Nothing Special   »   [go: up one dir, main page]

JP3632331B2 - Ion exchange method and ion exchange column used in this ion exchange method - Google Patents

Ion exchange method and ion exchange column used in this ion exchange method Download PDF

Info

Publication number
JP3632331B2
JP3632331B2 JP31150396A JP31150396A JP3632331B2 JP 3632331 B2 JP3632331 B2 JP 3632331B2 JP 31150396 A JP31150396 A JP 31150396A JP 31150396 A JP31150396 A JP 31150396A JP 3632331 B2 JP3632331 B2 JP 3632331B2
Authority
JP
Japan
Prior art keywords
exchange resin
ion exchange
water
layer
regenerant
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
JP31150396A
Other languages
Japanese (ja)
Other versions
JPH10137751A (en
Inventor
円 田辺
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Organo Corp
Original Assignee
Organo Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Family has litigation
First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=18018026&utm_source=google_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=JP3632331(B2) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Application filed by Organo Corp filed Critical Organo Corp
Priority to JP31150396A priority Critical patent/JP3632331B2/en
Publication of JPH10137751A publication Critical patent/JPH10137751A/en
Application granted granted Critical
Publication of JP3632331B2 publication Critical patent/JP3632331B2/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Landscapes

  • Separation Using Semi-Permeable Membranes (AREA)
  • Treatment Of Water By Ion Exchange (AREA)

