The first reverse osmosis membrane element specimen 15a is supplied with the first permeated water, and the second reverse osmosis membrane element specimen is bonded by the sealing means 30 so as to be blocked. The second permeated water is obtained separately from 15b.
[0012]
That is, the reverse osmosis membrane element performance evaluation apparatus 10 has a sample liquid inlet 21 connected to a sample liquid pipe (not shown) and a first permeate outlet 23 connected to the first permeate pipe 22 on one end side. The housing 16 has a non-permeate water outlet 24 connected to a non-permeate water pipe (not shown) and a second permeate outlet 26 connected to the second permeate pipe 25 on the other end side, and an opening at one end loaded in the housing 16. A first reverse osmosis membrane element specimen 15a having a first permeate water collecting pipe 19a connected to the first permeate outlet 23 by an adapter 27, and a first reverse osmosis membrane element specimen 15a loaded in the housing 16 and in series. From the second reverse osmosis membrane element specimen 15b having the second permeate water collecting pipe 19b which is disposed and the opening 32a at one end is connected to the second permeate outlet 26 and the adapter 28. The opening 31b at the other end of the first permeated water collecting pipe 19a and the opening 32b at the other end of the second permeated water collecting pipe 19b are both sealed by the sealing means 30, and two reverses with one analyte liquid. The osmotic

