JP3976128B2

JP3976128B2 - Method for improving water quality of desalination equipment

Info

Publication number: JP3976128B2
Application number: JP2002035490A
Authority: JP
Inventors: 正弘萩原; 丈志出水
Original assignee: Ebara Corp
Current assignee: Ebara Corp
Priority date: 2002-02-13
Filing date: 2002-02-13
Publication date: 2007-09-12
Anticipated expiration: 2022-02-13
Also published as: JP2003236540A

Description

【０００１】
【発明の属する技術分野】
本発明は、脱塩装置に使用するイオン交換樹脂について、樹脂粒子中に存在する潜在的欠陥を持った樹脂粒子を効率よく除去し、樹脂粒子を物理的に健全に維持し、処理水中への微細樹脂粒子や破砕樹脂粒子（粒子片も含む）の漏洩を無くし、処理水の水質向上を図るための脱塩装置の通水方法に関する。
【０００２】
【従来の技術】
脱塩装置にイオン交換樹脂粒子を充填して通水運転を行う場合、まず、充填する陽イオン交換樹脂粒子及び／又は陰イオン交換樹脂粒子を、脱塩塔又は再生塔に水と一緒に充填する。その後、塔内に収容したイオン交換樹脂粒子のレベルを上回るレベルまで水を張り、塔下部より空気を注入し、イオン交換樹脂粒子を撹拌し、樹脂粒子混合物中に存在する微細樹脂粒子及び破砕樹脂粒子を水中に遊離させる。次に、塔下部より逆洗水を注入し樹脂層を十分に展開させ、樹脂層上部に出てきた微細樹脂粒子や破砕樹脂粒子をオーバーフローさせて系外に排出させる。この操作を複数回繰り返し行い、樹脂層中の微細樹脂粒子及び破砕樹脂粒子を除去する。樹脂粒子を混合し脱塩塔に移送した後、脱塩塔の通水運転を開始する。なお、脱塩塔に樹脂粒子を直接充填する場合は、上述の操作を全て脱塩塔で実施し通水運転を開始する。
【０００３】
【発明が解決しようとする課題】
前述の脱塩装置にイオン交換樹脂を充填し通水運転に供する方法では、健全なイオン交換樹脂粒子中に混在する、内部歪みや微細亀裂などの潜在的欠陥を持つイオン交換樹脂粒子を、完全に除去することが出来ない。そのため、逆洗再生、通薬再生、これに付随する樹脂移送、採水運転等を継続的に続けて行くと、その過程の中で潜在的欠陥を持つイオン交換樹脂粒子が破砕する可能性が高い。これらの破砕樹脂粒子は、通常の逆洗再生では十分に取り除くことが難しく、通水運転中に樹脂層に加わる差圧や、脱塩塔投入時の過渡的な衝撃により下流側に漏洩して、処理水の悪化を招く恐れがある。
【０００４】
本発明は、このような実情に鑑みてなされたものであり、脱塩装置に使用するイオン交換樹脂粒子について、樹脂粒子中に存在する潜在的欠陥を持った樹脂粒子を効率的に除去し、樹脂粒子を物理的に健全に維持し、処理水中への微細樹脂粒子や破砕樹脂粒子の漏洩を無くし、処理水の水質向上を図るための脱塩装置の水質向上方法を提供するものである。
【０００５】
【課題を解決するための手段】
本発明者等は、前記目的を達成するため種々検討を行った結果、脱塩装置に使用する陽イオン交換樹脂粒子及び／又は陰イオン交換樹脂粒子を、採水運転に供する前に、予め、該樹脂粒子に物理的及び／又は化学的な破砕作用を与えて、内部歪みや微細亀裂らの潜在的欠陥を持っている樹脂粒子のみを破砕させる第１プロセスと、第１プロセスで破砕された樹脂粒子を健全樹脂粒子から除去する第２プロセスにより潜在的欠陥を持っている樹脂粒子を含まないものとした、健全樹脂粒子を脱塩装置に充填し、採水運転を行うことにより、経時的使用における微細樹脂粒子や破砕樹脂粒子の発生を無くし、水質向上を図る方法を発明するに至った。
【０００６】
前述の第１プロセスは、脱塩装置に使用する陽イオン交換樹脂粒子及び／又は陰イオン交換樹脂粒子を、採水運転に供する前に、予め、水を張った容器に収容し、ポンプによる循環運転、撹拌機等による撹拌、又は超音波の発信を断続的又は連続的に３０分以上実施する物理的破砕手段、乾燥機などによりイオン交換樹脂を官能基が分解しない程度に加熱した後、注水する熱応力による破砕手段、或いは、樹脂を再生剤である塩酸、硫酸、硝酸、苛性ソーダ、食塩等の比較的濃度の高い薬品に浸漬した後、純水により十分に洗浄する浸透圧による破砕手段のいずれか、又はその組み合わせにより、内部歪みや微細亀裂等の潜在的欠陥を持っている樹脂粒子を破砕するものである。
【０００７】
また、前述の第２プロセスは、第１プロセスにより破砕処理をした樹脂粒子を空気又は窒素ガスによるスクラビングの後に展開率１００％以上、望ましくは、２００％で３０分以上逆洗し、オーバーフローにより除去する手段、又は、乾燥状態、或いは、水と一緒に樹脂粒子を振動ふるい等に連続的又はバッチにて導入し、破砕した樹脂粒子をふるい落とす手段により、健全樹脂粒子より破砕樹脂粒子を効率的に除去するものである。
【０００８】
本発明は、また、イオン交換樹脂粒子の状態を、予め、サンプリングした樹脂粒子の顕微鏡観察等により確認しておき、最適な破砕樹脂粒子除去手段を前述の第１プロセス及び第２プロセスから選択し、適宜、組み合わせることを特徴とする脱塩装置の経時的使用における微細樹脂粒子や破砕樹脂粒子の発生を無くし、効果的かつ経済的に水質向上を図る方法を提供するものである。
【０００９】
本発明は、さらに、第１プロセスの各手段と、第２プロセスの各手段を、脱塩装置の運転操作の樹脂充填工程に、予め組み込むことにより脱塩装置の運転と連係可能とし、これらを自動運転するためにシーケンサー、又はプログラムタイマー等を使用することにより運転制御することを特徴とする脱塩装置の経時的使用における微細樹脂粒子や破砕樹脂粒子の発生を無くし、水質向上を図る方法を提供するものである。
本発明を具体的に実施する装置は、陽イオン交換樹脂粒子及び／又は陰イオン交換樹脂粒子に物理的及び／又は化学的な破砕作用を与えて、内部歪みや微細亀裂らの潜在的欠陥を持っている樹脂粒子のみを破砕させる第１プロセスと、第１プロセスで破砕された樹脂粒子を健全樹脂粒子から除去する第２プロセスにより、潜在的欠陥を持っている樹脂粒子を含まない健全樹脂粒子を充填したことを特徴とする脱塩装置である。
【００１０】
本発明は、その上、新品イオン交換樹脂粒子のみならず、脱塩装置において経年使用した樹脂粒子をサンプリングし、押漬し強度試験を実施した結果、物理的強度の低下が確認された（シャチロン計などによる再生済み樹脂粒子６０粒の平均荷重強度３５０g／粒以下、２００g／粒以下の割合５％以上）イオン交換樹脂粒子に適用し、潜在的欠陥のない健全樹脂粒子のみを確保し、脱塩装置に充填し採水運転を行うことにより、延命化使用における微細樹脂粒子や破砕樹脂粒子の発生を無くし、水質向上を図る方法を提供するものである。
本発明で処理するイオン交換樹脂は、粒状のものであり、樹脂粒子として取り扱われるものであり、その樹脂粒子の粒径としては、通常０．３５〜１．２ｍｍの範囲のものである。
【００１１】
【実施例】
以下、実施例により本発明を更に詳細に説明するが、本発明は下記実施例に限定されるものではない。
【００１２】
実施例１
１．サンプルの準備
市販されている複数の強酸性ゲル型陽イオン交換樹脂粒子を純水中に浸漬し、それを十分に混合し、その中より１〜２ｍｌをサンプリングして、光学顕微鏡により約２０００粒〜４０００粒を観察し真球率を測定する。真球率は、観察したイオン交換樹脂粒子の総数に対する健全球（無亀裂及び無破砕球）の割合として表示する。また、亀裂球の認識は粒子に対する下方からの透過光、上方からの反射光、及び粒子に対する傾斜光を組み合わせて行い、通常では認識されないような微小亀裂についても検出し亀裂球としてカウントした。その結果、以下の第１表に示す通り、真球率が求められた。
【００１３】
【表１】