Description

【０００１】
【発明の属する技術分野】
本発明は、イオン交換方法及びこのイオン交換方法に用いられるイオン交換塔に関し、更に詳しくは、例えばボイラ給水や電子部品等の洗浄用水等に使用される純水を製造する際に好適に用いられるイオン交換方法及びこのイオン交換方法に用いられるイオン交換塔に関する。
【０００２】
【従来の技術】
従来のイオン交換方法及びイオン交換塔として代表的なものとして例えば２床３塔式イオン交換装置や混床式イオン交換装置等がある。２床３塔式イオン交換装置は、例えば強酸性カチオン交換樹脂が充填されたカチオン交換塔と、強塩基性アニオン交換樹脂が充填されたアニオン交換塔と、これら両者の間に配置された脱炭酸塔とを備え、例えば原水の下降流通水によりカチオン交換塔において原水中のカルシウムイオン、マグネシウムイオン、ナトリウムイオン等のカチオンを強酸性カチオン交換樹脂の水素イオンとイオン交換した後、脱炭酸塔内において酸性下で炭酸イオンを炭酸ガスとして脱炭酸し、次いでアニオン交換塔における下降流通水により原水中の硫酸イオン、塩素イオン等のアニオンやシリカを強塩基性アニオン交換樹脂の水酸化物イオンとイオン交換して純水を製造するようにしている。そして、上記各イオン交換樹脂の再生を行う場合には、例えば各イオン交換塔にそれぞれの再生剤を下降流で通液して並流再生を行い、あるいはそれぞれの再生剤を上昇流で通液して向流再生を行うようにしている。
【０００３】
一方、混床式イオン交換装置は、強酸性カチオン交換樹脂と強塩基性アニオン交換樹脂とが混合された混合イオン交換樹脂層からなる充填層を有するイオン交換塔を備え、例えば原水の下降流通水によりイオン交換塔において原水中のカチオン及びアニオンを高効率で同時にイオン交換して純度の高い純水を製造するようにしている。そして、各イオン交換樹脂の再生を行う時には同一塔内で、混合イオン交換樹脂層を逆洗分離し、各イオン交換樹脂の比重差により上層に強塩基性アニオン交換樹脂層を、下層に強酸性カチオン交換樹脂層を形成した後、各イオン交換樹脂層にそれぞれの再生剤を通液して両イオン交換樹脂を個別に再生するようにしている。この再生操作は同一塔内で行われることもあるし、各イオン交換樹脂を別の塔に個別に抜き出し、それぞれの塔内で個別に再生を行うこともある。
【０００４】
【発明が解決しようとする課題】
しかしながら、従来の２床３塔式イオン交換装置の場合には、塔構成がカチオン塔、脱炭酸塔及びアニオン塔の３塔構成であるため、装置としては大型化して設置面積が大きくなり、コスト的にも高くなるという課題があった。一方、混床式イオン交換装置の場合には、イオン交換塔としては一塔で済み装置自体としては小型化することができるが、強酸性カチオン交換樹脂と強塩基性アニオン交換樹脂とが混合しているため、両イオン交換樹脂が互いに付着して混合樹脂塊を作る、いわゆるクランピング現象が発生することがある。この混合樹脂塊は再生時の逆洗分離操作では完全に分離させることが難しく、逆洗分離操作による分離後の強酸性カチオン交換樹脂層と強塩基性アニオン交換樹脂層の双方に混合樹脂塊が混じるため、再生操作を行っても各層に存在する混合樹脂塊が再生不良となり、あるいは混合樹脂塊がそれぞれの層内で逆再生を受ける。この状態のまま混合操作を行うと、例えばナトリウム形に逆再生された強酸性カチオン交換樹脂はナトリウムを、塩素イオン形に逆再生された強塩基性アニオン交換樹脂は塩化物イオン形をそれぞれ放出するが、塔出口付近で放出されたこれらの不純物は除去されず、処理水の純度を低下させてしまう。また、このようなクランピング現象がない場合であっても、再生通液時における出口側に位置するイオン交換樹脂層は僅かながら不純物イオンが残留する傾向となり、この不純物イオン形のイオン交換樹脂は、通水前の混合操作によって層内に均一に分布することになるので、通水時に不純物イオンを放出し、処理水の純度を低下させてしまう。例えば、シリカは再生後樹脂粒内に残留し易い不純物であり、通水前に混合操作を行う混床式の装置では１〜５ｐｐｂ程度のシリカリークが避けられなかった。また、混床式の場合には再生工程で逆洗分離操作をイオン交換塔内で行うため、塔高として充填層の高さの２倍程度の塔高が必要となり、装置的に必ずしも小型化することができないという課題があった。まして、再生操作を別塔で行う場合には再生塔が別途必要となり、装置の大型化を免れない。
【０００５】
混合イオン交換樹脂のクランピングを防止したイオン交換装置として、例えば強酸性カチオン交換樹脂層上に強塩基性アニオン交換樹脂層を積層し、下降流通水を行う複層式イオン交換装置もあるが、この装置の場合には例えば上層の強塩基性アニオン交換樹脂層を下降流通液により再生し、下層の強酸性カチオン交換樹脂層を上昇流通液により再生するため、上層の流出側（強塩基性アニオン交換樹脂の下層部）にシリカ等の不純物イオンが残り、あるいは両イオン交換樹脂層の界面近傍で相互の再生剤による逆再生部分を生じ、十分な純度が得られないという課題があった。更に、この複層式イオン交換装置の場合には原水がまず強塩基性アニオン交換樹脂層と接触するため、硬度成分の多い原水に適用すると、通水時に強塩基性アニオン交換樹脂層において水酸化マグネシウム等の難溶性物質を生成するため、前段に軟水器を設置しなくてはならず、装置的に大型化するという課題があった。
【０００６】
本発明は、上記課題を解決するためになされたもので、イオン交換装置をコンパクト化することができ、またクランピングによる再生不良がなく、ひいてはシリカリーク等の不純物イオンのリークがなく、高純度の水を製造することができるイオン交換方法及びこのイオン交換方法に用いられるイオン交換塔を提供することを目的としている。
【０００７】
【課題を解決するための手段】
本発明の請求項１に記載のイオン交換方法は、同一塔内に形成された強酸性カチオン交換樹脂層と強塩基性アニオン交換樹脂層の各層に被処理水を通水する通水工程と、上記各イオン交換樹脂層にそれぞれの再生剤を通液する操作を含む再生工程とを有し、上記通水工程と上記再生工程を交互に行うイオン交換方法であって、上記通水工程では両イオン交換樹脂の積層状態を維持したまま被処理水を両イオン交換樹脂層の一方のイオン交換樹脂層に通水した後、他方のイオン交換樹脂層に通水し、上記再生工程では、上記両イオン交換樹脂の逆洗操作を行うことなく、上記各イオン交換樹脂層に上記被処理水の通水方向とは逆の方向にそれぞれの再生剤を通液すると共に上記両イオン交換樹脂に被処理水を通水する順序と逆の順序で上記両イオン交換樹脂を再生することを特徴とするものである。
【０００９】
また、本発明の請求項２に記載のイオン交換方法は、同一塔内で上層として形成された強酸性カチオン交換樹脂層と下層として形成された強塩基性アニオン交換樹脂層に被処理水を上層から下層へ下降流で通水する通水工程と、上記各イオン交換樹脂層にそれぞれの再生剤を上昇流で通液する操作を含む再生工程とを有し、上記通水工程と上記再生工程を交互に行うイオン交換方法であって、上記通水工程終了後の上記再生工程では、上記両イオン交換樹脂の逆洗操作を行うことなく、先に下層の強塩基性アニオン交換樹脂にその再生剤を通液し、その後に上層の強酸性カチオン交換樹脂にその再生剤を通液することを特徴とするものである。
【００１０】
また、本発明の請求項３に記載のイオン交換方法は、同一塔内で上層として形成された強酸性カチオン交換樹脂層と下層として形成された強塩基性アニオン交換樹脂層に被処理水を下層から上層へ上昇流で通水する通水工程と、上記各イオン交換樹脂層にそれぞれの再生剤を下降流で通液する操作を含む再生工程とを有し、上記通水工程と上記再生工程を交互に行うイオン交換方法であって、上記通水工程終了後の上記再生工程では、上記両イオン交換樹脂の逆洗操作を行うことなく、先に上層の強酸性カチオン交換樹脂にその再生剤を通液し、その後に下層の強塩基性アニオン交換樹脂にその再生剤を通液することを特徴とするものである。
【００１１】
また、本発明の請求項４に記載のイオン交換方法は、同一塔内で上層として形成された強塩基性アニオン交換樹脂層と下層として形成された強酸性カチオン交換樹脂層に被処理水を上層から下層へ下降流で通水する通水工程と、上記各イオン交換樹脂層にそれぞれの再生剤を上昇流で通液する操作を含む再生工程とを有し、上記通水工程と上記再生工程を交互に行うイオン交換方法であって、上記通水工程終了後の上記再生工程では、上記両イオン交換樹脂層の逆洗操作を行うことなく、先に下層の強酸性カチオン交換樹脂にその再生剤を通液し、その後に上層の強塩基性アニオン交換樹脂層にその再生剤を通液することを特徴とするものである。
【００１２】
また、本発明の請求項５に記載のイオン交換方法は、同一塔内で上層として形成された強塩基性アニオン交換樹脂層と下層として形成された強酸性カチオン交換樹脂層に被処理水を下層から上層へ上昇流で通水する通水工程と、上記各両イオン交換樹脂層にそれぞれの再生剤を下降流で通液する操作を含む再生工程とを有し、上記通水工程と上記再生工程を交互に行うイオン交換方法であって、上記通水工程終了後の上記再生工程では、両イオン交換樹脂層の逆洗操作を行うことなく、先に上層の強塩基性アニオン交換樹脂にその再生剤を通液し、その後に下層の強酸性カチオン交換樹脂にその再生剤を通液することを特徴とするものである。
【００１３】
また、本発明の請求項６に記載のイオン交換方法は、請求項１〜請求項５のいずれか１項に記載の発明において、上記被処理水として予め逆浸透膜装置により処理した透過水を用いることを特徴とするものである。
【００１４】
また、本発明の請求項７に記載のイオン交換塔は、同一塔内で上層として形成された強酸性カチオン交換樹脂層と下層として形成された強塩基性アニオン交換樹脂層に被処理水を上層から下層へ下降流で通水する通水工程と、上記各イオン交換樹脂層にそれぞれの再生剤を上昇流で通液する操作を含む再生工程とを有し、上記通水工程と上記再生工程を交互に行う際に、上記通水工程終了後の上記再生工程では、上記両イオン交換樹脂の逆洗操作を行うことなく、先に下層の強塩基性アニオン交換樹脂にその再生剤を通液し、その後に上層の強酸性カチオン交換樹脂にその再生剤を通液する下降流通水、上昇流再生によるイオン交換方法に用いられるイオン交換塔であって、上層の強酸性カチオン交換樹脂層と下層の強塩基性アニオン交換樹脂層を仕切る仕切板を塔内に横方向に設けると共に上記仕切板の下方近傍に再生剤の出入管を設け、且つ、上記仕切板は被処理水の流通を許すが、上記各イオン交換樹脂の流通を阻止するように構成されたことを特徴とするものである。
【００１５】
また、本発明の請求項８に記載のイオン交換塔は、同一塔内で上層として形成された強酸性カチオン交換樹脂層と下層として形成された強塩基性アニオン交換樹脂層に被処理水を下層から上層へ上昇流で通水する通水工程と、上記各イオン交換樹脂層にそれぞれの再生剤を下降流で通液する操作を含む再生工程とを有し、上記通水工程と上記再生工程を交互に行う際に、上記通水工程終了後の上記再生工程では、上記両イオン交換樹脂の逆洗操作を行うことなく、先に上層の強酸性カチオン交換樹脂にその再生剤を通液し、その後に下層の強塩基性アニオン交換樹脂にその再生剤を通液する、上昇流通水、下降流再生によるイオン交換方法に用いられるイオン交換塔であって、上層の強酸性カチオン交換樹脂層と下層の強塩基性アニオン交換樹脂層を仕切る仕切板を塔内に横方向に設けると共に上記仕切板の上方近傍に再生剤の出入管を設け、且つ、上記仕切板は被処理水の流通を許すが、上記各イオン交換樹脂の流通を阻止するように構成されたことを特徴とするものである。
【００１６】
また、本発明の請求項９に記載のイオン交換塔は、同一塔内で上層として形成された強塩基性アニオン交換樹脂層と下層として形成された強酸性カチオン交換樹脂層に被処理水を上層から下層へ下降流で通水する通水工程と、上記各イオン交換樹脂層にそれぞれの再生剤を上昇流で通液する操作を含む再生工程とを有し、上記通水工程と上記再生工程を交互に行う際に、上記通水工程終了後の上記再生工程では、上記両イオン交換樹脂層の逆洗操作を行うことなく、先に下層の強酸性カチオン交換樹脂にその再生剤を通液し、その後に上層の強塩基性アニオン交換樹脂層にその再生剤を通液する下降流通水、上昇流再生によるイオン交換方法に用いられるイオン交換塔であって、上層の強塩基性アニオン交換樹脂層と下層の強酸性カチオン交換樹脂層を被処理水の流通を許すが、上記各イオン交換樹脂の流通を阻止する仕切板により仕切り、あるいは仕切板により仕切ることなく、更に上記両イオン交換樹脂層の分離境界面または上記仕切板の下方近傍に再生剤の出入管を設けたことを特徴とするものである。
【００１７】
また、本発明の請求項１０に記載のイオン交換塔は、同一塔内で上層として形成された強塩基性アニオン交換樹脂層と下層として形成された強酸性カチオン交換樹脂層に被処理水を下層から上層へ上昇流で通水する通水工程と、上記各両イオン交換樹脂層にそれぞれの再生剤を下降流で通液する操作を含む再生工程とを有し、上記通水工程と上記再生工程を交互に行う際に、上記通水工程終了後の上記再生工程では、両イオン交換樹脂層の逆洗操作を行うことなく、先に上層の強塩基性アニオン交換樹脂にその再生剤を通液し、その後に下層の強酸性カチオン交換樹脂にその再生剤を通液する上昇流通水、下降流再生によるイオン交換方法に用いられるイオン交換塔であって、上層の強塩基性アニオン交換樹脂層と下層の強酸性カチオン交換樹脂層を被処理水の流通を許すが、上記各イオン交換樹脂の流通を阻止する仕切板により仕切り、あるいは仕切板により仕切ることなく、更に上記両イオン交換樹脂層の分離境界面または上記仕切板の上方近傍に再生剤の出入管を設けたことを特徴とするものである。
【００１８】
また、本発明の請求項１１に記載のイオン交換塔は、同一塔内に形成された強酸性カチオン交換樹脂層と強塩基性アニオン交換樹脂層の各層に被処理水を通水する通水工程と、上記各イオン交換樹脂層にそれぞれの再生剤を通液する操作を含む再生工程とを有し、上記通水工程と上記再生工程を交互に行う際に、上記通水工程では両イオン交換樹脂の積層状態を維持したまま被処理水を両イオン交換樹脂層の一方のイオン交換樹脂層に通水した後、他方のイオン交換樹脂層に通水し、上記再生工程では、上記両イオン交換樹脂の逆洗操作を行うことなく、上記各イオン交換樹脂層に上記被処理水の通水方向とは逆の方向にそれぞれの再生剤を通液すると共に上記両イオン交換樹脂に被処理水を通水する順序と逆の順序で上記両イオン交換樹脂を再生するイオン交換方法に用いられるイオン交換塔であって、強酸性カチオン交換樹脂層と強塩基性アニオン交換樹脂層とを仕切る上下２段の仕切板を空間を介して塔内に横方向にそれぞれ設けると共に上記両仕切板間の空間に上記各再生剤の出入管を設け、これら両仕切板は被処理水の流通を許すが、上記各イオン交換樹脂の流通を阻止するように構成されたことを特徴とするものである。
【００１９】
【発明の実施の形態】
以下、図１〜図１１に示す実施形態に基づいて本発明を説明する。尚、各図中、図１〜図１０はぞれぞれ本発明のイオン交換方法に用いられるイオン交換塔の実施形態を示す概念図で、図１１は図１に示すイオン交換塔を適用した純水製造装置の要部を示すフロー図である。
【００２０】
図１に示すイオン交換塔１０は、塔本体１１と、この塔本体１１内に強酸性カチオン交換樹脂により形成された上層１２と、上記塔本体１１内に強塩基性アニオン交換樹脂により形成された下層１３と、これらの上下層１２、１３を塔本体１１の高さ方向の中程で横方向に仕切るように塔本体１１内に設けられた仕切板１４と、この仕切板１４の下方近傍にこれと平行に設けられた出入管１５とを備え、下降流通水、上昇流再生を行うように構成されている。そして、上層１２の強酸性カチオン交換樹脂は仕切板１４によって支持され、下層１３の強塩基性アニオン交換樹脂は塔本体１１内の下部に仕切板１４と平行に設けられた第２仕切板１６によって支持されている。従って、上層１２の強酸性カチオン交換樹脂は仕切板１４によって下層１３から区画されているため、上層１２の強酸性カチオン交換樹脂が下層１３の強塩基性アニオン交換樹脂と混合することはない。また、下層１３の強塩基性アニオン交換樹脂の上面と仕切板１４との間には再生時に膨潤する量に見合う僅かな隙間が形成され、この隙間に出入管１５が配置されている。また、塔本体１１内の上部には第３仕切板１７が仕切板１４と平行に設けられ、第３仕切板１７と強酸性カチオン交換樹脂層１２の上面に強塩基性アニオン交換樹脂の場合と同様に再生時に膨潤する量に見合う僅かな隙間が形成されている。本発明において各仕切板の下方に形成する隙間は、上述のように再生時に膨潤する量に見合った僅かな隙間のことであり、後述する各実施形態における隙間の意味も同様である。
【００２１】
また、上記各仕切板１４、１６、１７はいずれも上下の空間を連通する多数の連通手段が全面に均等に分散して形成され、これらの連通手段は被処理水や再生剤が流通し、各イオン交換樹脂が流通できないように構成されている。そして、上記塔本体１１の塔頂には被処理水としての原水が流入する流入管１１Ａが接続され、塔底には処理水が流出する流出管１１Ｂが接続され、流入管１１Ａから塔本体１１内へ流入する原水は上層１２の強酸性カチオン交換樹脂層、下層１３の強塩基性アニオン交換樹脂層を順次通水する間にイオン交換され、不純物イオンが除去された処理水として流出管１１Ｂから流出するようにしてある。尚、図１では原水及び処理水に関連する配管及び原水及び処理水の流れは実線で示してある。後述する他の実施形態のイオン交換塔を示す図２〜図１０においても同様である。
【００２２】
また、上記塔本体１１の塔頂の流入管１１Ａには上層１２の強酸性カチオン交換樹脂の酸再生廃液が流出する第２流出管１１Ｃが接続されており、塔底の流出管１１Ｂにはアルカリ再生剤が流入する第２流入管１１Ｄが接続している。更に、塔本体１１内の出入管１５には外部配管１５Ａが接続され、この外部配管１５Ａから酸再生剤が流入し、出入管１５を介して上層１２の強酸性カチオン交換樹脂層１２全体に分散供給され、また、この出入管１５を介して下層の強塩基性アニオン交換樹脂層１３からのアルカリ再生廃液が外部配管１５Ａから排出するようにしてある。尚、図１では再生剤に関連する配管及び再生剤の流れは一点鎖線で示してある。後述する他の実施形態のイオン交換塔を示す図２〜図１０においても同様である。
【００２３】
従って、再生時には、アルカリ再生剤は塔底の第２流入管１１Ｄから塔本体１１の底部空間に流入し、第２仕切板１６を介して下層１３の強塩基性アニオン交換樹脂の下面全体に分散されて下層１３を上昇流で通液し、アルカリ再生廃液が出入管１５を経由して外部配管１５Ａから排出される。また、酸再生剤は外部配管１５Ａから供給され、出入管１５を介して下層１３と仕切板１４間の隙間に流入し、仕切板１４を介して上層１２の強酸性カチオン交換樹脂の下面全体に分散されて上層１２を上昇流で通液し、酸再生廃液が第３仕切板１７を経由して第２流出管１１Ｃから排出される。つまり、各イオン交換樹脂の再生時にはそれぞれの再生剤を原水の通水方向とは逆向きに通液し、向流再生方式により各イオン交換樹脂を再生する。この際、一方のイオン交換樹脂層を再生する時には他方のイオン交換樹脂層に純水をバランス水として連続的に通水し、一方の再生剤が他方のイオン交換樹脂層に流入しないようにしている。バランス水を供給する時には例えば原水の流入管１１Ａ及び流出管１１Ｂを利用することができる。
【００２４】
再生順序としては、通水出口側に位置する下層１３の強塩基性アニオン交換樹脂を先に再生し、後で通水入口側に位置する上層１２の強酸性カチオン交換樹脂を再生するようにしてある。このように通水出口側である下層１３の強塩基性アニオン交換樹脂を先に向流再生することにより、高純度の処理水を得ることができる。例えば、先に上層１２の強酸性カチオン交換樹脂を再生し、後に下層１３の強塩基性アニオン交換樹脂再生すると、折角、上昇流再生によって高度に再生された強酸性カチオン交換樹脂層の下層部に、後に再生する強塩基性アニオン交換樹脂の再生剤である水酸化ナトリウム水溶液等のアルカリ再生剤が接触し、処理水の導電率に最も影響を与える強酸性カチオン交換樹脂層の下層部が塩形となってしまい処理水の純度を低下させてしまう。一方、下層１３の強塩基性アニオン交換樹脂を再生し、後に上層１２の強酸性カチオン交換樹脂を再生した場合には、上述したような現象が生ずることなく、高純度の処理水を得ることができる。尚、先に下層１３を再生し、後に上層１２を再生すると、再生済みの強塩基性アニオン交換樹脂層の上層部に、上層１２の再生剤である塩酸等の酸再生剤が接触して塩形となるが、この場合は被処理水（酸性軟水）が最初に接触する部分であるから処理水の純度低下に対して影響を与えることがない。即ち、下層１３を形成する強塩基性アニオン交換樹脂層は、図１においては上昇流で再生するため、処理水の塩化物イオンやシリカリークに最も影響を与える最下層部は理想的に再生されていることによる。
【００２５】
尚、図１において、出入管１５を仕切板１４の下方近傍に設置するのは次の理由による。前述のように図１に示した実施形態では上層（強酸性カチオン交換樹脂層）１２を再生する際、その再生後において上層１２に塩形の強酸性カチオン交換樹脂が残留していると、処理水の純度が低下する。よって、仕切板１４の下方に出入管１５を設置し、ここから再生剤を流入させることにより仕切板１４の上方に位置する強酸性カチオン交換樹脂の全てに均等に再生剤を接触させ、未再生の部分を極力なくすることができる。例えば、出入管１５を仕切板１４の上方に設置した場合には、再生剤に接触しない部分が生じ、処理水の純度を低下させる原因になる。後述する他の実施形態においても、出入管の設置位置に関しては上述したように処理水の純度に影響を与える未再生のイオン交換樹脂が生じないような位置に設置するように配慮されている。
【００２６】
次に、上記イオン交換塔１０を用いた本発明のイオン交換方法について説明する。通水工程で原水を処理する時には、原水が流入管１１Ａから塔本体１１内へ流入し、第３仕切板１７を介して強酸性カチオン交換樹脂からなる上層１２の上面全面に分散する。この原水は上層１２全体を下降流により通水し、この間に原水中のカルシウムイオン、マグネシウムイオン、ナトリウムイオン等のカチオンが強酸性カチオン交換樹脂により除去される。その後、原水は仕切板１４を介して強塩基性アニオン交換樹脂からなる下層１３上面全面に分散し、下層１３を通水する間に、原水中の硫酸イオンや塩素イオン等のアニオンやシリカが強塩基性アニオン交換樹脂により除去され、アニオン及びカチオンが除去された高純度の処理水として第２仕切板１６を経由し、流出管１１Ｂから流出し、次工程へ供給される。
【００２７】
原水の処理により各イオン交換樹脂が貫流点に達したら再生工程で各イオン交換樹脂を再生する。それには各イオン交換樹脂層を逆洗することなく、まず、通水出口側に位置する下層１３の強塩基性アニオン交換樹脂を向流再生する。即ち、アルカリ再生剤として例えば水酸化ナトリウム水溶液を塔底の第２流入管１１Ｄから上昇流で供給すると共に、バランス水を塔頂部から下降流で塔本体１１内へ供給する。これによりアルカリ再生剤は塔底の空間に流入し、第２仕切板１６を介して下層１３全体へ上昇流で通液される。この時、下層１３はアルカリ再生剤の供給圧によりイオン交換樹脂層全体がピストン移動して仕切板１４に押し付けられ、この状態で通液し続けると、強塩基性アニオン交換樹脂はアルカリ再生剤により効率良く再生され、この時のアルカリ再生廃液は上記バランス水と共に出入管１５を経由して外部配管１５Ａから排出される。下層１３の強塩基性アニオン交換樹脂の向流再生を行った後、アルカリ再生剤に代えて純水を塔底から供給し、塔本体１１の塔頂、塔底の双方から通水して下層１３の強塩基性アニオン交換樹脂の再生剤の押出し及び洗浄操作を行い、洗浄廃液は出入管１５、外部配管１５Ａを介して排出される。
【００２８】
下層の洗浄操作の後、通水入口側に位置する上層１２の強酸性カチオン交換樹脂を向流再生する。即ち、下層１３にバランス水を供給すると共に、外部配管１５Ａから酸再生剤を供給する。これにより酸再生剤は出入管１５を介して仕切板１４の下側の隙間に流入し、ここでバランス水と合流し、仕切板１４を介して強酸性カチオン交換樹脂からなる上層１２全体へ上昇流で通液される。この通液に伴って上層１２はイオン交換樹脂層全体がピストン移動して第３仕切板１７に押し付けられる。この状態で酸再生剤を通液し続けると、強酸性カチオン交換樹脂は酸再生剤により効率良く再生され、この時の酸再生廃液は第２流出管１１Ｃから排出される。上層１２の強酸性カチオン交換樹脂の向流再生後、酸再生剤の供給を停止し、塔底のみから純水を上昇流通水して上層１２の強酸性カチオン交換樹脂の再生剤の押出し及び洗浄操作を行い、洗浄廃液は塔頂から排出される。後は、通水工程と再生工程とを逆洗操作を行うことなく繰り返してイオン交換反応により原水を処理して純水を製造する。
【００２９】
本発明では通水終了後の両イオン交換樹脂層の逆洗操作を行うことなく、両イオン交換樹脂層に被処理水を通水する方向とは逆方向にそれぞれの再生剤を通液する、いわゆる向流再生を行うため、通水終了時にイオン交換樹脂層で形成されたイオン形の配列を乱すことなく、そのまま再生することができ、通水終了時に残留している最下層の再生形のイオン交換樹脂を有効に活用することができると共に再生効率を最大限とすることができる。例えば、図１において上層１２の強酸性カチオン交換樹脂の場合について更に説明すると、通水時のこの樹脂層の配列は、上からカルシウム形、ナトリウム形、水素形になっているが、この樹脂層を逆洗することなく、このままの状態で酸再生剤として塩酸を樹脂層の下側から通液すると、塩酸は下層部の水素形の樹脂を素通りしてまずナトリウム形の樹脂を溶離してこれを水素形とし、その廃液である塩化ナトリウムが更に上層のカルシウム形の樹脂を溶離してこれをナトリウム形とし、更にまたそのナトリウム形の樹脂が塩酸と接触してこれを水素形とするというように、溶離が順々に行われ、元来水素イオンでは溶離し難いカルシウム形の樹脂を水素イオンより溶離性に優れているナトリウムイオンを介在させることによって効果的に溶離することができると共に、通水終了時に残留する水素形の樹脂をイオン交換樹脂層の下部にそのまま保持しておくことができるため、再生という操作においては最も理想的な状態で再生することができ、再生によって生成される水素形の樹脂を最大とすることができる。本発明は通水の方向が下降流、上昇流に拘らず、両イオン交換樹脂共に通水終了後に逆洗を実施することなく、向流再生を行うため、後述する本発明の全ての実施形態において上述したように最も理想的な状態で両イオン交換樹脂共に再生することができる。
【００３０】
以上説明したように本実施形態によれば、強酸性カチオン交換樹脂と強塩基性アニオン交換樹脂とを一塔内に納めたため、従来の２床３塔式イオン交換装置と比較して装置をコンパクト化することができる。
【００３１】
また、本実施形態では、同一塔内で互いに独立した強酸性カチオン交換樹脂層と強塩基性アニオン交換樹脂層をそれぞれ向流再生するため、上下の各イオン交換樹脂の通水出口側を常に新鮮な再生剤により再生することができ、処理水への不純物イオンのリークを格段に低減することができる。しかも、強酸性カチオン交換樹脂と強塩基性アニオン交換樹脂とは仕切板１４によって上下の各層１２、１３として仕切られ、それぞれ単独のイオン交換樹脂層として形成されているため、従来の混床式イオン交換装置のようにクランピングによる再生不良や逆再生部分が各層１２、１３内に残留することがなく、ひいてはシリカリーク等の不純物イオンのリークがなく、純度の高い処理水を製造することができる。例えばシリカリークについてみると、２床３塔式イオン交換装置の並流再生方式では数ｐｐｂのシリカリークがあり、混床式イオン交換装置では１〜５ｐｐｂのシリカリークがあったのに対し、本実施形態ではシリカリークを０.２ｐｐｂ以下に抑制することができた。
【００３２】
また、本実施形態によれば、原水は下降流で強酸性カチオン交換樹脂、強塩基性アニオン交換樹脂の順で通水し、原水が強塩基性アニオン交換樹脂と直接接触することがないため、原水中にマグネシウムイオン等の硬度成分が多量に含まれている原水を処理する場合にはこれらの硬度成分は上層１２の強酸性カチオン交換樹脂により除去され、下層１３の強塩基性アニオン交換樹脂において水酸化マグネシウム等の難溶性の水酸化物を生成することがない。また、本実施形態によれば、下降流通水を行うため、各イオン交換樹脂層１２、１３が常に固定された固定層になっているため、通水の停止、再開の繰り返し運転が容易である。
【００３４】
図２に示すイオン交換塔１０Ａは、図１に示すイオン交換塔１０における塔本体１１の縦方向中央近傍の仕切板１４の下方に空間を介して第４仕切板１８が設けられていると共に両仕切板１４、１８間の空間に出入管１５が配置され、第４仕切板１８と下層１３の強塩基性アニオン交換樹脂との間に隙間がある以外は図１に示すイオン交換塔１０と同様に構成されている。そして、このイオン交換塔１０Ａにおいても図１に示すイオン交換塔１０と同様に下降流通水、上昇流再生でイオン交換が行われる。
【００３５】
本実施形態によれば、出入管１５が両仕切板１４、１８間の空間に配置され、上下のイオン交換樹脂層１２、１３から隔離されているため、再生工程において後で向流再生する酸再生剤によって下層１３の強塩基性アニオン交換樹脂の上層部が逆再生されることを防止することができ、逆再生部分を生じない分だけ下層１３の強塩基性アニオン交換樹脂のイオン交換容量が増大する。また、その他に、本実施形態においても図１に示すイオン交換塔１０に準じた作用効果を期することができる。
【００３６】
図３に示すイオン交換塔２０は、上昇流通水、下降流再生に用いるイオン交換塔である。従って、塔本体の塔頂、塔底に配置された原水及び各再生剤の流出入配管が逆になっている。本実施形態ではイオン交換塔２０の各構成部材で図１に示すイオン交換塔１０の各構成部材と同一または相当する部材には１０番台の符号に代えて２０番台の符号を附して説明する。
【００３７】
即ち、上記イオン交換塔２０は、図３に示すように、塔本体２１と、この塔本体２１内に強酸性カチオン交換樹脂により形成された上層２２と、上記塔本体２１内に強塩基性アニオン交換樹脂により形成された下層２３と、これら上下各層２２、２３を横方向に仕切る仕切板２４と、この仕切板２４の上方近傍にこれと平行に設けられた出入管２５とを備えている。
【００３８】
そして、原水が流入する流入管２１Ａは塔本体２１の塔底に接続され、その処理水の流出管２１Ｂは塔頂に接続され、原水は流入管２１Ａから塔本体２１内へ上昇流で流入し、上昇流通水の間に下層２３の強塩基性アニオン交換樹脂、上層２２の強酸性カチオン交換樹脂の順でイオン交換され、不純物イオンが除去された処理水が流出管２１Ｂから流出するようにしてある。
【００３９】
また、上記塔本体２１の塔底の流入管２１Ａには下層２３の強塩基性アニオン交換樹脂の再生廃液が流出する第２流出管２１Ｃが接続され、塔頂の流出管２１Ｂには酸再生剤が流入する第２流入管２１Ｄが接続されている。更に、塔本体２１内の出入管２５には外部配管２５Ａが接続され、この外部配管２５Ａからアルカリ再生剤が流入して出入管２５を介して下層２３の強塩基性アニオン交換樹脂全体に分散供給され、また、この出入管２５を介して上層２２の強酸性カチオン交換樹脂からの酸再生廃液が外部配管２５Ａから排出するようにしてある。
【００４０】
従って、再生時には、酸再生剤は第２流入管２１Ｄから供給され、塔本体２１の頂部空間に流入し、第３仕切板２７を介して上層２２の強酸性カチオン交換樹脂の上面全体に分散されて上層２２を下降流で通液し、出入管２５を経由して外部配管２５Ａから排出される。また、アルカリ再生剤は出入管２５を介して上層２２の最下部に流入し、仕切板２４を介して下層２３の強塩基性アニオン交換樹脂の上面全体に分散されて下層２３を下降流で通液し、アルカリ再生廃液が第２仕切板２６を経由して第２流出管２１Ｃから排出される。
【００４１】
再生順序としては、先に通水出口側に位置する上層２２の強酸性カチオン交換樹脂を再生し、後で通水入口側に位置する下層２３の強塩基性アニオン交換樹脂を再生するようにしてある。このように通水出口側である上層２２の強酸性カチオン交換樹脂を先に向流再生することにより、処理水の塩化物イオン等の不純物アニオン量を小さくすることができる。例えば、下層２３である強塩基性アニオン交換樹脂を先に再生すると、後に再生する上層２２である強酸性カチオン交換樹脂の再生剤が処理水の純度に最も影響を与える強塩基性アニオン交換樹脂層の上層部に接触し、再生剤が塩酸である場合には、そのイオン形が一部塩化物イオン形としてしまう。従って、この塩化物イオンが通水中に徐々に脱離することにより、処理水の不純物アニオン量を増加させてしまう。しかしながら、先に上層２２を再生し、後に下層２３を再生する場合には上述のような現象は起こらない。尚、先に上層２２を再生し、後に下層２３を再生する場合には、折角、再生した上層２２の強酸性カチオン交換樹脂に下層２３の再生剤である水酸化ナトリウムが接触し、そのイオン形が一部ナトリウム形となってしまうが、このナトリウム形の樹脂は、強酸性カチン交換樹脂の下層部（通水上流側）に位置することになり、処理水の導電率を低下させる原因とはならない。この関係は前述した図１における全く逆の現象として理解できる。
【００４２】
次に、上記イオン交換塔２０を用いた本発明のイオン交換方法について説明する。通水工程で原水を処理する時には、原水が塔底の流入管２１Ａから塔本体２１内へ上昇流で流入し、第２仕切板２６を介して強塩基性アニオン交換樹脂からなる下層２３下面全面に分散する。下層２３は原水の給水圧によりピストン移動して仕切板２４と接触して固定層を形成し、この状態で原水が通水する間に原水中の硫酸イオン、塩素イオン等のアニオンが強塩基性アニオン交換樹脂により除去される。その後、原水は仕切板２４を介して強酸性カチオン交換樹脂からなる上層２２下面全面に分散し、下層２３と同様に上層２２がピストン移動して第３仕切板２７と接触して固定層を形成し、この状態でアニオン除去後の処理水が通水する間にそのカルシウムイオン、マグネシウムイオン、ナトリウムイオン等のカチオンが強酸性カチオン交換樹脂により除去される。この処理水は第３仕切板２７を経由し、流出管２１Ｂから高純度の純水として流出し、次工程へ供給される。
【００４３】
原水の処理により各イオン交換樹脂が貫流点に達したら再生工程で各イオン交換樹脂を再生する。それには各イオン交換樹脂層を逆洗することなく、まず、通水出口側に位置する上層２２の強酸性カチオン交換樹脂を向流再生する。即ち、酸再生剤として例えば塩酸水溶液を塔頂の第２流入管２１Ｄから下降流で供給すると共に、バランス水を塔底部から上昇流で塔本体２１内へ供給する。これにより酸再生剤は第２仕切板２７を介して上層２２全体に分散し、酸再生剤が上層２２全体を下降流で通液し、この通液の間に強酸性カチオン交換樹脂が再生される。この間、塔底部からバランス水が上昇流で通水されているため、バランス水により酸再生剤の下層２３への侵入を防止する。そして、酸再生廃液はバランス水と出入管２５において合流し、外部配管２５Ａから排出される。上層２２の強酸性カチオン交換樹脂の向流再生後、酸再生剤に代えて純水を塔頂から供給し、塔本体１１の塔頂、塔底の双方から通水して上層２２の強酸性カチオン交換樹脂の押出し、洗浄操作を行い、洗浄廃液は出入管２５、外部配管２５Ａから排出される。
【００４４】
上層の洗浄操作の後、通水入口側に位置する下層２３の強塩基性アニオン交換樹脂を向流再生する。即ち、アルカリ再生剤として例えば水酸化ナトリウム溶液を直胴部の外部配管２５Ａから下降流で供給すると共に、バランス水を塔頂部の第２流入管２１Ｄから塔本体２１内へ下降流で供給する。これによりアルカリ再生剤は出入管２５から上層２２の最下部に流入し、バランス水と合流して仕切板２５を介して下層２３の強塩基性アニオン交換樹脂全体へ下降流で通液される。アルカリ再生剤が下層２３を通液する間に強塩基性アニオン交換樹脂はアルカリ再生剤により効率良く再生される。強塩基性アニオン交換樹脂の向流再生操作が終了したら、引き続き、塔頂のみから純水を下降流通水し、下層２３の強塩基性アニオン交換樹脂を洗浄し、再生操作を終了する。後は、通水工程と再生工程とを逆洗操作を行うことなく繰り返してイオン交換反応により原水を処理して純水を製造する。
【００４５】
従って、本実施形態によれば、原水は上昇流でまず強塩基性アニオン交換樹脂と接触し、ややアルカリ性雰囲気でイオン交換されるため、コロイドシリカのような非イオン状のシリカがアルカリによって溶解してイオン状となって効率良く除去することができる。また、本実施形態では上昇流通水であるため、通水終了時には上下の各層２２、２３はそれぞれ通水時の圧密状態が徐々に解除されながら仕切板２４、２６まで下降する。また、再生工程においてはそれぞれの仕切板２４、２６で支持された状態で再生され、通水工程と再生工程を繰り返しても各イオン交換樹脂層が圧密状態のまま各仕切板２４、２６に固着するということがなく、通水時及び通液時における圧力損失の増大を防止することができる。更に、本実施形態によれば、図１に示すイオン交換樹脂交換塔１０のイオン交換樹脂の層構成に基づく作用効果と同様の作用効果を期することができる。
【００４６】
尚、図３に示した実施形態では、後述する図１１のフローのように、原水を逆浸透膜処理して原水中のカルシウムやマグネシウム等の硬度成分の大部分を予め除去した被処理水や原水を公知のイオン交換装置で処理して得た軟化水や脱塩水を被処理水として処理する場合などに適している。以下に後述する被処理水が最初に強塩基性アニオン交換樹脂層に通水される実施形態についてはいずれも上述したようなことが云える。
【００４７】
図４に示すイオン交換塔２０Ａは、図３に示すイオン交換塔２０における塔本体２１の縦方向中央近傍の仕切板２４の下方に空間を介して第４仕切板２８が設けられていると共に両仕切板２４、２８間の空間に出入管２５が配置され、第４仕切板２８と下層２３の強塩基性アニオン交換樹脂との間に隙間がある以外は図３に示すイオン交換塔２０と同様に構成されている。そして、このイオン交換塔２０Ａにおいても図４に示すイオン交換塔２０と同様に上昇流通水、下降流再生でイオン交換が行われる。
【００４８】
従って、本実施形態によれば、出入管２５が両仕切板２４、２８間の空間に配置され、上下のイオン交換樹脂層２２、２３から隔離されているため、再生工程において後で向流再生するアルカリ再生剤によって上層２２の強酸性カチオン交換樹脂が逆再生されることがなく、逆再生部分を生じない分だけ上層２２の強酸性カチオン交換樹脂のイオン交換容量を増大することができる。また、その他、本実施形態においても図３に示すイオン交換塔２０と同様の作用効果を期することができる。
【００４９】
図５に示すイオン交換塔３０は、図１に示すイオン交換塔１０の場合とは強酸性カチオン交換樹脂層と強塩基性アニオン交換樹脂層の上下関係が逆になっていると共に各イオン交換樹脂の再生剤の給排位置を変えて下降流通水、上昇流再生により向流再生を行うように構成されている。これらの点以外は図１に示すイオン交換塔１０に準じて構成されている。従って、各構成部材は図１に示すイオン交換塔１０の各構成部材と同一または相当する部材には３０番台の符号を附し、その説明を省略する。
【００５０】
次に、上記イオン交換塔３０を用いた本発明にイオン交換方法について説明する。通水工程で原水を処理する時には、塔頂の流入管３１Ａから塔本体３１内へ原水が下降流で流入し、第３仕切板３７を介して強塩基性アニオン交換樹脂からなる上層３２を下降流で通水される間に原水中の硫酸イオン、塩素イオン等のアニオンやシリカが強塩基性アニオン交換樹脂により除去される。その後、アニオンが除去された処理水は仕切板３４を介して強酸性カチオン交換樹脂からなる下層３３を下降流で通水する間にカルシウムイオン、マグネシウムイオン、ナトリウムイオン等のカチオンが強酸性カチオン交換樹脂により除去される。この処理水は第２仕切板３６を経由し、流出管３１Ｂから高純度の純水として流出し、次工程へ供給される。
【００５１】
原水の処理により各イオン交換樹脂が貫流点に達したら再生工程で各イオン交換樹脂を再生する。それには各イオン交換樹脂層を逆洗することなく、まず、通水出口側に位置する下層３３の強酸性カチオン交換樹脂を向流再生する。即ち、酸再生剤として例えば塩酸水溶液を塔底の第２流入管３１Ｄから上昇流で供給すると共に、バランス水を塔頂部から下降流で塔本体３１内へ供給する。これにより酸再生剤は塔底の空間に流入し、第２仕切板３６を介して下層３３全体へ上昇流で通液される。この時、下層３３は酸再生剤の供給圧により上昇し仕切板３４と接触し、この状態で通液し続けると、強酸性カチオン交換樹脂が酸再生剤により効率良く再生され、この時の酸再生廃液は出入管３５を経由して外部配管３５Ａから排出される。下層３３の強酸性カチオン交換樹脂の向流再生を行った後、酸再生剤に代えて純水を塔底から供給し、塔本体３１の塔頂、塔底の双方から通水して下層３３の強酸性カチオン交換樹脂の洗浄操作を行い、洗浄廃液は出入管３５、外部配管３５Ａから排出される。
【００５２】
下層の洗浄操作の後、通水入口側に位置する上層３２の強塩基性アニオン交換樹脂を向流再生する。即ち、下層３３の洗浄水はバランス水として供給すると共に、外部配管３５Ａからアルカリ再生剤として例えば水酸化ナトリウム水溶液を上昇流で塔本体３１内へ供給する。これによりアルカリ再生剤は出入管３５を介して仕切板３４の下側の隙間に流入し、ここでバランス水と合流し、仕切板３４を介して強塩基性アニオン交換樹脂からなる上層３２全体へ上昇流で通液される。この通液に伴って上層３２は上昇して第３仕切板３７と接触する。この状態でアルカリ再生剤を通液し続けると、アルカリ再生剤により強塩基性アニオン交換樹脂は効率良く再生され、この時のアルカリ再生廃液は第２流出管３１Ｃから排出される。強塩基性アニオン交換樹脂の向流再生後、アルカリ再生剤の供給を停止し、塔底のみから純水を上昇流通水して上層３２の強塩基性アニオン交換樹脂の洗浄操作を行う。後は、通水工程と再生工程とを逆洗操作を行うことなく繰り返してイオン交換反応により原水を処理して純水を製造する。
【００５３】
従って、本実施形態によれば、図１に示すイオン交換塔１０の下降流通水、上昇流再生による効果、及び図３に示すイオン交換塔２０の両イオン交換樹脂層の通水順序による効果を期することができる。
【００５４】
図６に示すイオン交換塔３０Ａは、図５に示すイオン交換塔３０における塔本体３１の縦方向中央近傍の仕切板３４の下方に空間を介して第４仕切板３８が設けられていると共に両仕切板３４、３８間の空間に出入管３５が配置され、第４仕切板３８と下層３３の強酸性カチオン交換樹脂の間に隙間がある以外は図５に示すイオン交換塔３０と同様に構成されている。そして、このイオン交換塔３０Ａにおいても図５に示すイオン交換塔３０と同様に下降流通水、上昇流再生でイオン交換が行われる。
【００５５】
従って、本実施形態によれば、出入管３５が両仕切板３４、３８間の空間に配置され、上下のイオン交換樹脂層３２、３３から隔離されているため、再生工程において後で向流再生するアルカリ再生剤によって下層３３の強酸性カチオン交換樹脂が逆再生されることがなく、逆再生部分を生じない分だけ下層３３の強酸性カチオン交換樹脂のイオン交換容量が増大する。また、その他に、本実施形態においても図５に示すイオン交換塔３０に準じた作用効果を期することができる。
【００５６】
図７に示すイオン交換塔３０Ｂは、図５に示すイオン交換塔３０における塔本体３１の縦方向中央近傍の仕切板３４が省略されて上層３２と下層３３とが直接積層され、下層３３の強酸性カチオン交換樹脂の上部に出入管３５が埋設されている以外は図５に示すイオン交換塔３０と同様に構成されている。そして、このイオン交換塔３０Ｂにおいても図５に示すイオン交換塔３０と同様に下降流通水、上昇流再生でイオン交換が行われる。従って、本実施形態によれば、上層３２の強塩基性アニオン交換樹脂と下層３３の強酸性カチオン交換樹脂とが比重差により区画されているだけのため、両イオン交換樹脂層の界面で両者が僅かに混合し、後で行われる強塩基性アニオン交換樹脂の再生時に下層３３の強酸性カチオン交換樹脂の出入管３５より上の部分がアルカリ再生剤により逆再生されるが、この部分は通水時には上流側に位置するため、強酸性カチオン交換樹脂のイオン交換容量は低下するが、処理水の水質には影響しない。また、本実施形態においても図５に示すイオン交換塔３０に準じた作用効果を期することができる。
【００５７】
本発明においては、強酸性カチオン交換樹脂を上層あるいは下層に、また、強塩基性アニオン交換樹脂を上層あるいは下層に積層充填し、この積層を維持したまま通水及び再生を行うことを基本操作とするが、強酸性カチオン交換樹脂と強塩基性アニオン交換樹脂を仕切板で分割する場合と、仕切板で分割することなく、直接両イオン交換樹脂を積層する場合とがある。但し、強酸性カチオン交換樹脂を上層に、強塩基性アニオン交換樹脂を下層にして充填する場合には、強酸性カチオン交換樹脂の比重が強塩基性アニオン交換樹脂の比重より大きいため、逆洗は実施しないものの、相互にその流れ方向と逆方向の通水と再生を繰り返すことにより次第に強酸性カチオン交換樹脂粒子が強塩基性アニオン交換樹脂層に侵入し、処理水の純度を低下させる傾向となる。従って、このような積層充填の場合には両イオン交換樹脂を仕切板で分割することが好ましい。一方、図７等に示したように強塩基性アニオン交換樹脂を上層にして積層する場合には通水と再生を繰り返しても上層の強塩基性アニオン交換樹脂粒子が下層の強酸性カチオン交換樹脂層に侵入し難いため、仕切板の設置を省略することができる。
【００５８】
図８に示すイオン交換塔４０は、図３に示すイオン交換塔２０の場合とは強酸性カチオン交換樹脂層と強塩基性アニオン交換樹脂層の上下関係が逆になっていると共に各イオン交換樹脂の再生剤の給排位置を変えて上昇流通水、下降流再生の向流再生を行うように構成されている。これらの点以外は図３に示すイオン交換塔２０に準じて構成されている。従って、各構成部材は図３に示すイオン交換塔２０の各構成部材と同一または相当する部材には４０番台の符号を附し、その説明を省略する。
【００５９】
次に、上記イオン交換塔４０を用いた本発明にイオン交換方法について説明する。通水工程で原水を処理する時には、原水が塔底の流入管４１Ａから塔本体４１内へ上昇流で流入し、第２仕切板４６を介して強酸性カチオン交換樹脂からなる下層４３下面全面に分散する。下層４３は原水の給水圧によりピストン移動して仕切板４４と接触して固定層を形成し、この状態で原水が通水する間に原水中のカルシウムイオン、マグネシウムイオン、ナトリウムイオン等のカチオンが強酸性カチオン交換樹脂により除去される。その後、原水は仕切板４４を介して強塩基性アニオン交換樹脂からなる上層４２下面全面に分散し、下層４３と同様に上層４２がピストン移動して第３仕切板４７と接触して固定層を形成し、この状態でアニオン除去後の処理水が通水する間にその硫酸イオン、塩素イオン等のアニオンやシリカが強塩基性アニオン交換樹脂により除去される。この処理水は第３仕切板４７を経由し、流出管４１Ｂから高純度の純水として流出し、次工程へ供給される。
【００６０】
原水の処理により各イオン交換樹脂が貫流点に達したら再生工程で各イオン交換樹脂を再生する。それには各イオン交換樹脂層を逆洗することなく、まず、通水出口側に位置する上層４２の強塩基性アニオン交換樹脂を向流再生する。即ち、アルカリ再生剤として例えば水酸化ナトリウム水溶液を塔頂の第２流入管４１Ｄから下降流供給すると共に、バランス水を塔底部から塔本体４２内へ上昇流で供給する。これによりアルカリ再生剤は第２仕切板４７を介して上層４２全体に分散し、アルカリ再生剤が上層４２全体を下降流で通液し、この通液の間に強塩基性アニオン交換樹脂が再生される。この間、塔底部からバランス水が上昇流で通水されているため、バランス水によりアルカリ再生剤の下層４３への侵入を防止する。そして、アルカリ再生廃液は出入管４５においてバランス水と合流し、外部配管４５Ａから排出される。上層４２の強塩基性アニオン交換樹脂の向流再生後、アルカリ再生剤に代えて純水を塔頂から供給し、塔本体４１の塔頂、塔底の双方から通水して上層４２の強塩基性アニオン交換樹脂の洗浄操作を行い、洗浄廃液は出入管４５、外部配管４５Ａから排出される。