membrane element specimens

15a and 15b are simultaneously evaluated. In addition, an intermediate non-permeate water outlet 33 through which non-permeate water from the first reverse osmosis membrane element specimen 15a installed as needed flows out at the center of the housing 16. As shown in FIGS. 1 and 2, both side members on one end side and the other end side of the housing 16 are usually end plates 20 made of a member different from the cylindrical member of the main body, and the end plate 20 on one end side. Has through holes that serve as the first permeate outlet 23 and the analyte liquid inlet 21. The first permeate outlet 23 formed in the end plate 20 and the permeate water collecting pipe of the reverse osmosis membrane element are joined together with a small-diameter portion 271 in which an O-ring 273 is fitted in an O-ring groove on the outer peripheral surface, This is performed using an adapter 27 including a large-diameter portion 272 in which an O-ring 274 is fitted in the O-ring groove of the surface. The outer diameter of the small diameter portion 271 of the adapter 27 is slightly smaller than the inner diameter of the first permeate outlet 23, and the inner diameter of the large diameter portion 272 of the adapter 27 is slightly larger than the outer diameter of the first permeate water collecting pipe 19a of the reverse osmosis membrane element. The fitting of the first permeate outlet 23 and the small diameter part 271 of the adapter 27 and the fitting of the tip 191a of the first permeate water collecting pipe 19a and the large diameter part 272 of the adapter 27 are ensured by an O-ring. Fixed to.
[0013]
The sealing means 30 is not particularly limited as long as it seals the opening 31b at the other end of the first permeated water collecting pipe and the opening 32b at the other end of the second permeated water collecting pipe. The first permeated water collecting pipe 19a and the second permeated water collecting pipe 19b are coupled by a coupling means 34 including a shielding portion 35 that blocks the mutual flow of permeated water flowing through the two water collecting pipes, Or what sealed both the opening of the other end of the 1st permeated water collection pipe 19a and the 2nd permeated water collection pipe 19b with an end cap, etc. are mentioned, for example. The coupling means 34 of this example is a cylindrical body having the shielding part 35 as an inner wall, and O-rings that fit into O-ring grooves (not shown in the figure) are provided on the inner peripheral surfaces of the left and right sides defined by the shielding part 35. The first permeated water collecting pipe 19a, the second permeated water collecting pipe 19b, and the coupling means 34 are connected to the other end 31b of the first permeated water collecting pipe 19a and the second permeated water collecting pipe 19b from the openings on both sides of the cylindrical body. The other end 32b is pressed into the O-ring against the friction of the O-ring.
[0014]
Further, in the sealing means 30, when both ends of the other ends 31b and 32b of both water collecting pipes are sealed with end caps, the end portions of the end caps after sealing are brought into contact or close to contact. The first reverse osmosis membrane element 15a is prevented from moving along with the close proximity of the sample liquid into the housing 16 by press-fitting. Further, as another example of the sealing means 30, for example, a shield part is made of a metal or resin sheet plate, which is sandwiched between a pair of joining members having a flange part and fixed with screws. You can also. In this case, the connection between the joining member and the other ends 31b and 32b of the two water collecting pipes can be performed by an O-ring method as in this example. Thus, the sealing means 30 in the present invention is in any form such as a split type such as an end cap, an integral type such as a cylindrical body having an inner wall in this example, or a connection type in which a sheet plate is sandwiched between flanges. May be.
[0015]
The first reverse osmosis membrane element specimen 15a and the second reverse osmosis membrane element specimen 15b used in the performance evaluation apparatus 10 of the present invention are not particularly limited, but for example, ultrapure for cleaning electronic component members such as semiconductor devices. A reverse osmosis membrane element of a reverse osmosis membrane module used in the process of producing water, and in a series of processes from recovery of the used reverse osmosis membrane element, regeneration treatment, and supply of a regenerated treatment product It is an evaluation object in the required performance evaluation test. Specifically, the first reverse osmosis membrane element specimen 15a and the second reverse osmosis membrane element specimen 15b are reverse osmosis membrane elements collected after being used or reverse osmosis membrane elements after regeneration treatment. The performance evaluation of the reverse osmosis membrane element that has been used and collected is performed in order to examine the performance of the collected reverse osmosis membrane element in advance and to determine the regenerative treatment conditions according to the results. The performance evaluation of the reverse osmosis membrane element after the treatment is performed in order to grasp the regenerative state of the regenerated product and determine a new supply destination.
[0016]
Used means that the reverse osmosis membrane element is used for a long period of time, the reverse osmosis membrane is contaminated with various inorganic or organic substances, or microorganisms are generated on the wetted part or membrane surface of the raw water in the module. The pressure has increased, the amount of permeated water has decreased, or the membrane has deteriorated, resulting in a decrease in performance such as a slight decrease in its desalination rate. It has been taken out of the module in anticipation of safety because the predetermined period has passed or the accumulated amount of treated water has reached the specified value and performance degradation is expected after several months. Further, the first reverse osmosis membrane element specimen 15a and the second reverse osmosis membrane element specimen 15b may have the same usage history or different usage histories.
[0017]
Since the first reverse osmosis membrane element specimen 15a and the second reverse osmosis membrane element specimen 15b are obtained by collecting used spiral reverse osmosis membrane elements in this example, the structure of the reverse osmosis membrane element is shown in FIGS. This is the same as shown in FIG. That is, in the first reverse osmosis membrane element specimen 15a in FIG. 1, a bag-like reverse osmosis membrane 11a is spirally wound around the first permeate water collecting pipe 19a, and the upper portion thereof is covered with the exterior body 12 and spirally wound. In order to prevent the attached reverse osmosis membrane 11a from sticking out, telescopic stops 14 having several radial ribs 13 are attached to both ends. These first permeable water collecting pipe 19a, reverse osmosis membrane 11a, exterior body 12, and telescope stopper 14 form one reverse osmosis membrane element. Since the second reverse osmosis membrane element specimen 15b has the same structure as the first reverse osmosis membrane element 15a, its description is omitted. When two reverse osmosis membrane elements are loaded in the housing 16, a gap 17 is formed between the outer periphery of the first and second reverse