【００１４】
２．第１プロセス（亀裂粒子の破砕プロセス）
上記の第１表の通り準備したサンプルＡ、Ｂ、Ｃについて、次の通り亀裂球の破砕試験を実施した。
【００１５】
ａ．ポンプ循環法
・試験方法
マグネチックポンプ１の出口、入口に長さ約３０ｃｍ、内径９ｍｍのシリコーンゴム製チューブ２を嵌め、その両端を５００ｍｌのプラスチックビーカ３に入れ、下記の如く樹脂スラリーが循環し易い様に固定した。
このビーカ３内に樹脂粒子を水と共に移し、スラリーの循環運転を行い、樹脂粒子同士及びポンプインペラによる磨耗により亀裂球（粒子）を破砕した。循環運転中に樹脂を適宜サンプリングし、亀裂球、破砕樹脂粒子の割合を測定した。
試験条件を第２表に示す。
【００１６】
【表２】

【００１７】
・試験結果
サンプルＡ、Ｂ、Ｃに対してポンプ循環運転を３０分実施し、１０分毎に樹脂をサンプリングし、亀裂球、破砕球及び健全球の割合を測定した結果を以下の第３表〜第５表に示す。
【００１８】
【表３】

【００１９】
【表４】

【００２０】
【表５】

【００２１】
いずれのケースも、亀裂球は０．２％以下に大幅に低減され、その代わりとして、破砕球が増加している。増加した破砕球は、次の第２プロセスの逆洗オーバーフロー又は振動ふるいにより除去し、健全球のみを確保することが出来た。
また、亀裂球の破砕法は上述のポンプ循環法のほかに、樹脂を再生剤｛硫酸、塩酸、苛性ソーダなど｝に浸漬する浸透圧ショック法、樹脂を加温後、注水する熱応力ショック法、並びに、これら方法の組み合わせが考えられる。更なる実施例として、浸透圧ショック法＋ポンプ循環法について記載する。
【００２２】
ｂ．浸透圧ショック法＋ポンプ循環法
・試験方法
前述のサンプルの準備と同様の方法で、市販されている強酸性ゲル型陽イオン交換樹脂粒子を純水中に浸漬し、真球率を測定した。これをサンプルＤとする。
測定結果を第６表に示す。
【００２３】
【表６】

【００２４】
準備したサンプルＤは、亀裂球の割合が比較的多く（従来の検査では検出できないような潜在的亀裂についても確認した）、ポンプ循環法だけでは亀裂球の破砕が十分でないことが予想されるため、浸透圧ショック法との組み合わせ法を適用した。
【００２５】
先ず、上記サンプルＤの４０ｍｌを十分水切りした後、約３０ｗｔ％程度の硫酸の入ったビーカに入れ、３０分間撹拌する。次に５分程度、沈静させた後、硫酸を排出する。更に樹脂の２５倍量の純水をビーカに一挙に注ぎ、そのまま３０分間撹拌した後、樹脂粒子を液から分離し水洗し、樹脂粒子の真球率を測定した。
次に、この樹脂粒子を上述のポンプ循環法により、スラリーの循環運転を行い、樹脂同士及びポンプインペラによる磨耗により亀裂球を破砕した。循環運転中に樹脂を適宜サンプリングし、亀裂球、破砕樹脂の割合を測定した。
試験条件を第７表に示す。
【００２６】
【表７】

【００２７】
ポンプ循環法の試験条件は、前述したａ項のポンプ循環法の通りである。
・試験結果
サンプルＤに対して浸透圧ショック法＋ポンプ循環法を実施し、各工程毎に樹脂粒子をサンプリングし、亀裂球、破砕球及び健全球の割合を測定した結果を以下の第８表及び第９表に示す。
【００２８】
【表８】

【００２９】
【表９】

【００３０】
サンプルＤの亀裂球は、７．０％から０．１％に大幅に低減され、その代わりとして、前述と同様に破砕球が増加していた。増加した破砕球は、次の第２プロセスの逆洗オーバーフロー又は振動ふるいにより除去し、健全球のみを確保することが出来た。
【００３１】
３．第２プロセス
亀裂球の破砕試験を実施した前述のサンプルＡ、Ｂ、Ｃ、Ｄについて、破砕球の分離試験を実施した。
【００３２】
ｃ．逆洗分離法
・試験方法
破砕球を含むサンプルＡ〜Ｃの樹脂粒子５を各々４０ｍｌを、図２に示すように逆洗用の分離カラム６に充填し、カラム６下部より純水槽８からの純水７を逆洗水ポンプ９により注入し樹脂粒子５を上部に十分に展開させ、沈静させた後、サイフォン１１によりカラム６上方に集まった破砕樹脂粒子を除去した。
破砕樹脂粒子の除去は、複数回、逆洗展開を行い、その都度、少量ずつ実施した。破砕樹脂粒子の抜き出し総量は、予め、測定した真球率のデータに基づき決定した。図２中、１０は流量計、１２は廃樹脂粒子受けである。
試験条件を第１０表に示す。
【００３３】
【表１０】