【００６１】
上層の洗浄操作の後、通水入口側に位置する下層４３の強酸性カチオン交換樹脂を向流再生する。即ち、酸再生剤として例えば塩酸水溶液を直胴部の外部配管４５Ａから下降流で供給すると共にバランス水を塔頂部から下降流で供給する。これにより酸再生剤は出入管４５から上層４２の最下部に流入し、バランス水と合流して仕切板４４を介して下層４３の強酸性カチオン交換樹脂全体へ下降流で通液される。酸再生剤が下層４３を通液する間に強酸性カチオン交換樹脂は効率良く再生される。強酸性カチオン交換樹脂の向流再生操作が終了したら、引き続き、塔頂のみから純水を下降流通水し、下層４３の強酸性カチオン交換樹脂を洗浄し、再生操作を終了する。後は、通水工程と再生工程とを逆洗操作を行うことなく繰り返してイオン交換反応により原水を処理して純水を製造する。
【００６２】
従って、本実施形態によれば、図３に示すイオン交換塔２０の上昇流通水、下降流再生による効果、及び図１に示すイオン交換塔１０の両イオン交換樹脂層の通水順序による効果を期することができる。
【００６３】
図９に示すイオン交換塔４０Ａは、図８に示すイオン交換塔４０における塔本体４１の縦方向中央近傍の仕切板４４の下方に空間を介して第４仕切板４８が設けられていると共に両仕切板４４、４８間の空間に出入管４５が配置され、第４仕切板４８と下層４３の強酸性カチオン交換樹脂との間に隙間がある以外は図８に示すイオン交換塔４０と同様に構成されている。そして、このイオン交換塔４０Ａにおいても図８に示すイオン交換塔４０と同様に上昇流通水、下降流再生でイオン交換が行われる。
【００６４】
従って、本実施形態によれば、出入管４５が両仕切板４４、４８間の空間に配置され、上下のイオン交換樹脂層４２、４３から隔離されているため、再生工程において後で向流再生する酸再生剤によって上層４２の強塩基性アニオン交換樹脂が逆再生されることがなく、逆再生部分を生じない分だけ上層４２の強塩基性アニオン交換樹脂のイオン交換容量が増大する。また、その他に、本実施形態においても図８に示すイオン交換塔４０に準じた作用効果を期することができる。
【００６５】
図１０に示すイオン交換塔４０Ｂは、図８に示すイオン交換塔４０における塔本体の縦方向中央近傍の仕切板が省略されて上層４２と下層４３とが直接積層されている以外は図８に示すイオン交換塔４０と同様に構成されている。そして、このイオン交換塔４０Ｂにおいても図８に示すイオン交換塔４０と同様に上昇流通水、下降流再生でイオン交換が行われる。従って、本実施形態によれば、上層４２の強塩基性アニオン交換樹脂と下層４３の強酸性カチオン交換樹脂とが比重差により区画されているだけのため、両イオン交換樹脂層の界面で両者が僅かに混合し、後で行われる強酸性カチオン交換樹脂の再生時に上層４２の強塩基性アニオン交換樹脂の出入管４５より下の部分が酸再生剤により逆再生されるが、この部分は通水時には上流側に位置するため、強塩基性アニオン交換樹脂のイオン交換容量は低下するが、処理水の水質には影響しない。また、本実施形態においても図８に示すイオン交換塔４０に準じた作用効果を期することができる。
【００６６】
図１１は前述したように例えば図３に示すイオン交換塔２０を純水製造装置に適用した図を示す。この純水製造装置の場合には、イオン交換塔２０が逆浸透膜装置５０の下流側に配置され、逆浸透膜装置５０により原水中の微粒子が除去されると共に、硬度成分の大部分が除去された透過水がイオン交換塔２０に流入するように構成されている。このようにイオン交換塔２０を逆浸透膜装置５０の下流側に配置することにより、イオン交換樹脂層が微粒子の蓄積により、その圧力損失が増大することがなく、更に、強塩基性アニオン交換樹脂層に水酸化マグネシウム等が発生することがなく、長期間に渡って安定した運転を行うことができる。
【００６７】
尚、図示してないが、炭酸水素カルシウムや炭酸水素マグネシウムを含む被処理水を処理するに当たり、弱酸性カチオン交換樹脂と脱炭酸塔を組み合わせた脱アルカリ軟化装置でまず被処理水を処理した後、本発明の各イオン交換塔で処理することもできる。Ｈ形弱酸性カチオン交換樹脂に上記被処理水を通水すると、炭酸水素イオンに対応するカルシウムイオン、マグネシウムイオンはイオン交換され、炭酸水素イオンは遊離炭酸となる。従って、これを脱炭酸塔で処理することにより、遊離炭酸の大部分を除去することができる。このような処理方法を採用すれば、炭酸水素イオンは本発明のイオン交換塔のイオン負荷から除くことができ、より低コストで純水を得ることができる。また、弱酸性カチオン交換樹脂は再生効率は良いため、その再生に当たっては本発明のイオン交換塔における強酸性カチオン交換樹脂を再生した再生廃液を利用することができる。
【００６８】
また、本発明に用いるイオン交換塔を例えば２基設置した場合には、メリーゴーランド方式により運転することにより各イオン交換樹脂の利用効率を高め、連続的に効率良く純水を製造することができる。
【００６９】
尚、図１１ではイオン交換塔２０を逆浸透膜装置５０の下流側に配置したものについて説明したが、その他の図２〜図１０に示したイオン交換塔も同様に図１１に示す純水製造装置に適用することができる。
【００７０】
【発明の効果】
以上説明したように本発明の請求項１〜請求項１１に記載の発明によれば、次のような種々の効果を達成することができる。
（１）強酸性カチオン交換樹脂と強塩基性カチオン交換樹脂を一塔内に充填したため、塔数を最小にすることができ、イオン交換装置をコンパクト化することができ、設置コスト及び設置面積を大幅に削減することができる。
（２）一塔内に両イオン交換樹脂を充填するとは云え、従来のように両イオン交換樹脂を混合することなく、両イオン交換樹脂の積層状態を維持したまま通水及び再生を行うため、従来の混床式イオン交換装置で発生したような両イオン交換樹脂によるクランピング現象による再生不良を生じることなく、しかも、向流再生を行うため、処理水中のシリカに関しては混床式イオン交換装置よりむしろ優れている。即ち、混床式イオン交換装置においては、再生後にイオン交換樹脂を混合するため、再生によって残留したシリカ形の強塩基性アニオン交換樹脂が全樹脂層に分散して平均化してしまい、処理水のシリカリークは、この平均化したシリカ形の分率によって決定されるが、本発明は向流再生であるため、処理水流出側は完全に再生されており、シリカリークが極めて少ない。
（３）積層させた強酸性カチオン交換樹脂と強塩基性アニオン交換樹脂を再生するに当たり、通水後に逆洗を実施することなく向流再生を行うため、再生操作そのものを理想的な状態で行うことができ、再生剤の使用量当たりの再生後に生成させるＨ形強酸性カチオン交換樹脂あるいはＯＨ形強塩基性アニオン交換樹脂の量を最大にすることができ、処理容量を大きくすることができる。
（４）積層させた両イオン交換樹脂を再生するに当たり、強酸性カチオン交換樹脂から強塩基性アニオン交換樹脂へ通水する場合には強塩基性アニオン交換樹脂を再生した後強酸性カチオン交換樹脂を再生し、強塩基性アニオン交換樹脂から強酸性カチオン交換樹脂へ通水する場合には強酸性カチオン交換樹脂を再生した後強塩基性アニオン交換樹脂を再生するというように、両イオン交換樹脂に被処理水を通水する順序と逆の順序で再生することにより、後から再生する一方のイオン交換樹脂の再生剤が先に再生した他方のイオン交換樹脂と接触して塩形となってもこの塩形が最上流部に位置するため、処理水の純度に全く影響を与えないようにすることができる。
（５）両イオン交換樹脂を仕切板によって仕切ることにより通水と再生を繰り返し行っても両イオン交換樹脂が混合することなく、安定したイオン交換操作を実施することができる。
（６）逆浸透膜装置を設置し、被処理水を逆浸透膜装置により処理し、その透過水を本発明に用いるイオン交換塔で処理するフローにより微粒子の蓄積によるイオン交換樹脂層の圧力損失の増大等の障害を防止することができ、更に、強塩基性アニオン交換樹脂を先に接触させる場合であっても強塩基性アニオン交換樹脂層に水酸化マグネシウム等の沈澱物を発生させることがなく、高純度の処理水を得ることができる。
【図面の簡単な説明】
【図１】本発明のイオン交換方法に好適に用いられるイオン交換塔の一実施形態を示す構成図である。
【図２】本発明のイオン交換方法に好適に用いられるイオン交換塔の他の実施形態を示す構成図である。
【図３】本発明のイオン交換方法に好適に用いられるイオン交換塔の更に他の実施形態を示す構成図である。
【図４】本発明のイオン交換方法に好適に用いられるイオン交換塔の更に他の実施形態を示す構成図である。
【図５】本発明のイオン交換方法に好適に用いられるイオン交換塔の更に他の実施形態を示す構成図である。
【図６】本発明のイオン交換方法に好適に用いられるイオン交換塔の更に他の実施形態を示す構成図である。
【図７】本発明のイオン交換方法に好適に用いられるイオン交換塔の更に他の実施形態を示す構成図である。
【図８】本発明のイオン交換方法に好適に用いられるイオン交換塔の更に他の実施形態を示す構成図である。
【図９】本発明のイオン交換方法に好適に用いられるイオン交換塔の更に他の実施形態を示す構成図である。
【図１０】本発明のイオン交換方法に好適に用いられるイオン交換塔の更に他の実施形態を示す構成図である。
【図１１】図１に示すイオン交換塔を適用した純水製造装置の要部を示すフロー図である。
【符号の説明】
１０、２０、３０、４０ イオン交換塔
１０Ａ、２０Ａ、３０Ａ、４０Ａ イオン交換塔
１１、２１、３１、４１ 塔本体
１２、２２、３２、４２ 上層（イオン交換樹脂層）
１３、２３、３３、４３ 下層（イオン交換樹脂層）
１４、２４、３４、４４ 仕切板
１５、２５、３５、４５ 出入管
１８、２８、３８、４８ 第３仕切板
３０Ｂ、４０Ｂ イオン交換塔[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an ion exchange method and an ion exchange tower used in the ion exchange method, and more specifically, for example, suitably used when producing pure water used for cleaning water for boiler feed water or electronic parts. The present invention relates to an ion exchange method and an ion exchange column used in the ion exchange method.
[0002]
[Prior art]
Typical examples of conventional ion exchange methods and ion exchange columns include a two-bed three-column ion exchange device and a mixed bed ion exchange device. The two-bed / three-column ion exchange apparatus includes, for example, a cation exchange column filled with a strongly acidic cation exchange resin, an anion exchange column filled with a strongly basic anion exchange resin, and a decarboxylation disposed between the two. For example, after ion exchange of calcium ions, magnesium ions, sodium ions, etc. in the raw water with hydrogen ions of the strongly acidic cation exchange resin in the cation exchange tower by the downward flowing water of the raw water, Carbonate ions are decarboxylated under acidic conditions, and then ion exchange of sulfate ions, chloride ions, and other anions and silica in the raw water with hydroxide ions of strongly basic anion exchange resin is performed by descending circulating water in the anion exchange tower. And pure water is produced. When regenerating each of the ion exchange resins, for example, the regenerant is passed through each ion exchange tower in a downward flow to perform cocurrent regeneration, or each regenerant is passed in an up flow. And countercurrent regeneration is performed.
[0003]
On the other hand, the mixed bed type ion exchange apparatus includes an ion exchange tower having a packed bed composed of a mixed ion exchange resin layer in which a strongly acidic cation exchange resin and a strongly basic anion exchange resin are mixed. Thus, pure water with high purity is produced by simultaneously exchanging cations and anions in the raw water with high efficiency in the ion exchange tower. When each ion exchange resin is regenerated, the mixed ion exchange resin layer is backwashed and separated in the same column. Due to the specific gravity difference of each ion exchange resin, a strong basic anion exchange resin layer is formed in the upper layer and a strong acidity is formed in the lower layer. After forming the cation exchange resin layer, the respective regenerants are passed through each ion exchange resin layer to regenerate both ion exchange resins individually. This regeneration operation may be performed in the same column, or each ion exchange resin may be individually extracted in another column and may be individually regenerated in each column.
[0004]
[Problems to be solved by the invention]
However, in the case of the conventional two-bed / three-column ion exchange apparatus, the tower structure is a three-column structure including a cation tower, a decarbonation tower, and an anion tower. There was a problem that it would be expensive. On the other hand, in the case of a mixed bed type ion exchange apparatus, only one ion exchange tower is required and the apparatus itself can be reduced in size, but a strongly acidic cation exchange resin and a strongly basic anion exchange resin are mixed. Therefore, a so-called clamping phenomenon may occur in which both ion exchange resins adhere to each other to form a mixed resin lump. This mixed resin mass is difficult to completely separate by the backwash separation operation during regeneration, and the mixed resin mass is present in both the strongly acidic cation exchange resin layer and the strongly basic anion exchange resin layer after separation by the backwash separation operation. Therefore, even if the regeneration operation is performed, the mixed resin lump existing in each layer becomes defective in regeneration, or the mixed resin lump is reversely regenerated in each layer. When mixing operation is performed in this state, for example, a strongly acidic cation exchange resin reversely regenerated to the sodium form releases sodium, and a strongly basic anion exchange resin regenerated to the chlorine ion form releases the chloride ion form. However, these impurities released near the tower outlet are not removed, and the purity of the treated water is lowered. Even in the absence of such a clamping phenomenon, the ion exchange resin layer located on the outlet side at the time of regeneration flow tends to have a slight amount of impurity ions remaining. The mixing operation prior to passing water results in a uniform distribution in the layer, so that impurity ions are released when the water flows and the purity of the treated water is lowered. For example, silica is an impurity that tends to remain in the resin grains after regeneration, and a silica leak of about 1 to 5 ppb cannot be avoided in a mixed bed type apparatus that performs a mixing operation before passing water. In the case of the mixed bed type, since the backwash separation operation is performed in the ion exchange tower in the regeneration process, the tower height is required to be about twice the height of the packed bed. There was a problem that could not be done. In addition, when the regeneration operation is performed in a separate tower, a separate regeneration tower is required, and an increase in the size of the apparatus cannot be avoided.
[0005]
As an ion exchange device that prevents mixed ion exchange resin clamping, for example, there is also a multilayer ion exchange device in which a strongly basic anion exchange resin layer is laminated on a strongly acidic cation exchange resin layer and descending water flows. In the case of this apparatus, for example, the upper strong base anion exchange resin layer is regenerated by the descending flowing liquid, and the lower strong acid cation exchange resin layer is regenerated by the rising flowing liquid. There is a problem that impurity ions such as silica remain in the lower layer part of the exchange resin, or reverse regeneration parts are generated by the mutual regenerant near the interface between both ion exchange resin layers, and sufficient purity cannot be obtained. Further, in the case of this multi-layer type ion exchange apparatus, since raw water first comes into contact with a strongly basic anion exchange resin layer, when applied to raw water having a high hardness component, hydroxylation is performed in the strongly basic anion exchange resin layer when water is passed. In order to produce a poorly soluble substance such as magnesium, a water softener must be installed in the previous stage, and there is a problem of increasing the size of the apparatus.
[0006]
The present invention has been made in order to solve the above-described problems. The ion exchange apparatus can be made compact, there is no regeneration failure due to clamping, and there is no leakage of impurity ions such as silica leakage, and high purity. Exchange method capable of producing water of the same and ion exchange used in this ion exchange method Tower The purpose is to provide.
[0007]
[Means for Solving the Problems]
In the ion exchange method according to claim 1 of the present invention, a water passing step of passing water to be treated into each of the strongly acidic cation exchange resin layer and the strongly basic anion exchange resin layer formed in the same tower, A regenerating process including an operation of passing each regenerant through each of the ion exchange resin layers, wherein the water passing process and the regenerating process are alternately performed. The treated water is passed through one ion exchange resin layer of both ion exchange resin layers while maintaining the laminated state of the ion exchange resin, and then passed through the other ion exchange resin layer. , Without performing the back washing operation of both the ion exchange resins, the respective regenerants are passed through the respective ion exchange resin layers in the direction opposite to the direction in which the water to be treated is passed. At the same time, the both ion exchange resins are regenerated in the reverse order of passing the water to be treated through the both ion exchange resins. It is characterized by this.
[0009]
Further, the claims of the present invention 2 In the ion exchange method described in 1), water to be treated is passed through the strong acid cation exchange resin layer formed as the upper layer and the strongly basic anion exchange resin layer formed as the lower layer in the same tower in a downward flow from the upper layer to the lower layer. An ion exchange method that includes a water-passing step and a regeneration step including an operation of passing each regenerant in an upward flow through each ion-exchange resin layer, and alternately performing the water-passing step and the regeneration step. In the regeneration step after the completion of the water flow step, the regenerant is first passed through the strong base anion exchange resin in the lower layer without performing the back washing operation of the both ion exchange resins. The regenerant is passed through a strong acidic cation exchange resin in the upper layer.
[0010]
Further, the claims of the present invention 3 In the ion exchange method described in 1), water to be treated is passed through the strong acid cation exchange resin layer formed as the upper layer and the strongly basic anion exchange resin layer formed as the lower layer in the same tower in an upward flow from the lower layer to the upper layer. An ion exchange method that includes a water-passing step and a regeneration step including an operation of passing each regenerant in a downward flow through each of the ion exchange resin layers, and alternately performing the water-passing step and the regeneration step. In the regeneration step after completion of the water flow step, the regenerant is first passed through the strong acidic cation exchange resin of the upper layer without performing the backwash operation of the both ion exchange resins, and then the lower layer. The regenerant is passed through a strongly basic anion exchange resin.
[0011]
Further, the claims of the present invention 4 In the ion exchange method described in 1), water to be treated is passed through the strong base anion exchange resin layer formed as the upper layer and the strong acid cation exchange resin layer formed as the lower layer in the same tower in a downward flow from the upper layer to the lower layer. An ion exchange method that includes a water-passing step and a regeneration step including an operation of passing each regenerant in an upward flow through each ion-exchange resin layer, and alternately performing the water-passing step and the regeneration step. In the regeneration step after the completion of the water flow step, the regenerant is first passed through the strongly acidic cation exchange resin in the lower layer without performing the back washing operation of the both ion exchange resin layers, and then The regenerant is passed through the upper strong base anion exchange resin layer.
[0012]
Further, the claims of the present invention 5 In the ion exchange method described in 1), the water to be treated is passed through the strong base anion exchange resin layer formed as the upper layer and the strong acid cation exchange resin layer formed as the lower layer in the same tower in an upward flow from the lower layer to the upper layer. Ion exchange method comprising: a water-passing step, and a regeneration step including an operation of passing each regenerant in a downward flow through each of the ion exchange resin layers, and alternately performing the water-passing step and the regeneration step. In the regeneration step after completion of the water-passing step, the regenerant is first passed through the strong basic anion exchange resin in the upper layer without performing the backwash operation of both ion-exchange resin layers, and then The regenerant is passed through a strongly acidic cation exchange resin in the lower layer.
[0013]
Further, the claims of the present invention 6 The ion exchange method according to claim 1 is a claim. 5 In the invention according to any one of the above, permeated water previously treated by a reverse osmosis membrane device is used as the water to be treated.
[0014]
Further, the claims of the present invention 7 The ion exchange tower described in A water passing step for passing water to be treated in a downward flow from the upper layer to the lower layer through the strongly acidic cation exchange resin layer formed as the upper layer and the strongly basic anion exchange resin layer formed as the lower layer in the same tower; A regeneration step including an operation of passing each regenerant in an upward flow through the ion exchange resin layer, and the regeneration after completion of the water flow step when the water flow step and the regeneration step are alternately performed. In the process, without performing the back-washing operation of the both ion exchange resins, the regenerant is first passed through the strongly basic anion exchange resin in the lower layer, and then the regenerant is added to the strongly acidic cation exchange resin in the upper layer. Circulate An ion exchange tower used in an ion exchange method by descending circulating water and upward flow regeneration, in which a partition plate for partitioning an upper strong acid cation exchange resin layer and a lower strong base anion exchange resin layer is laterally arranged in the tower. And an inlet / outlet pipe for the regenerant in the vicinity of the lower part of the partition plate, and the partition plate is configured to allow the water to be treated to flow, but to block the flow of the ion exchange resins. It is what.
[0015]
Further, the claims of the present invention 8 The ion exchange tower described in A water passing step of passing water to be treated in an upward flow from the lower layer to the upper layer through the strongly acidic cation exchange resin layer formed as the upper layer and the strongly basic anion exchange resin layer formed as the lower layer in the same tower; A regeneration step including an operation of passing each regenerant in a downward flow through the ion exchange resin layer, and the regeneration after completion of the water flow step when the water flow step and the regeneration step are alternately performed. In the process, without performing the back washing operation of the both ion exchange resins, the regenerant is first passed through the strong acidic cation exchange resin in the upper layer, and then the regenerant is added to the strongly basic anion exchange resin in the lower layer. Let it through, An ion exchange tower used in an ion exchange method by ascending circulation water and downflow regeneration, and a partition plate for partitioning an upper strong acid cation exchange resin layer and a lower strong base anion exchange resin layer in a horizontal direction in the tower And an inlet / outlet pipe for the regenerant in the vicinity of the upper part of the partition plate, and the partition plate is configured to allow the water to be treated to flow, but to block the flow of the ion exchange resins. It is what.
[0016]
Further, the claims of the present invention 9 The ion exchange tower described in A water passing step of passing the water to be treated in a downward flow from the upper layer to the lower layer through a strongly basic anion exchange resin layer formed as an upper layer and a strongly acidic cation exchange resin layer formed as a lower layer in the same tower; A regeneration step including an operation of passing each regenerant in an upward flow through the ion exchange resin layer, and the regeneration after completion of the water flow step when the water flow step and the regeneration step are alternately performed. In the process, the regenerant is first passed through the strongly acidic cation exchange resin in the lower layer without performing the back washing operation of the both ion exchange resin layers, and then the regeneration is performed in the strongly basic anion exchange resin layer in the upper layer. Liquid agent Downstream flow water, an ion exchange tower used in an ion exchange method by upward flow regeneration, which allows the flow of treated water through an upper strong basic anion exchange resin layer and a lower strong acid cation exchange resin layer. A partition plate that prevents the flow of each ion-exchange resin was partitioned, or a partition line for the regenerant was provided near the separation boundary surface of the two ion-exchange resin layers or the lower portion of the partition plate without partitioning by the partition plate. It is characterized by.