osmosis membrane elements

15 a and 15 b and the inner periphery of the handling 16. 17 is closed with a brine seal 18.
[0018]
The assembly of the reverse osmosis membrane element performance evaluation device 10 of this example is performed by inserting each member sequentially from one end of the housing 16. The insertion direction is a direction in which the brine seal 18 is closed. In this example, each member is inserted in the right direction from the opening at the left end of the housing 16 in FIG. That is, the second reverse osmosis membrane element specimen 15b, to which the sealing means 30 is attached in advance, is inserted into the housing 16 in which the right end plate 20 and the adapter 28 are assembled. . Next, the first reverse osmosis membrane element 15 a is inserted and fixed by press-fitting the end of the water collecting pipe into the sealing means 30. Next, the other end 191a of the first permeated water collecting pipe is press-fitted into the adapter 27 assembled in advance to the end plate 20, and the end plate 20 is fixed to the housing 16 to complete the assembly (see FIG. 2).
[0019]
The non-permeation through which the analyte liquid pipe, the first permeate pipe, the second permeate pipe, the non-permeate pipe and the intermediate non-permeate water are connected to each inlet and outlet of the reverse osmosis element performance evaluation apparatus 10 of the present invention. It is preferable to install at least one of a flow meter, a pressure meter, a conductivity meter, and a TOC meter in each pipe of the water pipe because the measurement system using this can be automated and performance evaluation can be speeded up. . In addition, even if there is no said instrument at all, it can also sample the liquid or water which flows out from the said piping or the branch pipe branched from this piping, and can evaluate the said water quality.
[0020]
As the performance evaluation items of the reverse osmosis membrane element performed using the reverse osmosis membrane element performance evaluation apparatus 10 of the present invention, the exclusion performance such as salt exclusion performance and organic matter exclusion performance, and the amount of permeated water under a predetermined measurement condition are measured. And the element differential pressure, which is the differential pressure between the test liquid supply pressure and the analyte liquid supply pressure and the non-permeate water (concentrated water) pressure.
[0021]
The salt rejection performance is a so-called desalting performance, a desalination rate, and a salt rejection rate. A salt solution such as a sodium chloride solution is used as a sample liquid, and the salt rejection performance in the sample liquid is measured. As a measuring method, for example, a method of measuring the ratio of the electric conductivity in the sample liquid to the electric conductivity of the permeated water, 1- (the electric conductivity of the permeated water divided by the electric conductivity of the sample liquid), salts are excluded. The method of measuring a rate and the method of measuring a salt exclusion rate from following Formula (1) are mentioned.