【００３４】
・試験結果
上記試験条件により逆洗分離を実施した結果を以下の第１１表にまとめる。
【００３５】
【表１１】

【００３６】
上記の第１１表に示す結果の通り、真球率は何れも９９％以上と極めて良好であった。なお、樹脂の回収量を現状より若干低減することにより更なる真球率のアップも可能となるが、従来の真球率の測定法では、いずれも１００％であることより、現状の到達レベルは、汎用樹脂のレベルをはるかに越える高レベルであると言っても差し支えない。更なる破砕球の分離法として、長方形目開きスクリーンによる水ふるい法について記載する。
【００３７】
ｄ．長方形目開きスクリーンによる水ふるい法
・試験方法
破砕球を含むサンプルＤの樹脂４０ｍｌを、長方形の目開きスクリーンに純水と一緒に入れて、上方より純水を加えつつ、スクリーンを上下左右に揺すりながら、破砕樹脂粒子をスクリーン下方の破砕樹脂粒子受けに排出する。スクリーン上部の樹脂粒子を回収し真球率を測定した。
試験条件を第１２表に示す。
【００３８】
【表１２】

【００３９】
・試験結果
上記試験条件によりふるいを実施した結果を以下の第１３表にまとめる。
【００４０】
【表１３】

【００４１】
上記第１３表に示す結果の通り、真球率は９９％以上と極めて良好である。また、樹脂粒子の回収率は逆洗分離法に比べて良好である。従来の真球率の測定法では、いずれも１００％であることより、現状の到達レベルは、汎用樹脂粒子のレベルをはるかに越える高レベルであると言っても差し支えない。
【００４２】
４．樹脂健全性の確認
第１プロセス及び第２プロセスにより製造した健全樹脂のサンプルＡ及びＤを使用し、樹脂の健全性を以下の通り評価した。
【００４３】
・評価試験方法
第１プロセスで破砕試験に使用したポンプ循環法により確保した健全樹脂粒子のサンプルＡ及びＤの、図１に示す樹脂スラリー循環装置での循環運転を行い、その後、真球率を測定した。
容量５００ｍｌのビーカ１内に樹脂粒子２を水と共に移し、マグネティクポンプ３とシリコーンゴム製チューブ４とにより形成される循環回路を通してスラリーの循環運転を行い、循環運転終了後に樹脂粒子をサンプリングし、亀裂球、破砕樹脂の割合を測定する。
試験条件を第１４表に示す。
【００４４】
【表１４】

【００４５】
・試験結果
サンプルＡ、Ｄに対してポンプ循環運転を６０分実施し、運転終了後に樹脂粒子をサンプリングし、亀裂球、破砕球及び健全球の割合を測定した結果を以下の第１５表に示す。
【００４６】
【表１５】