[0017]
Further, the claims of the present invention 10 The ion exchange tower described in A water passing step of passing water to be treated in an upward flow from the lower layer to the upper layer through the strongly basic anion exchange resin layer formed as the upper layer and the strongly acidic cation exchange resin layer formed as the lower layer in the same tower; A regeneration step including an operation of passing the respective regenerant in a downward flow through both ion exchange resin layers, and when the water flow step and the regeneration step are alternately performed, In the regeneration step, the regenerant is first passed through the strong base anion exchange resin in the upper layer without backwashing the both ion exchange resin layers, and then the regenerant into the strongly acidic cation exchange resin in the lower layer. Pass through Ascending circulation water, an ion exchange tower used in an ion exchange method by downflow regeneration, which allows the flow of treated water through an upper strong basic anion exchange resin layer and a lower strongly acidic cation exchange resin layer, Partitioning with a partition plate that prevents the flow of each ion-exchange resin, or without partitioning with the partition plate, a regenerant inlet / outlet pipe is provided on the separation boundary surface of both the ion-exchange resin layers or near the upper portion of the partition plate. It is characterized by.
[0018]
Further, the claims of the present invention 11 The ion exchange tower described in A water passing step for passing water to be treated to each of the strongly acidic cation exchange resin layer and the strongly basic anion exchange resin layer formed in the same tower, and the respective regenerants through each of the ion exchange resin layers. A regenerating step including an operation to perform the water flow step and the regenerating step alternately. In the water passing step, the water to be treated is treated with both ion exchange resins while maintaining the laminated state of both ion exchange resins. After passing through one ion exchange resin layer of the layer, the other ion exchange resin layer is passed through, and in the regeneration step, each of the ion exchange resin layers is performed without performing a backwash operation of the both ion exchange resins. In addition, the respective regenerants are passed in the direction opposite to the direction in which the water to be treated is passed, and the ion exchange resins are regenerated in the reverse order to the order in which the water to be treated is passed through the both ion exchange resins. Do An ion exchange tower used in an ion exchange method, wherein upper and lower two-stage partition plates for partitioning a strongly acidic cation exchange resin layer and a strongly basic anion exchange resin layer are respectively provided in the tower in a lateral direction through a space. An inlet / outlet pipe for each of the regenerants is provided in a space between the partition plates, and the partition plates are configured to allow the water to be treated to flow but prevent the flow of the ion exchange resins. It is what.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described based on the embodiments shown in FIGS. In addition, in each figure, FIGS. 1-10 is a conceptual diagram which shows embodiment of the ion exchange tower used for the ion exchange method of this invention, respectively, FIG. 11 applied the ion exchange tower shown in FIG. It is a flowchart which shows the principal part of a pure water manufacturing apparatus.
[0020]
The ion exchange tower 10 shown in FIG. 1 is formed with a tower main body 11, an upper layer 12 formed in the tower main body 11 with a strong acid cation exchange resin, and a strong basic anion exchange resin in the tower main body 11. A lower layer 13, a partition plate 14 provided in the tower body 11 so as to partition the upper and lower layers 12, 13 in the middle in the height direction of the tower body 11, and a lower portion of the partition plate 14 An inlet / outlet pipe 15 provided in parallel with this is provided, and is configured to perform downward circulation water and upward flow regeneration. The strongly acidic cation exchange resin of the upper layer 12 is supported by the partition plate 14, and the strongly basic anion exchange resin of the lower layer 13 is supported by the second partition plate 16 provided in the lower part of the tower body 11 in parallel with the partition plate 14. It is supported. Therefore, since the strong acid cation exchange resin of the upper layer 12 is partitioned from the lower layer 13 by the partition plate 14, the strong acid cation exchange resin of the upper layer 12 is not mixed with the strongly basic anion exchange resin of the lower layer 13. Further, a slight gap is formed between the upper surface of the strongly basic anion exchange resin of the lower layer 13 and the partition plate 14 corresponding to the amount of swelling during regeneration, and the inlet / outlet pipe 15 is arranged in this gap. In addition, a third partition plate 17 is provided in the upper part of the tower body 11 in parallel with the partition plate 14, and the upper surface of the third partition plate 17 and the strong acid cation exchange resin layer 12 is a strongly basic anion exchange resin. Similarly, a slight gap corresponding to the amount that swells during reproduction is formed. In the present invention, the gap formed below each partition plate is a slight gap corresponding to the amount of swelling during reproduction as described above, and the meaning of the gap in each embodiment described later is also the same.
[0021]
In addition, each of the partition plates 14, 16, and 17 is formed by uniformly distributing a large number of communication means communicating the upper and lower spaces over the entire surface, and the water to be treated and the regenerant are circulated through these communication means, It is comprised so that each ion exchange resin cannot distribute | circulate. An inflow pipe 11A into which raw water as treated water flows is connected to the top of the tower main body 11, and an outflow pipe 11B from which treated water flows out is connected to the tower bottom. The raw water flowing in is ion-exchanged while passing through the strongly acidic cation exchange resin layer of the upper layer 12 and the strongly basic anion exchange resin layer of the lower layer 13 in order from the outflow pipe 11B as treated water from which impurity ions are removed. It is designed to flow out. In addition, in FIG. 1, the flow related to raw water and treated water and the flow of raw water and treated water are indicated by solid lines. The same applies to FIGS. 2 to 10 showing ion exchange columns of other embodiments to be described later.
[0022]
Further, a second outflow pipe 11C through which the acid regeneration waste solution of the strongly acidic cation exchange resin in the upper layer 12 flows out is connected to the inflow pipe 11A at the top of the tower body 11, and an alkali is connected to the outflow pipe 11B at the bottom of the tower main body 11. The second inflow pipe 11D into which the regenerant flows is connected. Further, an external pipe 15 A is connected to the inlet / outlet pipe 15 in the tower body 11, and the acid regenerant flows from the outer pipe 15 A and is dispersed throughout the strong acid cation exchange resin layer 12 of the upper layer 12 through the inlet / outlet pipe 15. In addition, the alkali regeneration waste liquid from the strong base anion exchange resin layer 13 in the lower layer is discharged from the external pipe 15 </ b> A through the inlet / outlet pipe 15. In FIG. 1, the piping related to the regenerant and the flow of the regenerant are indicated by alternate long and short dash lines. The same applies to FIGS. 2 to 10 showing ion exchange columns of other embodiments to be described later.
[0023]
Therefore, at the time of regeneration, the alkali regenerant flows into the bottom space of the tower body 11 from the second inflow pipe 11D at the bottom of the tower, and is dispersed throughout the lower surface of the strongly basic anion exchange resin in the lower layer 13 through the second partition plate 16. Then, the lower layer 13 is passed through ascending flow, and the alkali regeneration waste liquid is discharged from the external pipe 15 </ b> A via the inlet / outlet pipe 15. Further, the acid regenerant is supplied from the external pipe 15A, flows into the gap between the lower layer 13 and the partition plate 14 through the inlet / outlet pipe 15, and passes through the partition plate 14 to the entire lower surface of the strongly acidic cation exchange resin of the upper layer 12. Dispersed and passed through the upper layer 12 in an upward flow, and the acid regeneration waste liquid is discharged from the second outlet pipe 11 </ b> C via the third partition plate 17. That is, at the time of regeneration of each ion exchange resin, each regenerant is passed in the direction opposite to the direction of flow of raw water, and each ion exchange resin is regenerated by a countercurrent regeneration method. At this time, when regenerating one ion exchange resin layer, pure water is continuously passed through the other ion exchange resin layer as balance water so that one regenerant does not flow into the other ion exchange resin layer. Yes. When supplying the balance water, for example, the inflow pipe 11A and the outflow pipe 11B of the raw water can be used.
[0024]
As the regeneration order, the strongly basic anion exchange resin of the lower layer 13 located on the water flow outlet side is regenerated first, and the strong acid cation exchange resin of the upper layer 12 located on the water flow inlet side is regenerated later. is there. In this way, high-purity treated water can be obtained by first counter-currently regenerating the strongly basic anion exchange resin in the lower layer 13 on the water outlet side. For example, when the strong acid cation exchange resin of the upper layer 12 is regenerated first and then the strong base anion exchange resin of the lower layer 13 is regenerated, the lower layer portion of the strongly acidic cation exchange resin layer highly regenerated by upward flow regeneration is folded. The base part of the strongly acidic cation exchange resin layer that has the most influence on the conductivity of the treated water is in salt form when an alkaline regenerator such as sodium hydroxide aqueous solution, which is a regenerator of the strongly basic anion exchange resin to be regenerated later, comes into contact It will become and will reduce the purity of treated water. On the other hand, when the strongly basic anion exchange resin of the lower layer 13 is regenerated and the strong acid cation exchange resin of the upper layer 12 is regenerated later, high-purity treated water can be obtained without causing the phenomenon described above. it can. When the lower layer 13 is regenerated first and the upper layer 12 is regenerated later, an acid regenerant such as hydrochloric acid, which is the regenerant of the upper layer 12, comes into contact with the upper layer portion of the regenerated strong basic anion exchange resin layer. In this case, since the water to be treated (acid soft water) is the first contact portion, the purity of the treated water is not affected. That is, the strongly basic anion exchange resin layer forming the lower layer 13 is regenerated in an upward flow in FIG. 1, and therefore, the lowermost layer part that most affects chloride ions and silica leaks in the treated water is ideally regenerated. It depends on.
[0025]
In FIG. 1, the inlet / outlet pipe 15 is installed near the lower portion of the partition plate 14 for the following reason. As described above, in the embodiment shown in FIG. 1, when the upper layer (strongly acidic cation exchange resin layer) 12 is regenerated, if the salt form strongly acidic cation exchange resin remains in the upper layer 12 after the regeneration, The purity of water decreases. Therefore, the inlet / outlet pipe 15 is installed below the partition plate 14, and the regenerant is brought into contact with all the strongly acidic cation exchange resins located above the partition plate 14 by allowing the regenerant to flow in from there. Can be eliminated as much as possible. For example, when the inlet / outlet pipe 15 is installed above the partition plate 14, a portion that does not come into contact with the regenerant is generated, which causes a decrease in the purity of the treated water. Also in other embodiments to be described later, with regard to the installation position of the inlet / outlet pipe, consideration is given to the installation of the unregenerated ion exchange resin that affects the purity of the treated water as described above.
[0026]
Next, the ion exchange method of the present invention using the ion exchange tower 10 will be described. When the raw water is treated in the water flow process, the raw water flows into the tower body 11 from the inflow pipe 11A, and is dispersed over the entire upper surface of the upper layer 12 made of the strongly acidic cation exchange resin via the third partition plate 17. This raw water is passed through the entire upper layer 12 by a downward flow, and during this time cations such as calcium ions, magnesium ions, sodium ions, etc. in the raw water are removed by the strongly acidic cation exchange resin. Thereafter, the raw water is dispersed on the entire upper surface of the lower layer 13 made of a strongly basic anion exchange resin through the partition plate 14, and anions such as sulfate ions and chlorine ions and silica in the raw water are strong while passing through the lower layer 13. The high-purity treated water that has been removed by the basic anion exchange resin and from which the anions and cations have been removed flows out from the outflow pipe 11B via the second partition plate 16, and is supplied to the next step.
[0027]
When each ion exchange resin reaches the flow-through point due to the raw water treatment, each ion exchange resin is regenerated in a regeneration step. For this purpose, first, the strongly basic anion exchange resin of the lower layer 13 located on the water outlet side is regenerated countercurrently without backwashing each ion exchange resin layer. That is, as an alkali regenerator, for example, an aqueous sodium hydroxide solution is supplied as an upward flow from the second inflow pipe 11D at the bottom of the tower, and balance water is supplied into the tower body 11 as a downward flow from the top of the tower. As a result, the alkali regenerant flows into the space at the bottom of the tower and is passed through the second partition plate 16 to the entire lower layer 13 in an upward flow. At this time, in the lower layer 13, the entire ion exchange resin layer is moved by the piston by the supply pressure of the alkali regenerant and is pressed against the partition plate 14. If the liquid continues to flow in this state, the strongly basic anion exchange resin is absorbed by the alkali regenerator. The alkali regeneration waste liquid at this time is discharged from the external pipe 15A through the inlet / outlet pipe 15 together with the balance water. After the counter-current regeneration of the strongly basic anion exchange resin of the lower layer 13, pure water is supplied from the bottom of the tower instead of the alkali regenerant, and water is passed from both the top and the bottom of the tower body 11 to lower the lower layer. Extrusion and cleaning operations of 13 strong basic anion exchange resin regenerants are performed, and the cleaning waste liquid is discharged through the inlet / outlet pipe 15 and the external pipe 15A.
[0028]
After the washing operation of the lower layer, the strongly acidic cation exchange resin of the upper layer 12 located on the water inlet side is regenerated countercurrently. That is, the balance water is supplied to the lower layer 13 and the acid regenerant is supplied from the external pipe 15A. As a result, the acid regenerant flows into the lower gap of the partition plate 14 through the inlet / outlet pipe 15, where it merges with the balance water and rises to the entire upper layer 12 made of the strongly acidic cation exchange resin through the partition plate 14. It is passed through the stream. As the liquid passes, the entire ion exchange resin layer of the upper layer 12 moves as a piston and is pressed against the third partition plate 17. If the acid regenerant is continuously passed in this state, the strongly acidic cation exchange resin is efficiently regenerated by the acid regenerator, and the acid regeneration waste liquid at this time is discharged from the second outflow pipe 11C. After the counter-current regeneration of the strong acid cation exchange resin in the upper layer 12, the supply of the acid regeneration agent is stopped, and pure water is flowed up from only the bottom of the column to push and wash the regeneration agent of the strong acid cation exchange resin in the upper layer 12 In operation, the washing waste liquid is discharged from the top of the column. After that, the water flow process and the regeneration process are repeated without performing a backwash operation, and the raw water is treated by an ion exchange reaction to produce pure water.
[0029]
In the present invention, without performing the back washing operation of both ion exchange resin layers after the end of water flow, the respective regenerant is passed in the direction opposite to the direction in which the water to be treated is passed through the both ion exchange resin layers. In order to perform so-called countercurrent regeneration, it can be regenerated as it is without disturbing the arrangement of the ion forms formed in the ion exchange resin layer at the end of water flow, and the regenerated form of the lowest layer remaining at the end of water flow The ion exchange resin can be used effectively and the regeneration efficiency can be maximized. For example, the case of the strongly acidic cation exchange resin of the upper layer 12 in FIG. 1 will be further described. The arrangement of the resin layer when water is passed is calcium, sodium, and hydrogen from the top. Without backwashing, if hydrochloric acid is passed as the acid regenerant from the lower side of the resin layer in this state, the hydrochloric acid passes through the lower layer hydrogen-type resin to elute the sodium-type resin first. The sodium chloride, which is the waste liquid, elutes the calcium resin in the upper layer to make it into the sodium form, and the sodium resin comes into contact with hydrochloric acid to make it into the hydrogen form. In addition, the elution is carried out one after another, and it is effective by interposing sodium ion, which is more difficult to elute than hydrogen ion, in the calcium-type resin, which is originally difficult to elute with hydrogen ion. In addition, the hydrogen-type resin remaining at the end of water flow can be kept under the ion exchange resin layer as it is, so that it can be regenerated in the most ideal state in the operation of regeneration. The hydrogen-type resin produced by regeneration can be maximized. Regardless of whether the direction of water flow is a downward flow or an upward flow, both ion exchange resins perform countercurrent regeneration without performing backwashing after the completion of water flow. As described above, both ion exchange resins can be regenerated in the most ideal state.
[0030]
As described above, according to the present embodiment, the strongly acidic cation exchange resin and the strongly basic anion exchange resin are accommodated in one tower, so that the apparatus is compact compared with the conventional two-bed / three-column ion exchange apparatus. Can be
[0031]
In this embodiment, the strongly acidic cation exchange resin layer and the strongly basic anion exchange resin layer that are independent from each other in the same column are regenerated countercurrently, so that the water outlet side of each of the upper and lower ion exchange resins is always fresh. Can be regenerated with a suitable regenerant, and the leakage of impurity ions to the treated water can be greatly reduced. The Shi Moreover, the strongly acidic cation exchange resin and the strongly basic anion exchange resin are partitioned as upper and lower layers 12 and 13 by the partition plate 14 and are formed as individual ion exchange resin layers, respectively. As in the exchange apparatus, there is no regeneration failure due to clamping and no reverse regeneration portion remains in each of the layers 12 and 13, and consequently there is no leakage of impurity ions such as silica leaks, and high-purity treated water can be produced. . For example, in the case of silica leak, there is a silica leak of several ppb in the parallel flow regeneration method of the two-bed / three-column ion exchange apparatus, and 1-5 ppb of the silica leak in the mixed bed ion exchange apparatus. In the embodiment, silica leak could be suppressed to 0.2 ppb or less.