[0022]
Organic matter removal performance is reverse osmosis when the recovered reverse osmosis membrane element is very clean Membrane This is an evaluation item used when it is not desired to contaminate with a salt solution. As a measurement method, in the measurement method described in the salt exclusion performance, salts may be applied instead of organic substances. Examples of the organic solution used as the analyte liquid include isopropyl alcohol solutions, saccharide solutions such as glucose, sucrose, and raffinose. The organic matter concentration is measured with a TOC meter.
[0023]
The fresh water generation performance is measured by measuring the flow rate of permeated water under a predetermined measurement condition and comparing it with the flow rate at the time of a new product. When the surface of the reverse osmosis membrane is contaminated, the resistance when water permeates increases and the amount of permeated water decreases. As the value of the new element, the performance value or catalog value of the new element of the same type as the target collection element can be used.
[0024]
The element differential pressure is a flow path differential pressure when water flows through the analyte liquid, and specifically, a differential pressure between the analyte liquid supply pressure and the non-permeate water (concentrated water) pressure. When the flow path through which the water to be treated and concentrated water flows is blocked, the element differential pressure increases.
[0025]
When performing performance evaluation using the performance evaluation apparatus 10 of the present invention, the supply pressure, salt concentration, and the like of the sample liquid are determined by the pressure type of the reverse osmosis membrane element that is the sample. That is, in the high pressure membrane type reverse osmosis membrane element having an operating pressure of 5.5 MPa, a sample liquid having a sodium chloride concentration of 3% is used, and the medium pressure membrane type reverse osmosis membrane element having an operating pressure of 2 to 4 MPa is provided. In a low pressure type reverse osmosis membrane element of 1 to 2 MPa and an ultra low pressure membrane type reverse osmosis membrane element of an operating pressure of 0.5 to 1 MPa, a sample liquid having a sodium chloride concentration of 500 to 2,000 mg / L is used. The flow rate of concentrated water is 80 liters / minute for 8-inch elements and 20 liters / minute for 4-inch elements.
[0026]
Next, an example of a method for evaluating the performance of a reverse osmosis membrane element specimen using the reverse osmosis membrane element performance evaluation apparatus 10 of this example will be described with reference to FIGS. The performance evaluation apparatus 10 in FIG. 3 has a specimen liquid pipe 51, a first permeate water pipe 22, a second permeate water pipe 25, and a non-permeate water pipe at each inlet and outlet of the reverse osmosis membrane element performance evaluation apparatus 10 in FIG. 53 and an intermediate non-permeate water pipe 55 through which intermediate non-permeate water passes are connected. In these pipes, a flow meter 41, a pressure gauge 42, a conductivity meter 43, and a TOC meter 44 are respectively installed. Yes. In FIG. 3, a pump, a needle valve, a switching valve, and the like that determine the measurement pressure are omitted.
[0027]
In FIG. 1 and FIG. 3, first, a sample liquid is press-fitted from a sample liquid pipe 51 connected to the housing 16 using a pump (not shown). In the figure, as shown by the arrows, the analyte liquid passes between the radial ribs 13 of the telescope stopper 14 and enters the first reverse osmosis membrane element specimen 15a. Specimen The liquid passes between the membranes of the first reverse osmosis membrane element specimen 15a and reaches the next second reverse osmosis membrane element specimen 15b, and the other specimen liquid permeates through the first reverse osmosis membrane 11a to become permeated water. The permeated water is collected in the first permeated water collecting pipe 19a and flows out from the first permeated water pipe 22 as the first permeated water. Next, the analyte liquid that reached the second reverse osmosis membrane element specimen 15b passed through the membrane, and the analyte liquid that did not permeate the reverse osmosis membrane was connected to the housing 16 as non-permeated water (concentrated water). It flows out to the non-permeate water pipe 53. Further, the permeated water that has permeated through the second reverse osmosis membrane 11b of the second reverse osmosis membrane element specimen 15b flows out of the housing 16 from the second permeated water pipe 25 through the second permeated water collecting pipe 19b. On the other hand, the intermediate non-permeated water that passes through between the membranes of the first reverse osmosis membrane element specimen 15a and does not reach the second reverse osmosis membrane element specimen 15b is the analyte liquid of the second reverse osmosis membrane element specimen 15b. It flows out to the intermediate impermeable water pipe 55.
[0028]
According to FIG. 3, the first permeated water collecting pipe 19a of the first reverse osmosis membrane element specimen 15a and the second permeated water collecting pipe 19b of the second reverse osmosis membrane element specimen 15b are both collected by the sealing means 30. Since the flow of the permeate flowing through the water pipe is blocked, the first permeate obtained from the first permeate pipe 22 is not affected by the second permeate collected in the second permeate water collecting pipe 19b. The second permeated water is not affected by the first permeated water collected in the first permeated water collecting pipe 19a. For this reason, for example, the salt rejection performance or organic matter rejection performance of the first reverse osmosis membrane element specimen 15a is obtained by measuring the electrical conductivity or TOC of the sample liquid and the electrical conductivity or TOC of the first permeated water. At the same time, the salt rejection performance or organic matter rejection performance of the second reverse osmosis membrane element specimen 15b is determined by measuring the electrical conductivity or TOC of the intermediate non-permeate water and the electrical conductivity or TOC of the second permeate water. Desired. Further, for example, the water generation performance of the first reverse osmosis membrane element specimen 15a is obtained by measuring the flow rate of the first permeate under predetermined measurement conditions, and at the same time, the second reverse osmosis membrane element specimen 15b is made. Water performance is calculated | required by measuring the flow volume of 2nd permeated water on predetermined | prescribed measurement conditions. Further, for example, the element differential pressure of the first reverse osmosis membrane element specimen 15a is obtained by measuring the supply pressure of the analyte liquid and the pressure of the intermediate non-permeate water, and at the same time, the second reverse osmosis membrane element specimen 15b is measured. The element differential pressure is obtained by measuring the supply pressure of the non-permeate water and the pressure of the non-permeate water. . Na When the intermediate non-permeate outlet 33 is not provided, for example, a value obtained by subtracting the first permeate amount from the flow rate of the sample liquid may be used as the intermediate non-permeate flow rate, and this calculated value may be used as a measurement reference value.
[0029]
The reverse osmosis membrane element whose performance has been evaluated by such a method is sufficiently cleaned by flowing pure water into the housing using the same apparatus as described above, for example, in the case of performance evaluation before regenerative treatment, and then contaminated. Regenerative processing is performed under conditions determined in accordance with the degree of. In the case of performance evaluation after regenerative processing, after reusing pure water, the reusable element to be used is determined as a reuse destination based on the performance evaluation value.
[0030]
The performance evaluation apparatus for reverse osmosis membrane element of the present invention may be arranged in parallel by using two or more of them, and simultaneously evaluate four or more reverse osmosis membrane element samples with one analyte liquid. . Since the performance evaluation apparatus can also be used as a regenerative processing apparatus as described above, the connection between the housing and the sample liquid pipe is connected between the housing and the pure water supply pipe or the chemical liquid supply pipe by, for example, operating the switching valve. If it makes it, it can be set as the performance evaluation apparatus and regeneration apparatus of a reverse osmosis membrane element.
[0031]
Thus, according to the reverse osmosis membrane element performance evaluation apparatus 10 of the present invention, the permeate collection of each other despite the two reverse osmosis membrane element specimens being arranged in series in one housing. Since the water tubes are not common but independent, the individual performance can be evaluated separately with one analyte liquid.
[0032]
【The invention's effect】
According to the present invention, the performance of two reverse osmosis membrane element specimens arranged in series in one housing can be evaluated individually with one specimen liquid at the same time. For this reason, the time required for the performance evaluation of the reverse osmosis membrane element can be shortened. Further, for example, since a used reverse osmosis membrane element recovered from a reverse osmosis membrane module used in a water treatment facility can be efficiently evaluated, regeneration processing and regeneration that are steps after the collection of the used reverse osmosis membrane element are performed. It is possible to quickly supply processed products.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view showing the structure of a performance evaluation apparatus for a reverse osmosis membrane module according to an embodiment of the present invention.
FIG. 2 is a view showing an example of a joined state between an end plate of a housing and a permeate water collecting pipe of a reverse osmosis membrane element.
FIG. 3 is a diagram for explaining a performance evaluation method using the performance evaluation apparatus of FIG. 1;
FIG. 4 is a longitudinal sectional view showing a structure of a conventional reverse osmosis membrane module with a part thereof omitted.
5 is a longitudinal sectional view taken along line AA in FIG. 3. FIG.
[Explanation of symbols]
10 Performance evaluation device for reverse osmosis membrane element
11a, 11b, 81 Reverse osmosis membrane
14,84 Telescope stop
15a First reverse osmosis membrane element specimen
15b Second reverse osmosis membrane element specimen
16, 86 housing
18, 88 brine seal
19a First permeate water collecting pipe
19b Second permeate water collecting pipe
20 End plate
21 Sample fluid inlet
22 First permeate pipe
23 First permeate outlet
24 Non-permeate outlet
25 Second permeate pipe
26 Second permeate outlet
30 Sealing means
41 Flow meter
42 Pressure gauge
43 Conductivity meter
44 TOC meter
51 Sample liquid tube
53 Non-permeate water pipe
55 Middle non-permeate water pipe