【００４７】
試験の結果、真球率は９９％以上と極めて良好であり、前述の第１及び第２プロセスにおいて精製された健全球は、ポンプ循環による耐磨耗性試験においても、新たに破砕されないことが確認された。
なお、破砕球の割合が微増しているが、これらは元から存在している破砕球及び亀裂球の一部が再度破砕したことによると推測される。
【００４８】
【発明の効果】
以上、詳細に説明したように本発明によれば、下記のような優れた効果が期待される。
（１）従来、ＢＷＲ復水脱塩装置で使用されているイオン交換樹脂粒子は、本発明のような亀裂球及び破砕球の破砕処理及び除去処理を実施しておらず、樹脂粒子をプラントに充填する際に樹脂粒子に加わる荷重により、一部の亀裂樹脂粒子の破砕が発生すること、並びに製造時に発生した破砕粒子が残留していることにより、これら破砕樹脂粒子及びその破砕部分が運転中に復水脱塩装置よりスクリーンを通過し下流に流出し、原子炉に入り分解し水質の悪化を招く可能性がある。
本発明により処理して亀裂樹脂粒子及び破砕樹脂粒子を除去したイオン交換樹脂粒子をＢＷＲプラントに使用したところ、原子炉水の導電率は、イオン交換樹脂交換前の値、０．１μＳ／ｃｍに対して、０．０７μＳ／ｃｍ以下に低下し、良好に推移している。また、炉水の硫酸イオン濃度も、イオン交換樹脂交換前の値、４ｐｐｂに対して１ｐｐｂ以下に低下し良好に推移している。このように本発明を適用することにより、脱塩装置の処理水質の飛躍的な向上が達成できる。
【００４９】
（２）本発明を定期的に脱塩装置用のイオン交換樹脂粒子に適用することにより、効率的に亀裂球及び破砕球の除去が可能となり、運転時における処理水の高純度維持が可能となる。
（３）長期間に渡り、脱塩装置に使用したイオン交換樹脂に対して、本発明を適用することにより、効率的に樹脂粒子中に存在する亀裂球及び破砕球を除去することが出来、健全球のみを確保することができる。この樹脂粒子を脱塩装置に充填することにより、良好な水質を維持することが可能となる。
【図面の簡単な説明】
【図１】第１プロセスのポンプ循環法を行う樹脂スラリー循環装置の概略説明図である。
【図２】逆洗分離法による破砕樹脂粒子の分離装置の概略説明図である。
【符号の説明】
１５００ｍｌビーカー
２樹脂粒子
３マグネチックポンプ
４シリコーンゴム製チューブ
５イオン交換樹脂
６逆洗分離カラム
７純水
８純水タンク
９逆洗水ポンプ
１０流量計
１１サイフォン
１２廃樹脂粒子受け[0001]
BACKGROUND OF THE INVENTION
The present invention efficiently removes resin particles having potential defects present in resin particles for ion exchange resins used in a desalination apparatus, maintains the resin particles physically healthy, The present invention relates to a water passing method of a desalinator for eliminating leakage of fine resin particles and crushed resin particles (including particle pieces) and improving the quality of treated water.
[0002]
[Prior art]
When the ion exchange resin particles are filled in the desalination unit and the water flow operation is performed, first, the cation exchange resin particles and / or anion exchange resin particles to be filled are filled together with water in the desalting tower or the regeneration tower. To do. Then, water is filled up to a level exceeding the level of the ion exchange resin particles contained in the tower, air is injected from the bottom of the tower, the ion exchange resin particles are stirred, and the fine resin particles and crushed resin present in the resin particle mixture Free the particles into water. Next, backwash water is injected from the bottom of the tower to sufficiently develop the resin layer, and the fine resin particles and crushed resin particles that have come out on the top of the resin layer are overflowed and discharged out of the system. This operation is repeated a plurality of times to remove fine resin particles and crushed resin particles in the resin layer. After the resin particles are mixed and transferred to the desalting tower, the water passing operation of the desalting tower is started. In the case where resin particles are directly packed in the desalting tower, all the above operations are performed in the desalting tower and the water flow operation is started.
[0003]
[Problems to be solved by the invention]
In the method of filling the ion exchange resin into the desalinator mentioned above and using it for water flow operation, the ion exchange resin particles having potential defects such as internal distortion and fine cracks mixed in sound ion exchange resin particles are completely removed. Cannot be removed. Therefore, if backwashing regeneration, drug regeneration, resin transfer accompanying this, continuous water sampling operation, etc. are continued, ion-exchange resin particles having potential defects may be crushed in the process. high. These crushed resin particles are difficult to remove sufficiently by normal backwash regeneration, and leak to the downstream side due to the differential pressure applied to the resin layer during water flow operation and transient impacts when the desalting tower is introduced. There is a possibility of causing deterioration of treated water.
[0004]
The present invention has been made in view of such circumstances, and for ion exchange resin particles used in a desalting apparatus, resin particles having potential defects present in the resin particles are efficiently removed, The present invention provides a method for improving the water quality of a desalinating apparatus for maintaining the resin particles physically sound, eliminating the leakage of fine resin particles and crushed resin particles into the treated water, and improving the quality of the treated water.
[0005]
[Means for Solving the Problems]
As a result of various investigations to achieve the above-mentioned object, the present inventors, before using the cation exchange resin particles and / or anion exchange resin particles used in the desalting apparatus for the water sampling operation, The resin particles were physically and / or chemically crushed so as to crush only the resin particles having potential defects such as internal strain and microcracks, and crushed in the first process. By removing the resin particles from the sound resin particles by the second process, the resin particles that do not contain the potential defects are filled in the desalinator and the water sampling operation is performed over time. The inventors have invented a method for improving the water quality by eliminating generation of fine resin particles and crushed resin particles during use.