[0032]
Further, according to the present embodiment, the raw water is passed in the order of the strong acid cation exchange resin and the strong basic anion exchange resin in the descending flow, and the raw water does not come into direct contact with the strong basic anion exchange resin. When raw water containing a large amount of hardness components such as magnesium ions is treated in the raw water, these hardness components are removed by the strongly acidic cation exchange resin of the upper layer 12, and in the strongly basic anion exchange resin of the lower layer 13. No poorly soluble hydroxide such as magnesium hydroxide is produced. In addition, according to the present embodiment, since the ion exchange resin layers 12 and 13 are always fixed in order to perform downward circulation water, repeated operation of stopping and restarting water flow is easy. .
[0034]
The ion exchange column 10A shown in FIG. 2 includes a fourth partition plate 18 provided below the partition plate 14 in the vicinity of the center in the longitudinal direction of the column body 11 in the ion exchange column 10 shown in FIG. The ion exchange column 15 is arranged in the space between the partition plates 14 and 18, and is the same as the ion exchange tower 10 shown in FIG. 1 except that there is a gap between the fourth partition plate 18 and the strongly basic anion exchange resin of the lower layer 13. It is configured. In the ion exchange tower 10A, as in the ion exchange tower 10 shown in FIG. 1, ion exchange is performed by downward flowing water and upward flow regeneration.
[0035]
According to the present embodiment, since the inlet / outlet pipe 15 is disposed in the space between the partition plates 14 and 18 and is isolated from the upper and lower ion exchange resin layers 12 and 13, the acid that is countercurrently regenerated later in the regeneration process. The upper layer part of the strongly basic anion exchange resin in the lower layer 13 can be prevented from being reversely regenerated by the regenerant, and the ion exchange capacity of the strongly basic anion exchange resin in the lower layer 13 is increased by the amount that does not cause the reverse regeneration part. Increase. In addition, also in the present embodiment, an effect similar to that of the ion exchange tower 10 shown in FIG. 1 can be expected.
[0036]
The ion exchange tower 20 shown in FIG. 3 is an ion exchange tower used for upward circulation water and downward flow regeneration. Therefore, the flow-out piping for the raw water and each regenerant disposed at the top and bottom of the tower body is reversed. In the present embodiment, the same or corresponding members of the ion exchange tower 20 as those of the ion exchange tower 10 shown in FIG. .
[0037]
That is, as shown in FIG. 3, the ion exchange tower 20 includes a tower body 21, an upper layer 22 formed of a strongly acidic cation exchange resin in the tower body 21, and a strongly basic anion in the tower body 21. A lower layer 23 formed of an exchange resin, a partition plate 24 that partitions the upper and lower layers 22 and 23 in the horizontal direction, and an inlet / outlet pipe 25 provided in the vicinity of the upper portion of the partition plate 24 in parallel therewith are provided.
[0038]
The inflow pipe 21A into which the raw water flows is connected to the tower bottom of the tower body 21, the outflow pipe 21B of the treated water is connected to the top of the tower, and the raw water flows into the tower body 21 from the inflow pipe 21A. The treated water from which the impurity ions have been removed by the ion exchange in the order of the strongly basic anion exchange resin in the lower layer 23 and the strong acid cation exchange resin in the upper layer 22 flows out from the outflow pipe 21B. is there.
[0039]
Further, a second outflow pipe 21C from which the regeneration waste liquid of the strongly basic anion exchange resin in the lower layer 23 flows out is connected to the inflow pipe 21A at the bottom of the tower main body 21, and the acid regenerant is connected to the outflow pipe 21B at the top of the tower. Is connected to the second inflow pipe 21D. Further, an external pipe 25A is connected to the inlet / outlet pipe 25 in the tower body 21, and an alkaline regenerant flows from the outer pipe 25A and is distributed and supplied to the entire strongly basic anion exchange resin in the lower layer 23 through the inlet / outlet pipe 25. In addition, the acid regeneration waste liquid from the strongly acidic cation exchange resin of the upper layer 22 is discharged from the external pipe 25A through the inlet / outlet pipe 25.
[0040]
Therefore, at the time of regeneration, the acid regenerant is supplied from the second inflow pipe 21D, flows into the top space of the tower main body 21, and is dispersed throughout the upper surface of the strongly acidic cation exchange resin of the upper layer 22 through the third partition plate 27. Then, the upper layer 22 is passed in a downward flow, and is discharged from the external pipe 25 </ b> A via the inlet / outlet pipe 25. Further, the alkali regenerant flows into the lowermost portion of the upper layer 22 through the inlet / outlet pipe 25 and is dispersed throughout the upper surface of the strongly basic anion exchange resin of the lower layer 23 through the partition plate 24 and passes through the lower layer 23 in a downward flow. Then, the alkali regeneration waste liquid is discharged from the second outflow pipe 21 </ b> C via the second partition plate 26.
[0041]
As the regeneration order, the strong acid cation exchange resin of the upper layer 22 located on the water flow outlet side is regenerated first, and the strong base anion exchange resin of the lower layer 23 located on the water flow inlet side is regenerated later. is there. Thus, the amount of impurity anions such as chloride ions in the treated water can be reduced by first counter-currently regenerating the strongly acidic cation exchange resin of the upper layer 22 on the water outlet side. For example, when the strongly basic anion exchange resin that is the lower layer 23 is first regenerated, the strong acid anion exchange resin layer in which the regenerant of the strongly acidic cation exchange resin that is the upper layer 22 to be regenerated later most affects the purity of the treated water. In the case where the regenerant is hydrochloric acid, the ionic form is partially converted to the chloride ion form. Accordingly, the chloride ions are gradually desorbed into the water flow, thereby increasing the amount of impurity anions in the treated water. However, when the upper layer 22 is reproduced first and the lower layer 23 is reproduced later, the above phenomenon does not occur. . When the upper layer 22 is regenerated first and the lower layer 23 is regenerated later, the strongly acidic cation exchange resin of the regenerated upper layer 22 is contacted with sodium hydroxide as the regenerant of the lower layer 23, and its ionic form Will be partly in the form of sodium, but this sodium-type resin will be located in the lower layer (upstream side of the water flow) of the strongly acidic cutin exchange resin, which is why the conductivity of the treated water is reduced. Don't be. This relationship can be understood as a completely opposite phenomenon in FIG.
[0042]
Next, the ion exchange method of the present invention using the ion exchange tower 20 will be described. When the raw water is treated in the water flow process, the raw water flows up into the tower main body 21 from the inlet pipe 21A at the bottom of the tower, and the entire lower surface of the lower layer 23 made of a strongly basic anion exchange resin through the second partition plate 26. To disperse. The lower layer 23 is moved by a piston by the feed pressure of the raw water to come into contact with the partition plate 24 to form a fixed layer. In this state, while the raw water flows, anions such as sulfate ions and chloride ions in the raw water are strongly basic. Removed by anion exchange resin. Thereafter, the raw water is dispersed on the entire lower surface of the upper layer 22 made of a strongly acidic cation exchange resin through the partition plate 24, and the upper layer 22 moves in the same manner as the lower layer 23 to come into contact with the third partition plate 27 to form a fixed layer. In this state, cations such as calcium ions, magnesium ions, and sodium ions are removed by the strongly acidic cation exchange resin while the treated water after removal of the anions is passed. This treated water flows out as high-purity pure water from the outflow pipe 21B via the third partition plate 27 and is supplied to the next step.
[0043]
When each ion exchange resin reaches the flow-through point due to the raw water treatment, each ion exchange resin is regenerated in a regeneration step. For this purpose, first, the strongly acidic cation exchange resin of the upper layer 22 located on the water outlet side is regenerated countercurrently without backwashing each ion exchange resin layer. That is, as an acid regenerating agent, for example, an aqueous hydrochloric acid solution is supplied in a downward flow from the second inflow pipe 21D at the top of the tower, and balance water is supplied into the tower body 21 in an upward flow from the bottom of the tower. As a result, the acid regenerant is dispersed throughout the upper layer 22 through the second partition plate 27, and the acid regenerant passes through the entire upper layer 22 in a downward flow. During this flow, the strongly acidic cation exchange resin is regenerated. The During this time, since the balance water is passed in an upward flow from the bottom of the tower, the balance water prevents the acid regenerant from entering the lower layer 23. Then, the acid regeneration waste liquid merges with the balance water in the inlet / outlet pipe 25 and is discharged from the external pipe 25A. After countercurrent regeneration of the strongly acidic cation exchange resin in the upper layer 22, pure water is supplied from the top of the tower instead of the acid regenerant, and water is passed from both the top and bottom of the tower body 11 to cause strong acidity in the upper layer 22. The cation exchange resin is extruded and washed, and the washing waste liquid is discharged from the inlet / outlet pipe 25 and the outer pipe 25A.
[0044]
After the washing operation of the upper layer, the strongly basic anion exchange resin of the lower layer 23 located on the water inlet side is regenerated countercurrently. That is, for example, a sodium hydroxide solution is supplied as an alkali regenerant in a downward flow from the external pipe 25A in the straight body portion, and balance water is supplied in a downward flow from the second inflow pipe 21D at the top of the tower into the tower body 21. As a result, the alkali regenerant flows from the inlet / outlet pipe 25 into the lowermost portion of the upper layer 22, joins with the balance water, and passes through the partition plate 25 in a downward flow to the entire strongly basic anion exchange resin of the lower layer 23. While the alkali regenerant passes through the lower layer 23, the strongly basic anion exchange resin is efficiently regenerated by the alkali regenerator. When the counter-current regeneration operation of the strong basic anion exchange resin is completed, the pure water is continuously flowed down from only the top of the tower, the strong basic anion exchange resin in the lower layer 23 is washed, and the regeneration operation is completed. After that, the water flow process and the regeneration process are repeated without performing a backwash operation, and the raw water is treated by an ion exchange reaction to produce pure water.
[0045]
Therefore, according to the present embodiment, the raw water first comes into contact with the strongly basic anion exchange resin in an upward flow and is ion-exchanged in a slightly alkaline atmosphere. Therefore, nonionic silica such as colloidal silica is dissolved by alkali. And can be efficiently removed in the form of ions. Moreover, since it is rising circulation water in this embodiment, the upper and lower layers 22 and 23 descend to the partition plates 24 and 26 while gradually releasing the compacted state at the time of water flow when the water flow ends. Further, in the regeneration process, it is regenerated while being supported by the respective partition plates 24 and 26, and each ion exchange resin layer remains fixed in the compacted state even when the water flow process and the regeneration process are repeated. Therefore, it is possible to prevent an increase in pressure loss during water flow and liquid flow. Furthermore, according to this embodiment, the same effect as the effect based on the layer structure of the ion exchange resin of the ion exchange resin exchange tower 10 shown in FIG. 1 can be expected.
[0046]
In the embodiment shown in FIG. 3, as shown in the flow of FIG. 11 to be described later, the water to be treated has been subjected to reverse osmosis membrane treatment to remove most of the hardness components such as calcium and magnesium in the raw water in advance. It is suitable when softened water or demineralized water obtained by treating raw water with a known ion exchange device is treated as water to be treated. It can be said that all of the embodiments in which the water to be treated, which will be described later, is initially passed through the strongly basic anion exchange resin layer, are described above.
[0047]
The ion exchange column 20A shown in FIG. 4 has a fourth partition plate 28 provided through a space below the partition plate 24 in the vicinity of the center in the longitudinal direction of the column body 21 in the ion exchange column 20 shown in FIG. The ion exchange column 25 is disposed in the space between the partition plates 24 and 28, and is the same as the ion exchange tower 20 shown in FIG. 3 except that there is a gap between the fourth partition plate 28 and the strongly basic anion exchange resin of the lower layer 23. It is configured. In the ion exchange tower 20A, as in the ion exchange tower 20 shown in FIG. 4, ion exchange is performed by ascending circulating water and descending flow regeneration.
[0048]
Therefore, according to this embodiment, since the inlet / outlet pipe 25 is disposed in the space between the partition plates 24 and 28 and is isolated from the upper and lower ion exchange resin layers 22 and 23, the countercurrent regeneration is performed later in the regeneration process. The strong acid cation exchange resin of the upper layer 22 is not reversely regenerated by the alkali regenerating agent, and the ion exchange capacity of the strong acid cation exchange resin of the upper layer 22 can be increased by the amount not causing the reverse regeneration portion. In addition, in this embodiment as well, 3 The same effect as the ion exchange tower 20 shown in FIG.
[0049]
The ion exchange column 30 shown in FIG. 5 is different from the case of the ion exchange column 10 shown in FIG. 1 in that the vertical relationship between the strongly acidic cation exchange resin layer and the strongly basic anion exchange resin layer is reversed and each ion exchange resin. The regenerative agent supply / discharge position is changed and counterflow regeneration is performed by descending circulating water and upward flow regeneration. Except for these points, the configuration is the same as that of the ion exchange column 10 shown in FIG. Therefore, each constituent member is the same as or equivalent to each constituent member of the ion exchange tower 10 shown in FIG.
[0050]
Next, an ion exchange method according to the present invention using the ion exchange tower 30 will be described. When the raw water is treated in the water flow process, the raw water flows in a downward flow from the tower top inflow pipe 31A into the tower body 31 and descends the upper layer 32 made of a strongly basic anion exchange resin through the third partition plate 37. While flowing in a stream, anions such as sulfate ions and chloride ions and silica in raw water are removed by a strongly basic anion exchange resin. Thereafter, the treated water from which the anion has been removed passes through the lower plate 33 made of the strongly acidic cation exchange resin through the partition plate 34 in a downward flow, while cations such as calcium ions, magnesium ions, and sodium ions exchange strongly acidic cation. Removed by resin. This treated water flows out from the outflow pipe 31B as high-purity pure water via the second partition plate 36, and is supplied to the next step.
[0051]
When each ion exchange resin reaches the flow-through point due to the raw water treatment, each ion exchange resin is regenerated in a regeneration step. For this purpose, first, the strongly acidic cation exchange resin of the lower layer 33 located on the water outlet side is regenerated countercurrently without backwashing each ion exchange resin layer. That is, for example, an aqueous hydrochloric acid solution is supplied as an acid regenerator from the second inflow pipe 31D at the bottom of the tower in an upward flow, and balance water is supplied into the tower body 31 from the top of the tower as a downward flow. As a result, the acid regenerant flows into the space at the bottom of the tower and is passed through the second partition plate 36 to the entire lower layer 33 in an upward flow. At this time, the lower layer 33 rises due to the supply pressure of the acid regenerant and comes into contact with the partition plate 34. If the liquid continues to flow in this state, the strong acid cation exchange resin is efficiently regenerated by the acid regenerator, and the acid at this time The recycled waste liquid is discharged from the external pipe 35 </ b> A via the inlet / outlet pipe 35. After the counter-current regeneration of the strongly acidic cation exchange resin in the lower layer 33, pure water is supplied from the tower bottom instead of the acid regeneration agent, and water is passed from both the tower top and the tower bottom of the tower body 31 to lower the lower layer 33. The strongly acidic cation exchange resin is washed, and the washing waste liquid is discharged from the inlet / outlet pipe 35 and the outer pipe 35A.
[0052]
After the lower layer washing operation, the strongly basic anion exchange resin in the upper layer 32 located on the water inlet side is regenerated countercurrently. That is, the cleaning water for the lower layer 33 is supplied as balance water and, for example, an aqueous sodium hydroxide solution is supplied as an alkali regenerant from the external pipe 35A into the tower body 31 in an upward flow. As a result, the alkali regenerant flows into the lower gap of the partition plate 34 via the inlet / outlet pipe 35, where it merges with the balance water and passes through the partition plate 34 to the entire upper layer 32 made of a strongly basic anion exchange resin. It is passed through ascending flow. With this liquid flow, the upper layer 32 rises and comes into contact with the third partition plate 37. If the alkali regenerator is continuously passed in this state, the strongly basic anion exchange resin is efficiently regenerated by the alkali regenerator, and the alkali regeneration waste liquid at this time is discharged from the second outflow pipe 31C. After the counter-current regeneration of the strongly basic anion exchange resin, the supply of the alkali regenerant is stopped, and pure water is flowed upward from only the bottom of the tower, and the strongly basic anion exchange resin in the upper layer 32 is washed. After that, the water flow process and the regeneration process are repeated without performing a backwash operation, and the raw water is treated by an ion exchange reaction to produce pure water.
[0053]
Therefore, according to this embodiment, the effect of the downward flowing water and the upward flow regeneration of the ion exchange tower 10 shown in FIG. 1 and the effect of the flow order of both ion exchange resin layers of the ion exchange tower 20 shown in FIG. Can be expected.
[0054]