Claims

The first permeated water outlet connected to the analyte liquid inlet and the first permeated water pipe connected to the analyte liquid pipe on one end side, and the non-permeated water outlet and the second permeated water connected to the non-permeated water pipe on the other end side. A housing having a second permeate outlet connected to the water pipe;
A first reverse osmosis membrane element specimen having a first permeate water collecting pipe loaded in the housing and having an opening at one end connected to the first permeate outlet, and the first reverse osmosis membrane element specimen loaded in the housing; A second reverse osmosis membrane element specimen having a second permeate water collecting pipe arranged in series and having an opening at one end connected to the second permeate outlet, the opening at the other end of the first permeate water collecting pipe and the The performance of the reverse osmosis membrane element is characterized in that the opening at the other end of the second permeated water collecting pipe is sealed with a sealing means, and the performance of two reverse osmosis membrane element specimens is simultaneously evaluated with one specimen liquid. Evaluation device.

The sealing means is a combination of the first permeated water collecting pipe and the second permeated water collecting pipe with a coupling means including a shielding portion for blocking the flow of permeated water flowing through the two water collecting pipes. 2. The reverse osmosis membrane element according to claim 1, wherein both openings at the other ends of the first permeate water collecting pipe and the second permeate water collecting pipe are sealed with end caps, respectively. Performance evaluation device.

The performance evaluation apparatus for a reverse osmosis membrane element according to claim 1 or 2, wherein an intermediate non-permeate water outlet through which the non-permeate water of the first reverse osmosis membrane element specimen flows out is provided at a central portion of the housing. .

4. The reverse osmosis membrane element according to claim 1, wherein the first reverse osmosis membrane element specimen and the second reverse osmosis membrane element specimen are both used reverse osmosis membrane elements. 5. Performance evaluation device.