[0006]
In the first process described above, the cation exchange resin particles and / or anion exchange resin particles used in the desalination apparatus are stored in a container filled with water in advance before being subjected to a water sampling operation, and are circulated by a pump. Water is injected after heating the ion-exchange resin to the extent that the functional groups are not decomposed by a physical crushing means that performs operation, stirring by a stirrer, etc., or by intermittently or continuously performing transmission of ultrasonic waves for 30 minutes or more, a dryer, etc. Crushing means by thermal stress or by osmotic pressure washing thoroughly with pure water after immersing the resin in a relatively high concentration chemical such as hydrochloric acid, sulfuric acid, nitric acid, caustic soda, salt, etc. Either or a combination thereof crushes resin particles having potential defects such as internal strain and microcracks.
[0007]
In the second process described above, the resin particles crushed by the first process are scrubbed with air or nitrogen gas and then back-washed at a development rate of 100% or more, preferably 200% for 30 minutes or more, and removed by overflow. The crushed resin particles are more efficient than the sound resin particles by means of removing the crushed resin particles in a dry state or by introducing the resin particles into a vibrating screen continuously or batchwise with water. To be removed.
[0008]
In the present invention, the state of the ion exchange resin particles is confirmed in advance by microscopic observation of the sampled resin particles, and the optimum crushed resin particle removing means is selected from the first process and the second process. The present invention provides a method for effectively and economically improving water quality by eliminating generation of fine resin particles and crushed resin particles over time of a desalting apparatus, which is suitably combined.
[0009]
The present invention further enables each means of the first process and each means of the second process to be linked to the operation of the desalting apparatus by incorporating them in the resin filling step of the operation of the desalting apparatus. A method for improving the water quality by eliminating the generation of fine resin particles and crushed resin particles over time of a desalinator, which is controlled by using a sequencer or a program timer for automatic operation. It is to provide.
An apparatus that specifically implements the present invention applies a physical and / or chemical crushing action to cation exchange resin particles and / or anion exchange resin particles to eliminate potential defects such as internal strains and microcracks. Healthy resin particles that do not contain resin particles that have potential defects by the first process that crushes only the resin particles that have them and the second process that removes the resin particles crushed in the first process from the healthy resin particles Is a desalinization device filled with
[0010]
In addition, the present invention sampled not only new ion exchange resin particles but also resin particles used over time in a desalination apparatus, and conducted a strength test by squeezing them. As a result, a decrease in physical strength was confirmed (Chatsilon The average load strength of 60 regenerated resin particles by a meter etc. 350g / grain or less, 200g / grain ratio 5% or more) Apply to ion-exchange resin particles, ensure only healthy resin particles without potential defects, It is intended to provide a method for improving the water quality by filling a salt device and performing a water sampling operation to eliminate generation of fine resin particles and crushed resin particles in life extension use.
The ion exchange resin processed by this invention is a granular thing, and is handled as a resin particle, As a particle size of the resin particle, it is a thing of the range of 0.35-1.2 mm normally.
[0011]
【Example】
EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to the following Example.
[0012]
Example 1
1. Sample preparation A plurality of commercially available strongly acidic gel-type cation exchange resin particles were immersed in pure water, mixed well, and 1 to 2 ml of the sample was sampled, and about 2000 particles were observed with an optical microscope. ˜4000 grains are observed and the sphericity is measured. The true sphere ratio is displayed as a ratio of healthy spheres (non-cracked and non-crushed spheres) to the total number of ion-exchange resin particles observed. The crack sphere was recognized by combining transmitted light from below with respect to the particles, reflected light from above, and tilted light with respect to the particles, and even microcracks that were not normally recognized were detected and counted as crack spheres. As a result, as shown in Table 1 below, the true sphere ratio was determined.
[0013]
[Table 1]