The ion exchange tower 30A shown in FIG. 6 includes a fourth partition plate 38 provided below the partition plate 34 in the vicinity of the center in the longitudinal direction of the tower body 31 in the ion exchange tower 30 shown in FIG. An entrance / exit pipe 35 is arranged in the space between the partition plates 34 and 38, and is configured in the same manner as the ion exchange tower 30 shown in FIG. 5 except that there is a gap between the fourth partition plate 38 and the strongly acidic cation exchange resin of the lower layer 33. Has been. And also in this ion exchange tower 30A, ion exchange is performed by downward circulation water and upward flow regeneration similarly to the ion exchange tower 30 shown in FIG.
[0055]
Therefore, according to this embodiment, since the inlet / outlet pipe 35 is disposed in the space between the partition plates 34 and 38 and is isolated from the upper and lower ion exchange resin layers 32 and 33, countercurrent regeneration is performed later in the regeneration process. The strong acid cation exchange resin of the lower layer 33 is not reversely regenerated by the alkali regenerating agent, and the ion exchange capacity of the strongly acidic cation exchange resin of the lower layer 33 is increased by the amount not causing the reverse regeneration portion. In addition, also in the present embodiment, an effect similar to that of the ion exchange tower 30 shown in FIG. 5 can be expected.
[0056]
In the ion exchange tower 30B shown in FIG. 7, the partition plate 34 in the vicinity of the center in the longitudinal direction of the tower main body 31 in the ion exchange tower 30 shown in FIG. 5 is omitted, and the upper layer 32 and the lower layer 33 are directly laminated. The ion exchange column 30 is configured in the same manner as the ion exchange tower 30 shown in FIG. In the ion exchange tower 30B, as in the ion exchange tower 30 shown in FIG. 5, ion exchange is performed by descending circulating water and upward flow regeneration. Therefore, according to the present embodiment, the strong base anion exchange resin of the upper layer 32 and the strongly acidic cation exchange resin of the lower layer 33 are only partitioned by the specific gravity difference, so that both are present at the interface of both ion exchange resin layers. The portion above the inlet / outlet pipe 35 of the strongly acidic cation exchange resin in the lower layer 33 is reversely regenerated by the alkali regenerator when the strong base anion exchange resin is regenerated later. Since it is sometimes located upstream, the ion exchange capacity of the strongly acidic cation exchange resin is reduced, but it does not affect the quality of the treated water. Also in the present embodiment, it is possible to expect an effect similar to that of the ion exchange tower 30 shown in FIG.
[0057]
In the present invention, the basic operation is to carry out the water flow and regeneration with the strong acid cation exchange resin laminated in the upper layer or the lower layer and the strong base anion exchange resin in the upper layer or the lower layer and maintaining this lamination. However, there are a case where the strongly acidic cation exchange resin and the strongly basic anion exchange resin are divided by the partition plate, and a case where both the ion exchange resins are directly laminated without being divided by the partition plate. However, when the strong acid cation exchange resin is filled in the upper layer and the strong base anion exchange resin is filled in the lower layer, the specific gravity of the strong acid cation exchange resin is larger than the specific gravity of the strong base anion exchange resin. Although not carried out, strongly acidic cation exchange resin particles gradually invade into the strongly basic anion exchange resin layer by repeating water flow and regeneration in the opposite direction to each other and tend to reduce the purity of the treated water. . Therefore, in the case of such lamination filling, it is preferable to divide both ion exchange resins with a partition plate. On the other hand, as shown in FIG. 7 and the like, when the strong base anion exchange resin is laminated as an upper layer, the upper layer strongly basic anion exchange resin particles are still in the lower layer strongly acidic cation exchange resin even if water flow and regeneration are repeated. Since it is difficult to enter the layer, installation of the partition plate can be omitted.
[0058]
The ion exchange tower 40 shown in FIG. 8 is different from the case of the ion exchange tower 20 shown in FIG. 3 in that the vertical relationship between the strongly acidic cation exchange resin layer and the strongly basic anion exchange resin layer is reversed and each ion exchange resin. The regenerant is supplied and discharged at different positions so as to perform upflow circulation and countercurrent regeneration of downflow regeneration. Except for these points, the configuration is the same as that of the ion exchange column 20 shown in FIG. Therefore, each constituent member is the same as or equivalent to each constituent member of the ion exchange tower 20 shown in FIG.
[0059]
Next, an ion exchange method according to the present invention using the ion exchange tower 40 will be described. When raw water is treated in the water flow process, the raw water flows up into the tower main body 41 from the inflow pipe 41A at the bottom of the tower and passes through the second partition plate 46 over the entire lower surface of the lower layer 43 made of a strongly acidic cation exchange resin. scatter. The lower layer 43 is moved by a piston due to the feed pressure of the raw water to come into contact with the partition plate 44 to form a fixed layer. In this state, cations such as calcium ions, magnesium ions and sodium ions in the raw water pass while the raw water passes through. It is removed by a strongly acidic cation exchange resin. Thereafter, the raw water is dispersed on the entire lower surface of the upper layer 42 made of a strongly basic anion exchange resin through the partition plate 44, and the upper layer 42 moves in the same manner as the lower layer 43 to come into contact with the third partition plate 47 to form the fixed layer. In this state, while the treated water after removal of the anion is passed, the anion such as sulfate ion and chloride ion and silica are removed by the strongly basic anion exchange resin. This treated water flows out from the outflow pipe 41B as high-purity pure water via the third partition plate 47 and is supplied to the next step.
[0060]
When each ion exchange resin reaches the flow-through point due to the raw water treatment, each ion exchange resin is regenerated in a regeneration step. For this purpose, first, the strongly basic anion exchange resin of the upper layer 42 located on the water outlet side is regenerated countercurrently without backwashing each ion exchange resin layer. That is, as an alkali regenerator, for example, an aqueous sodium hydroxide solution is supplied in a downward flow from the second inflow pipe 41D at the top of the tower, and balance water is supplied in an upward flow from the bottom of the tower into the tower body 42. As a result, the alkali regenerant is dispersed throughout the upper layer 42 via the second partition plate 47, and the alkali regenerant passes through the entire upper layer 42 in a downward flow. During this flow, the strongly basic anion exchange resin is regenerated. Is done. During this time, since the balance water is passed in ascending flow from the bottom of the tower, the alkaline water is prevented from entering the lower layer 43 by the balance water. Then, the alkali regeneration waste liquid merges with the balance water in the inlet / outlet pipe 45 and is discharged from the external pipe 45A. After countercurrent regeneration of the strongly basic anion exchange resin in the upper layer 42, pure water is supplied from the top of the tower instead of the alkali regenerant, and water is passed from both the top and the bottom of the tower body 41 to strengthen the upper layer 42. The basic anion exchange resin is washed, and the washing waste liquid is discharged from the inlet / outlet pipe 45 and the outer pipe 45A.
[0061]
After the washing operation of the upper layer, the strongly acidic cation exchange resin of the lower layer 43 located on the water inlet side is regenerated countercurrently. That is, for example, an aqueous hydrochloric acid solution is supplied as an acid regenerant in a downward flow from the external pipe 45A in the straight body portion, and balance water is supplied in a downward flow from the top of the tower. As a result, the acid regenerant flows into the lowermost part of the upper layer 42 from the inlet / outlet pipe 45, joins with the balance water, and passes through the partition plate 44 to the entire strongly acidic cation exchange resin of the lower layer 43 in a downward flow. While the acid regenerant passes through the lower layer 43, the strongly acidic cation exchange resin is efficiently regenerated. When the counter-current regeneration operation of the strong acid cation exchange resin is completed, pure water is continuously flowed down from only the top of the tower, the strong acid cation exchange resin in the lower layer 43 is washed, and the regeneration operation is terminated. After that, the water flow process and the regeneration process are repeated without performing a backwash operation, and the raw water is treated by an ion exchange reaction to produce pure water.
[0062]
Therefore, according to the present embodiment, the effect of the upward circulation water and the downward flow regeneration of the ion exchange tower 20 shown in FIG. 3 and the effect of the water flow order of both ion exchange resin layers of the ion exchange tower 10 shown in FIG. Can be expected.
[0063]
The ion exchange tower 40A shown in FIG. 9 is provided with a fourth partition plate 48 via a space below the partition plate 44 in the vicinity of the center of the column body 41 in the ion exchange tower 40 shown in FIG. Except for the fact that an inlet / outlet pipe 45 is disposed in the space between the partition plates 44 and 48 and there is a gap between the fourth partition plate 48 and the strong acid cation exchange resin of the lower layer 43, the same as the ion exchange tower 40 shown in FIG. It is configured. In the ion exchange tower 40A, as in the ion exchange tower 40 shown in FIG. 8, ion exchange is performed by ascending circulating water and descending flow regeneration.
[0064]
Therefore, according to this embodiment, since the inlet / outlet pipe 45 is disposed in the space between the partition plates 44 and 48 and is isolated from the upper and lower ion exchange resin layers 42 and 43, countercurrent regeneration is performed later in the regeneration process. The strong basic anion exchange resin of the upper layer 42 is not reversely regenerated by the acid regenerating agent, and the ion exchange capacity of the strong basic anion exchange resin of the upper layer 42 is increased by the amount that does not generate the reverse regenerated portion. In addition, also in the present embodiment, an effect similar to that of the ion exchange tower 40 shown in FIG. 8 can be expected.
[0065]
The ion exchange tower 40B shown in FIG. 10 is the same as that shown in FIG. 8, except that the partition plate near the longitudinal center of the tower body in the ion exchange tower 40 shown in FIG. 8 is omitted and the upper layer 42 and the lower layer 43 are directly laminated. It is comprised similarly to the ion exchange tower 40 shown. In the ion exchange tower 40B, as in the ion exchange tower 40 shown in FIG. 8, ion exchange is performed by ascending circulating water and descending flow regeneration. Therefore, according to the present embodiment, the strong base anion exchange resin of the upper layer 42 and the strong acid cation exchange resin of the lower layer 43 are only partitioned by the specific gravity difference, so that both are present at the interface of both ion exchange resin layers. When the strong acid cation exchange resin is mixed slightly afterward, the portion of the upper layer 42 below the inlet / outlet tube 45 of the strongly basic anion exchange resin is reversely regenerated by the acid regenerant. Since it is sometimes located on the upstream side, the ion exchange capacity of the strongly basic anion exchange resin is reduced, but it does not affect the quality of the treated water. Also in the present embodiment, it is possible to expect an effect similar to that of the ion exchange tower 40 shown in FIG.
[0066]
FIG. 11 shows a diagram in which, for example, the ion exchange tower 20 shown in FIG. 3 is applied to a pure water production apparatus as described above. In the case of this pure water production apparatus, the ion exchange tower 20 is disposed on the downstream side of the reverse osmosis membrane device 50, and fine particles in the raw water are removed by the reverse osmosis membrane device 50, and most of the hardness component is removed. The permeated water is configured to flow into the ion exchange tower 20. By disposing the ion exchange tower 20 on the downstream side of the reverse osmosis membrane device 50 in this way, the ion exchange resin layer does not increase in pressure loss due to accumulation of fine particles, and further, a strongly basic anion exchange resin. Magnesium hydroxide or the like is not generated in the layer, and stable operation can be performed over a long period of time.
[0067]
In addition, although not shown in figure, in processing the to-be-processed water containing calcium hydrogen carbonate or magnesium hydrogen carbonate, after processing to-be-processed water first with the dealkalization softening device which combined the weakly acidic cation exchange resin and the decarbonation tower. It can also be processed in each ion exchange column of the present invention. When the water to be treated is passed through an H-type weakly acidic cation exchange resin, calcium ions and magnesium ions corresponding to the bicarbonate ions are ion-exchanged, and the bicarbonate ions become free carbonates. Therefore, most of the free carbonic acid can be removed by treating it with a decarboxylation tower. By adopting such a treatment method, hydrogen carbonate ions can be removed from the ion load of the ion exchange tower of the present invention, and pure water can be obtained at a lower cost. In addition, since the weakly acidic cation exchange resin has a good regeneration efficiency, a regeneration waste solution obtained by regenerating the strongly acidic cation exchange resin in the ion exchange tower of the present invention can be used for the regeneration.
[0068]
Further, when, for example, two ion exchange towers used in the present invention are installed, the use efficiency of each ion exchange resin can be increased by operating by the merry-go-round method, and pure water can be produced continuously and efficiently.
[0069]
In addition, although what demonstrated the ion-exchange tower 20 arrange | positioning in the downstream of the reverse osmosis membrane apparatus 50 was demonstrated in FIG. 11, other ion-exchange towers shown in FIGS. 2-10 similarly produce the pure water shown in FIG. It can be applied to the device.
[0070]
【The invention's effect】
As described above, according to the first to eleventh aspects of the present invention, the following various effects can be achieved.
(1) Since a strongly acidic cation exchange resin and a strongly basic cation exchange resin are packed in one tower, the number of towers can be minimized, the ion exchange apparatus can be made compact, and the installation cost and installation area can be reduced. It can be greatly reduced.
(2) Even though both ion exchange resins are packed in one tower, without mixing both ion exchange resins as in the past, in order to perform water flow and regeneration while maintaining the laminated state of both ion exchange resins, In order to perform countercurrent regeneration without causing regeneration failure due to clamping phenomenon due to both ion exchange resins as occurs in conventional mixed bed ion exchangers, mixed bed ion exchangers for silica in treated water Rather better. That is, in the mixed bed type ion exchange apparatus, since the ion exchange resin is mixed after the regeneration, the silica-type strongly basic anion exchange resin remaining by the regeneration is dispersed and averaged in the entire resin layer, and the treated water is Silica leak is determined by this averaged silica-type fraction, but since the present invention is countercurrent regeneration, the outflow side of the treated water is completely regenerated and the silica leak is extremely small.
(3) When the laminated strong acid cation exchange resin and strong base anion exchange resin are regenerated, the regeneration operation itself is performed in an ideal state because countercurrent regeneration is performed without backwashing after passing water. It is possible to maximize the amount of H-type strongly acidic cation exchange resin or OH-type strongly basic anion exchange resin produced after regeneration per the amount of the regenerant used, and to increase the processing capacity.
(4) When regenerating the laminated ion exchange resin, when water is passed from the strongly acidic cation exchange resin to the strongly basic anion exchange resin, the strongly acidic cation exchange resin is regenerated after regenerating the strongly basic anion exchange resin. When the water is regenerated and water is passed from the strongly basic anion exchange resin to the strongly acidic cation exchange resin, both the ion exchange resins are coated such that the strong acid anion exchange resin is regenerated after the strong acid cation exchange resin is regenerated. By regenerating in the reverse order of passing the treated water, the regenerant of one ion exchange resin that is regenerated later is the other ion exchange that has been regenerated first. resin The salt form is located in the most upstream part even if it comes into contact with the salt, so that the purity of the treated water can be prevented from being affected at all.
(5) Even if water passage and regeneration are repeatedly performed by partitioning both ion exchange resins with a partition plate, stable ion exchange operation can be performed without mixing both ion exchange resins.
(6) A pressure loss of the ion exchange resin layer due to accumulation of fine particles by a flow in which a reverse osmosis membrane device is installed, water to be treated is treated by the reverse osmosis membrane device, and the permeate is treated by the ion exchange tower used in the present invention. In addition, it is possible to prevent precipitation such as magnesium hydroxide in the strong basic anion exchange resin layer even when the strong basic anion exchange resin is contacted first. And high-purity treated water can be obtained.
[Brief description of the drawings]
FIG. 1 is a block diagram showing an embodiment of an ion exchange column suitably used in the ion exchange method of the present invention.
FIG. 2 is a configuration diagram showing another embodiment of an ion exchange column preferably used in the ion exchange method of the present invention.
FIG. 3 is a block diagram showing still another embodiment of an ion exchange column suitably used in the ion exchange method of the present invention.
FIG. 4 is a configuration diagram showing still another embodiment of an ion exchange column preferably used in the ion exchange method of the present invention.
FIG. 5 is a configuration diagram showing still another embodiment of an ion exchange column preferably used in the ion exchange method of the present invention.
FIG. 6 is a configuration diagram showing still another embodiment of an ion exchange column preferably used in the ion exchange method of the present invention.
FIG. 7 is a configuration diagram showing still another embodiment of an ion exchange column suitably used in the ion exchange method of the present invention.
FIG. 8 is a configuration diagram showing still another embodiment of an ion exchange column suitably used in the ion exchange method of the present invention.
FIG. 9 is a block diagram showing still another embodiment of an ion exchange column suitably used in the ion exchange method of the present invention.
FIG. 10 is a configuration diagram showing still another embodiment of an ion exchange column suitably used in the ion exchange method of the present invention.
FIG. 11 is a flowchart showing the main part of a pure water production apparatus to which the ion exchange tower shown in FIG. 1 is applied.
[Explanation of symbols]
10, 20, 30, 40 Ion exchange tower
10A, 20A, 30A, 40A ion exchange tower
11, 21, 31, 41 Tower body
12, 22, 32, 42 Upper layer (ion exchange resin layer)
13, 23, 33, 43 Lower layer (ion exchange resin layer)
14, 24, 34, 44 Partition plate
15, 25, 35, 45 Access pipe
18, 28, 38, 48 Third partition plate
30B, 40B ion exchange tower