[0014]
2. First process (crack particle crushing process)
About the sample A, B, and C prepared as said Table 1, the crushing test of the crack sphere was implemented as follows.
[0015]
a. Pump circulation method and test method Fit a silicone rubber tube 2 with a length of about 30 cm and an inner diameter of 9 mm at the outlet and inlet of the magnetic pump 1, put both ends into a 500 ml plastic beaker 3, and circulate the resin slurry as shown below. Fixed to be easy.
Resin particles were transferred into the beaker 3 together with water, and the slurry was circulated. The cracked spheres (particles) were crushed by abrasion with the resin particles and the pump impeller. The resin was sampled appropriately during the circulation operation, and the ratio of cracked spheres and crushed resin particles was measured.
The test conditions are shown in Table 2.
[0016]
[Table 2]

[0017]
-Test results Pump circulation operation was performed for samples A, B, and C for 30 minutes, the resin was sampled every 10 minutes, and the results of measuring the ratio of cracked spheres, crushed spheres, and healthy spheres are shown in Table 3 below. To Table 5.
[0018]
[Table 3]

[0019]
[Table 4]

[0020]
[Table 5]

[0021]
In either case, cracked spheres are greatly reduced to 0.2% or less, and instead, crushed spheres are increased. The increased crushed spheres were removed by backwash overflow or vibration sieve in the next second process, and only healthy spheres could be secured.
In addition to the above-described pump circulation method, cracked ball crushing methods include an osmotic shock method in which a resin is immersed in a regenerant {sulfuric acid, hydrochloric acid, caustic soda, etc.}, a thermal stress shock method in which water is poured after heating the resin, A combination of these methods is also conceivable. As a further example, an osmotic shock method and a pump circulation method will be described.
[0022]
b. Osmotic Shock Method + Pump Circulation Method / Test Method In the same manner as the sample preparation described above, commercially available strongly acidic gel cation exchange resin particles were immersed in pure water, and the sphericity was measured. This is designated as sample D.
The measurement results are shown in Table 6.
[0023]
[Table 6]