Claims (11)

同一塔内に形成された強酸性カチオン交換樹脂層と強塩基性アニオン交換樹脂層の各層に被処理水を通水する通水工程と、上記各イオン交換樹脂層にそれぞれの再生剤を通液する操作を含む再生工程とを有し、上記通水工程と上記再生工程を交互に行うイオン交換方法であって、上記通水工程では両イオン交換樹脂の積層状態を維持したまま被処理水を両イオン交換樹脂層の一方のイオン交換樹脂層に通水した後、他方のイオン交換樹脂層に通水し、上記再生工程では、上記両イオン交換樹脂の逆洗操作を行うことなく、上記各イオン交換樹脂層に上記被処理水の通水方向とは逆の方向にそれぞれの再生剤を通液すると共に上記両イオン交換樹脂に被処理水を通水する順序と逆の順序で上記両イオン交換樹脂を再生することを特徴とするイオン交換方法。A water passing step for passing water to be treated to each of the strongly acidic cation exchange resin layer and the strongly basic anion exchange resin layer formed in the same tower, and the respective regenerants through each of the ion exchange resin layers. An ion exchange method in which the water flow step and the regeneration step are alternately performed, and in the water flow step, the water to be treated is maintained while maintaining a laminated state of both ion exchange resins. After passing water through one ion exchange resin layer of both ion exchange resin layers, water is passed through the other ion exchange resin layer, and in the regeneration step, each of the above ion exchange resins is performed without performing a backwash operation. The regenerating agent is passed through the ion exchange resin layer in a direction opposite to the direction of water flow of the treated water, and the both ions are flowed in the reverse order of the flow of the treated water through the ion exchange resins. Io, characterized in that for reproducing exchange resin How to replace. 同一塔内で上層として形成された強酸性カチオン交換樹脂層と下層として形成された強塩基性アニオン交換樹脂層に被処理水を上層から下層へ下降流で通水する通水工程と、上記各イオン交換樹脂層にそれぞれの再生剤を上昇流で通液する操作を含む再生工程とを有し、上記通水工程と上記再生工程を交互に行うイオン交換方法であって、上記通水工程終了後の上記再生工程では、上記両イオン交換樹脂の逆洗操作を行うことなく、先に下層の強塩基性アニオン交換樹脂にその再生剤を通液し、その後に上層の強酸性カチオン交換樹脂にその再生剤を通液することを特徴とするイオン交換方法。A water passing step of passing water to be treated in a downward flow from the upper layer to the lower layer through a strongly acidic cation exchange resin layer formed as an upper layer and a strongly basic anion exchange resin layer formed as a lower layer in the same tower; A regeneration step including an operation of passing each regenerant in an upward flow through the ion exchange resin layer, wherein the water flow step and the regeneration step are alternately performed, wherein the water flow step ends. In the subsequent regeneration step, the regenerant is passed through the lower strong base anion exchange resin without performing backwashing of the both ion exchange resins, and then the upper strong acid cation exchange resin. An ion exchange method characterized by passing the regenerant. 同一塔内で上層として形成された強酸性カチオン交換樹脂層と下層として形成された強塩基性アニオン交換樹脂層に被処理水を下層から上層へ上昇流で通水する通水工程と、上記各イオン交換樹脂層にそれぞれの再生剤を下降流で通液する操作を含む再生工程とを有し、上記通水工程と上記再生工程を交互に行うイオン交換方法であって、上記通水工程終了後の上記再生工程では、上記両イオン交換樹脂の逆洗操作を行うことなく、先に上層の強酸性カチオン交換樹脂にその再生剤を通液し、その後に下層の強塩基性アニオン交換樹脂にその再生剤を通液することを特徴とするイオン交換方法。A water passing step of passing water to be treated in an upward flow from the lower layer to the upper layer through the strongly acidic cation exchange resin layer formed as the upper layer and the strongly basic anion exchange resin layer formed as the lower layer in the same tower; A regeneration step including an operation of passing each regenerant in a downward flow through the ion exchange resin layer, and an ion exchange method for alternately performing the water flow step and the regeneration step, wherein the water flow step ends. In the subsequent regeneration step, the regenerant is first passed through the strong acidic cation exchange resin in the upper layer without performing the back washing operation of the both ion exchange resins, and then the strong basic anion exchange resin in the lower layer. An ion exchange method characterized by passing the regenerant. 同一塔内で上層として形成された強塩基性アニオン交換樹脂層と下層として形成された強酸性カチオン交換樹脂層に被処理水を上層から下層へ下降流で通水する通水工程と、上記各イオン交換樹脂層にそれぞれの再生剤を上昇流で通液する操作を含む再生工程とを有し、上記通水工程と上記再生工程を交互に行うイオン交換方法であって、上記通水工程終了後の上記再生工程では、上記両イオン交換樹脂層の逆洗操作を行うことなく、先に下層の強酸性カチオン交換樹脂にその再生剤を通液し、その後に上層の強塩基性アニオン交換樹脂層にその再生剤を通液することを特徴とするイオン交換方法。A water passing step of passing water to be treated in a downward flow from the upper layer to the lower layer through a strongly basic anion exchange resin layer formed as an upper layer and a strongly acidic cation exchange resin layer formed as a lower layer in the same tower; A regeneration step including an operation of passing each regenerant in an upward flow through the ion exchange resin layer, wherein the water flow step and the regeneration step are alternately performed, wherein the water flow step ends. In the subsequent regeneration step, the regenerant is first passed through the strongly acidic cation exchange resin in the lower layer without backwashing the both ion exchange resin layers, and then the strongly basic anion exchange resin in the upper layer. An ion exchange method characterized by passing the regenerant through a layer. 同一塔内で上層として形成された強塩基性アニオン交換樹脂層と下層として形成された強酸性カチオン交換樹脂層に被処理水を下層から上層へ上昇流で通水する通水工程と、上記各両イオン交換樹脂層にそれぞれの再生剤を下降流で通液する操作を含む再生工程とを有し、上記通水工程と上記再生工程を交互に行うイオン交換方法であって、上記通水工程終了後の上記再生工程では、両イオン交換樹脂層の逆洗操作を行うことなく、先に上層の強塩基性アニオン交換樹脂にその再生剤を通液し、その後に下層の強酸性カチオン交換樹脂にその再生剤を通液することを特徴とするイオン交換方法。A water passing step of passing water to be treated in an upward flow from the lower layer to the upper layer through the strongly basic anion exchange resin layer formed as the upper layer and the strongly acidic cation exchange resin layer formed as the lower layer in the same tower; A regenerating process including an operation of passing each regenerant in a downward flow through both ion exchange resin layers, wherein the water passing process and the regenerating process are performed alternately, the water passing process In the above regeneration step after completion, the regenerant is first passed through the upper strong basic anion exchange resin without backwashing both ion exchange resin layers, and then the strongly acidic cation exchange resin in the lower layer. An ion exchange method characterized in that the regenerant is passed through. 上記被処理水として予め逆浸透膜装置により処理した透過水を用いることを特徴とする請求項１〜請求項５のいずれか１項に記載のイオン交換方法。The ion exchange method according to any one of claims 1 to 5 , wherein permeated water previously treated by a reverse osmosis membrane device is used as the water to be treated. 同一塔内で上層として形成された強酸性カチオン交換樹脂層と下層として形成された強塩基性アニオン交換樹脂層に被処理水を上層から下層へ下降流で通水する通水工程と、上記各イオン交換樹脂層にそれぞれの再生剤を上昇流で通液する操作を含む再生工程とを有し、上記通水工程と上記再生工程を交互に行う際に、上記通水工程終了後の上記再生工程では、上記両イオン交換樹脂の逆洗操作を行うことなく、先に下層の強塩基性アニオン交換樹脂にその再生剤を通液し、その後に上層の強酸性カチオン交換樹脂にその再生剤を通液する下降流通水、上昇流再生によるイオン交換方法に用いられるイオン交換塔であって、上層の強酸性カチオン交換樹脂層と下層の強塩基性アニオン交換樹脂層を仕切る仕切板を塔内に横方向に設けると共に上記仕切板の下方近傍に再生剤の出入管を設け、且つ、上記仕切板は被処理水の流通を許すが、上記各イオン交換樹脂の流通を阻止するように構成されたことを特徴とするイオン交換塔。 A water passing step for passing water to be treated in a downward flow from the upper layer to the lower layer through the strongly acidic cation exchange resin layer formed as the upper layer and the strongly basic anion exchange resin layer formed as the lower layer in the same tower; A regeneration step including an operation of passing each regenerant in an upward flow through the ion exchange resin layer, and the regeneration after completion of the water flow step when the water flow step and the regeneration step are alternately performed. In the process, without performing the back-washing operation of the both ion exchange resins, the regenerant is first passed through the strongly basic anion exchange resin in the lower layer, and then the regenerant is added to the strongly acidic cation exchange resin in the upper layer. An ion exchange tower used in an ion exchange method by flowing downward flowing water and upward flow regeneration, and a partition plate separating the upper strong acid cation exchange resin layer and the lower strong base anion exchange resin layer in the tower While providing in the horizontal direction An inlet / outlet pipe for the regenerant is provided in the vicinity of the lower part of the partition plate, and the partition plate allows the flow of the water to be treated, but is configured to prevent the flow of each ion exchange resin. Ion exchange tower. 同一塔内で上層として形成された強酸性カチオン交換樹脂層と下層として形成された強塩基性アニオン交換樹脂層に被処理水を下層から上層へ上昇流で通水する通水工程と、上記各イオン交換樹脂層にそれぞれの再生剤を下降流で通液する操作を含む再生工程とを有し、上記通水工程と上記再生工程を交互に行う際に、上記通水工程終了後の上記再生工程では、上記両イオン交換樹脂の逆洗操作を行うことなく、先に上層の強酸性カチオン交換樹脂にその再生剤を通液し、その後に下層の強塩基性アニオン交換樹脂にその再生剤を通液する上昇流通水、下降流再生によるイオン交換方法に用いられるイオン交換塔であって、上層の強酸性カチオン交換樹脂層と下層の強塩基性アニオン交換樹脂層を仕切る仕切板を塔内に横方向に設けると共に上記仕切板の上方近傍に再生剤の出入管を設け、且つ、上記仕切板は被処理水の流通を許すが、上記各イオン交換樹脂の流通を阻止するように構成されたことを特徴とするイオン交換塔。 A water passing step of passing water to be treated in an upward flow from the lower layer to the upper layer through the strongly acidic cation exchange resin layer formed as the upper layer and the strongly basic anion exchange resin layer formed as the lower layer in the same tower; A regeneration step including an operation of passing each regenerant in a downward flow through the ion exchange resin layer, and the regeneration after completion of the water flow step when the water flow step and the regeneration step are alternately performed. In the process, without performing the back washing operation of the both ion exchange resins, the regenerant is first passed through the strong acidic cation exchange resin in the upper layer, and then the regenerant is added to the strongly basic anion exchange resin in the lower layer. An ion exchange column used in an ion exchange method by flowing upward flowing water and downward flow regeneration, and a partition plate for partitioning an upper strong acid cation exchange resin layer and a lower strong base anion exchange resin layer in the tower While providing in the horizontal direction An inlet / outlet pipe for the regenerant is provided in the vicinity of the upper part of the partition plate, and the partition plate allows the flow of the water to be treated, but is configured to prevent the flow of each ion exchange resin. Ion exchange tower. 同一塔内で上層として形成された強塩基性アニオン交換樹脂層と下層として形成された強酸性カチオン交換樹脂層に被処理水を上層から下層へ下降流で通水する通水工程と、上記各イオン交換樹脂層にそれぞれの再生剤を上昇流で通液する操作を含む再生工程とを有し、上記通水工程と上記再生工程を交互に行う際に、上記通水工程終了後の上記再生工程では、上記両イオン交換樹脂層の逆洗操作を行うことなく、先に下層の強酸性カチオン交換樹脂にその再生剤を通液し、その後に上層の強塩基性アニオン交換樹脂層にその再生剤を通液する下降流通水、上昇流再生によるイオン交換方法に用いられるイオン交換塔であって、上層の強塩基性アニオン交換樹脂層と下層の強酸性カチオン交換樹脂層を被処理水の流通を許すが、上記各イオン交換樹脂の流通を阻止する仕切板により仕切り、あるいは仕切板により仕切ることなく、更に上記両イオン交換樹脂層の分離境界面または上記仕切板の下方近傍に再生剤の出入管を設けたことを特徴とするイオン交換塔。 A water passing step of passing the water to be treated in a downward flow from the upper layer to the lower layer through a strongly basic anion exchange resin layer formed as an upper layer and a strongly acidic cation exchange resin layer formed as a lower layer in the same tower; A regeneration step including an operation of passing each regenerant in an upward flow through the ion exchange resin layer, and the regeneration after completion of the water flow step when the water flow step and the regeneration step are alternately performed. In the process, the regenerant is first passed through the strongly acidic cation exchange resin in the lower layer without performing the back washing operation of the both ion exchange resin layers, and then the regeneration is performed in the strongly basic anion exchange resin layer in the upper layer. Downflow water flowing through the agent, ion exchange tower used in ion exchange method by upflow regeneration, circulation of water to be treated between upper strong basic anion exchange resin layer and lower strong acid cation exchange resin layer Allow each of the above ions Partitioning with a partition plate that prevents the flow of the exchange resin, or without partitioning with the partition plate, a separation agent interface between the ion exchange resin layers or a lower part of the partition plate is provided with a regenerant inlet / outlet pipe. An ion exchange tower. 同一塔内で上層として形成された強塩基性アニオン交換樹脂層と下層として形成された強酸性カチオン交換樹脂層に被処理水を下層から上層へ上昇流で通水する通水工程と、上記各両イオン交換樹脂層にそれぞれの再生剤を下降流で通液する操作を含む再生工程とを有し、上記通水工程と上記再生工程を交互に行う際に、上記通水工程終了後の上記再生工程では、両イオン交換樹脂層の逆洗操作を行うことなく、先に上層の強塩基性アニオン交換樹脂にその再生剤を通液し、その後に下層の強酸性カチオン交換樹脂にその再生剤を通液する上昇流通水、下降流再生によるイオン交換方法に用いられるイオン交換塔であって、上層の強塩基性アニオン交換樹脂層と下層の強酸性カチオン交換樹脂層を被処理水の流通を許すが、上記各イオン交換樹脂の流通を阻止する仕切板により仕切り、あるいは仕切板により仕切ることなく、更に上記両イオン交換樹脂層の分離境界面または上記仕切板の上方近傍に再生剤の出入管を設けたことを特徴とするイオン交換塔。 A water passing step of passing water to be treated in an upward flow from the lower layer to the upper layer through the strongly basic anion exchange resin layer formed as the upper layer and the strongly acidic cation exchange resin layer formed as the lower layer in the same tower; A regeneration step including an operation of passing the respective regenerant in a downward flow through both ion exchange resin layers, and when the water flow step and the regeneration step are alternately performed, In the regeneration step, the regenerant is first passed through the strong base anion exchange resin in the upper layer without backwashing the both ion exchange resin layers, and then the regenerant into the strongly acidic cation exchange resin in the lower layer. This is an ion exchange tower used in the ion exchange method by recirculating upflow and downflow regeneration, and it is possible to distribute the treated water through the upper strong basic anion exchange resin layer and lower strong acid cation exchange resin layer. Forgive each ion exchange above Partitioning with a partition plate that prevents the flow of fat, or without partitioning with a partition plate, a regenerant inlet / outlet pipe is provided on the separation boundary surface of the both ion exchange resin layers or near the upper portion of the partition plate. Ion exchange tower. 同一塔内に形成された強酸性カチオン交換樹脂層と強塩基性アニオン交換樹脂層の各層に被処理水を通水する通水工程と、上記各イオン交換樹脂層にそれぞれの再生剤を通液する操作を含む再生工程とを有し、上記通水工程と上記再生工程を交互に行う際に、上記通水工程では両イオン交換樹脂の積層状態を維持したまま被処理水を両イオン交換樹脂層の一方のイオン交換樹脂層に通水した後、他方のイオン交換樹脂層に通水し、上記再生工程では、上記両イオン交換樹脂の逆洗操作を行うことなく、上記各イオン交換樹脂層に上記被処理水の通水方向とは逆の方向にそれぞれの再生剤を通液すると共に上記両イオン交換樹脂に被処理水を通水する順序と逆の順序で上記両イオン交換樹脂を再生するイオン交換方法に用いられるイオン交換塔であって、強酸性カチオン交換樹脂層と強塩基性アニオン交換樹脂層とを仕切る上下２段の仕切板を空間を介して塔内に横方向にそれぞれ設けると共に上記両仕切板間の空間に上記各再生剤の出入管を設け、これら両仕切板は被処理水の流通を許すが、上記各イオン交換樹脂の流通を阻止するように構成されたことを特徴とするイオン交換塔。 A water passing step for passing water to be treated to each of the strongly acidic cation exchange resin layer and the strongly basic anion exchange resin layer formed in the same tower, and the respective regenerants through each of the ion exchange resin layers. A regenerating step including an operation to perform the water flow step and the regenerating step alternately. In the water passing step, the water to be treated is treated with both ion exchange resins while maintaining the laminated state of both ion exchange resins. After passing through one ion exchange resin layer of the layer, the other ion exchange resin layer is passed through, and in the regeneration step, each of the ion exchange resin layers is performed without performing a backwash operation of the both ion exchange resins. In addition, the respective regenerants are passed in the direction opposite to the direction in which the water to be treated is passed, and the ion exchange resins are regenerated in the reverse order to the order in which the water to be treated is passed through the both ion exchange resins. ion exchange column to be used in the ion exchange method to And two upper and lower partition plates for partitioning the strongly acidic cation exchange resin layer and the strongly basic anion exchange resin layer are provided in the tower in the horizontal direction through the space, and each of the partition plates is provided in the space between the partition plates. An ion exchange tower characterized in that a regenerant inlet / outlet pipe is provided, and both the partition plates allow the water to be treated to flow but prevent the flow of the respective ion exchange resins.
JP31150396A 1996-11-07 1996-11-07 Ion exchange method and ion exchange column used in this ion exchange method Expired - Lifetime JP3632331B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP31150396A JP3632331B2 (en) 1996-11-07 1996-11-07 Ion exchange method and ion exchange column used in this ion exchange method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP31150396A JP3632331B2 (en) 1996-11-07 1996-11-07 Ion exchange method and ion exchange column used in this ion exchange method