[0024]
The prepared sample D has a relatively high proportion of cracked spheres (confirmed for potential cracks that could not be detected by conventional inspection), and it is expected that cracking of the cracked spheres will not be sufficient by the pump circulation method alone. A combination method with the osmotic shock method was applied.
[0025]
First, after sufficiently draining 40 ml of the sample D, it is placed in a beaker containing about 30 wt% sulfuric acid and stirred for 30 minutes. Next, after allowing to settle for about 5 minutes, the sulfuric acid is discharged. Further, pure water 25 times the amount of the resin was poured into a beaker at once and stirred as it was for 30 minutes, and then the resin particles were separated from the liquid and washed with water, and the sphericity of the resin particles was measured.
Next, the resin particles were subjected to a slurry circulation operation by the above-described pump circulation method, and the cracked spheres were crushed by abrasion between the resins and the pump impeller. During the circulation operation, the resin was appropriately sampled, and the ratio of cracked spheres and crushed resin was measured.
The test conditions are shown in Table 7.
[0026]
[Table 7]

[0027]
The test conditions of the pump circulation method are the same as the pump circulation method of item a described above.
-Test results The osmotic shock method + pump circulation method was performed on sample D, resin particles were sampled at each step, and the ratio of cracked spheres, crushed spheres, and healthy spheres was measured. And in Table 9.
[0028]
[Table 8]

[0029]
[Table 9]

[0030]
The crack sphere of sample D was greatly reduced from 7.0% to 0.1%, and instead, the number of crushed spheres increased as before. The increased crushed spheres were removed by backwash overflow or vibration sieve in the next second process, and only healthy spheres could be secured.
[0031]
3. For the above-mentioned samples A, B, C, and D that were subjected to the crushing test for the second process cracked sphere, a crushing sphere separation test was performed.
[0032]
c. Backwash Separation Method / Test Method 40 ml each of resin particles 5 of Samples A to C containing crushed spheres are filled into a separation column 6 for backwashing as shown in FIG. Pure water 7 was injected by a backwash water pump 9 and the resin particles 5 were sufficiently developed on the top and allowed to settle, and then the crushed resin particles collected above the column 6 were removed by the siphon 11.
Removal of the crushed resin particles was performed by backwashing a plurality of times, and each time, small amounts were carried out. The total amount of the crushed resin particles extracted was determined in advance based on measured sphericity data. In FIG. 2, 10 is a flow meter, and 12 is a waste resin particle receiver.
The test conditions are shown in Table 10.
[0033]
[Table 10]

[0034]
Test results The results of backwash separation under the above test conditions are summarized in Table 11 below.
[0035]
[Table 11]

[0036]
As the results shown in Table 11 above, the true sphere ratio was extremely good at 99% or more. In addition, it is possible to further increase the sphericity by slightly reducing the amount of resin recovered from the current level. However, all the conventional methods for measuring the sphericity are 100%. Can be said to be a high level far exceeding that of general-purpose resins. A water sieving method using a rectangular aperture screen will be described as a further method of separating crushed spheres.
[0037]
d. Water sieving method and test method using a rectangular mesh screen 40 ml of sample D resin containing crushed spheres is placed in a rectangular mesh screen together with pure water, and the screen is shaken up, down, left and right while adding pure water from above. The crushed resin particles are discharged to the crushed resin particle receiver below the screen. The resin particles at the top of the screen were collected and the sphericity was measured.
Table 12 shows the test conditions.
[0038]
[Table 12]

[0039]
Test results The results of sieving under the above test conditions are summarized in Table 13 below.
[0040]
[Table 13]

[0041]
As the results shown in Table 13 above, the true sphere ratio is extremely good at 99% or more. Further, the recovery rate of the resin particles is better than that of the backwash separation method. Since all the conventional methods for measuring the sphericity are 100%, it can be said that the current level reached is a high level far exceeding the level of general-purpose resin particles.
[0042]
4). Confirmation of Resin Soundness Using sound resin samples A and D produced by the first process and the second process, the soundness of the resin was evaluated as follows.
[0043]
・ Evaluation test method Samples A and D of sound resin particles secured by the pump circulation method used in the crushing test in the first process are circulated in the resin slurry circulator shown in FIG. It was measured.
The resin particles 2 are transferred together with water into the beaker 1 having a capacity of 500 ml, and the slurry is circulated through a circulation circuit formed by the magnetic pump 3 and the silicone rubber tube 4, and the resin particles are sampled after the circulation operation is completed. Measure the ratio of cracked spheres and crushed resin.
Table 14 shows the test conditions.
[0044]
[Table 14]

[0045]
-Test results The pump circulation operation was performed for samples A and D for 60 minutes, the resin particles were sampled after the operation was completed, and the ratios of cracked spheres, crushed spheres and healthy spheres were measured and the results are shown in Table 15 below. .
[0046]
[Table 15]

[0047]
As a result of the test, the sphericity rate is extremely good at 99% or more, and the healthy sphere refined in the first and second processes described above may not be newly crushed even in the abrasion resistance test by the pump circulation. confirmed.
In addition, although the ratio of the crushing sphere has increased slightly, it is estimated that these are caused by crushing a part of the crushing sphere and the cracked sphere that are originally present.
[0048]
【The invention's effect】
As described above in detail, according to the present invention, the following excellent effects are expected.
(1) Conventionally, the ion-exchange resin particles used in the BWR condensate demineralizer are not subjected to the crushing and removing treatment of cracked spheres and crushing spheres as in the present invention, and the resin particles are used in the plant. Due to the load applied to the resin particles during filling, some of the cracked resin particles are crushed, and the crushed particles generated during production remain, so that these crushed resin particles and their crushed parts are in operation. However, it may pass through the screen from the condensate demineralizer and flow out downstream, which may enter the reactor and decompose to cause deterioration of water quality.
When ion exchange resin particles treated with the present invention to remove cracked resin particles and crushed resin particles were used in a BWR plant, the reactor water conductivity was 0.1 μS / cm, the value before ion exchange resin exchange. On the other hand, it has decreased to 0.07 μS / cm or less, and is in a favorable state. In addition, the sulfuric acid ion concentration in the reactor water also shows a favorable transition, decreasing to 1 ppb or less compared to 4 ppb before the ion exchange resin exchange. By applying the present invention in this way, a dramatic improvement in the quality of treated water in the desalinator can be achieved.
[0049]
(2) By periodically applying the present invention to ion-exchange resin particles for a desalination apparatus, it becomes possible to efficiently remove cracked spheres and crushed spheres, and maintain high purity of treated water during operation. Become.
(3) By applying the present invention to the ion exchange resin used in the desalting apparatus over a long period of time, it is possible to efficiently remove the cracked spheres and crushed spheres present in the resin particles, Only healthy spheres can be secured. By filling the resin particles in a desalting apparatus, it is possible to maintain good water quality.
[Brief description of the drawings]
FIG. 1 is a schematic explanatory diagram of a resin slurry circulating apparatus that performs a pump circulation method of a first process.
FIG. 2 is a schematic explanatory diagram of an apparatus for separating crushed resin particles by a backwash separation method.
[Explanation of symbols]
1 500 ml beaker 2 resin particles 3 magnetic pump 4 silicone rubber tube 5 ion exchange resin 6 backwash separation column 7 pure water 8 pure water tank 9 backwash water pump 10 flow meter 11 siphon 12 waste resin particle receiver

Claims

Before the cation exchange resin particles and / or anion exchange resin particles used in the desalting apparatus are subjected to a water sampling operation, the resin particles are subjected to a physical and / or chemical crushing action in advance. The first process that crushes only resin particles that have potential defects such as strain and microcracking, and the second process that removes resin particles crushed in the first process from healthy resin particles have potential defects. A method for improving the water quality of a desalinator, characterized in that the desalinator is filled with healthy resin particles that do not contain the resin particles that are present, and a water sampling operation is performed.

In the first process, the ion exchange resin particles to be used are accommodated in a container filled with water, and a means for intermittently or continuously performing circulation operation by a pump, stirring by a stirrer or the like, or transmission of ultrasonic waves, After the ion-exchange resin is heated to such an extent that the functional groups are not decomposed by a drier, etc., or after the resin is immersed in a relatively high concentration chemical such as hydrochloric acid, sulfuric acid, nitric acid, caustic soda, sodium chloride, etc. , One of the means for sufficiently washing with pure water, or a combination thereof, the second process is to backwash the crushed resin after scrubbing with air or nitrogen gas at a development rate of 100% or more for 30 minutes or more. 2. The means for removing, or a means for sieving the resin crushed together with water in a dry state or with a vibrating screen or the like. Water quality improvement method of salt apparatus.

Each means of the first process can be linked to the operation of the desalting apparatus by incorporating it in the operation of the desalting apparatus in advance, and is automatically operated by using a sequencer, a program timer or the like. The method for improving the water quality of a desalinating apparatus according to claim 1.

Apply to not only new ion exchange resin particles but also ion exchange resin particles that have been used for a long time in a desalinator and have reduced physical strength, ensuring only healthy resin particles without potential defects, and filling the desalter. 2. The method for improving the water quality of a desalinating apparatus according to claim 1, wherein the water quality is improved by eliminating the generation of fine resin and crushing resin in life extension use by performing a water sampling operation.

First, a physical and / or chemical crushing action is applied to the cation exchange resin particles and / or anion exchange resin particles to crush only the resin particles having potential defects such as internal strain and fine cracks. Desalination apparatus filled with healthy resin particles not containing resin particles having a potential defect by a process and a second process of removing resin particles crushed in the first process from the healthy resin particles .