Publications (2)

Publication Number Publication Date
JPH10137751A JPH10137751A (en) 1998-05-26
JP3632331B2 true JP3632331B2 (en) 2005-03-23

Family

ID=18018026

Family Applications (1)

Application Number Title Priority Date Filing Date
JP31150396A Expired - Lifetime JP3632331B2 (en) 1996-11-07 1996-11-07 Ion exchange method and ion exchange column used in this ion exchange method

Country Status (1)

Country Link
JP (1) JP3632331B2 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105000632A (en) * 2015-08-05 2015-10-28 华北电力科学研究院有限责任公司 Trace-amount and high-purity water preparation device and method

Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19956963B4 (en) * 1999-11-18 2005-12-29 Gkss-Forschungszentrum Geesthacht Gmbh Means for connecting at least two adjacent at least in the connection area workpieces by the method of friction stir welding
JP4931178B2 (en) 2005-10-06 2012-05-16 株式会社荏原製作所 Condensate desalination method and apparatus
JP4869881B2 (en) * 2006-11-21 2012-02-08 野村マイクロ・サイエンス株式会社 Ion exchange apparatus and ion exchange method
JP5235091B2 (en) * 2008-04-07 2013-07-10 オルガノ株式会社 Method and apparatus for removing aldehyde compound from alcohol-containing liquid
CN102548906A (en) * 2009-09-30 2012-07-04 栗田工业株式会社 Ion-exchange device, column therefor, and water treatment device
JP5609181B2 (en) * 2010-03-16 2014-10-22 栗田工業株式会社 Ion exchanger
JP5720364B2 (en) * 2011-03-29 2015-05-20 栗田工業株式会社 Ion exchanger
JP5849419B2 (en) * 2011-03-29 2016-01-27 栗田工業株式会社 Pure water production equipment
CN104961193B (en) * 2015-07-19 2017-03-22 长春黄金研究院 Separation method of zinc cyanide complex ions
JP6983582B2 (en) * 2017-08-30 2021-12-17 オルガノ株式会社 Cartridge for water purifier and water purifier for softening

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105000632A (en) * 2015-08-05 2015-10-28 华北电力科学研究院有限责任公司 Trace-amount and high-purity water preparation device and method

Also Published As

Publication number Publication date
JPH10137751A (en) 1998-05-26

Similar Documents

Publication Publication Date Title
JP4869881B2 (en) Ion exchange apparatus and ion exchange method
US3382169A (en) Process for deionizing aqueous solutions
US4648976A (en) Integral water demineralizer system and method
JP3632331B2 (en) Ion exchange method and ion exchange column used in this ion exchange method
US3711401A (en) Regeneration method for dual beds of ion exchange resins
US6362240B2 (en) Mixed-bed type sugar solution refining system and regeneration method for such apparatus
US2841550A (en) Process of operating a demineralizing installation
WO2007040266A1 (en) Process and equipment for demineralizing condensate
JP2001205263A (en) Double bed type ion exchange apparatus
JP3632343B2 (en) Pure water production method and ion exchange tower
US4379855A (en) Method of ion exchange regeneration
JP2940651B2 (en) Pure water production equipment
JP2002361247A (en) Method for manufacturing pure water
JP3913379B2 (en) Regeneration method of mixed bed type ion exchange equipment
JP2576155B2 (en) Multi-layer ion exchanger
JP2607544B2 (en) Ion exchange tower used for upflow regeneration
JP3963032B2 (en) Ion exchange device and polishing filter
JP2742975B2 (en) Regeneration method of ion exchange device
JP2940648B2 (en) Pure water production equipment
JP4797304B2 (en) Pure water production equipment
CN1107808A (en) Regeneration method for double-layer bed in salt removing system for water treatment
JP3570066B2 (en) Ion exchange equipment
JP2941121B2 (en) Ultrapure water production equipment
JP3458317B2 (en) Ion exchange apparatus and method for regenerating ion exchange resin
JP4356987B2 (en) Condensate demineralization treatment method and apparatus and method for forming packed bed thereof

Legal Events

Date Code Title Description
A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20040217

A521 Written amendment

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20040416

TRDD Decision of grant or rejection written
A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

Effective date: 20041124

A61 First payment of annual fees (during grant procedure)

Free format text: JAPANESE INTERMEDIATE CODE: A61

Effective date: 20041213

R150 Certificate of patent or registration of utility model

Free format text: JAPANESE INTERMEDIATE CODE: R150

RVTR Cancellation due to determination of trial for invalidation
FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20080107

Year of fee payment: 3