従って、本発明の目的は、濃縮水へ薬剤を添加することなく、電気式脱イオン水製造装置の構造面からの抜本的な改善により電気抵抗を低減すると共に、濃縮室内でのスケール発生を抑制することができ、且つ被処理水からのイオン除去能を向上させることにより高度の水質を長期間に渡り安定して得ることができる脱イオン水の製造方法を提供することにある。
Accordingly, an object of the present invention, without the addition of agents to the concentrated water, the drastic improvement of the structured surface of the electrodeionization water producing apparatus while reducing the electrical resistance, the scale onset production in concentrate chamber It is an object of the present invention to provide a method for producing deionized water that can be suppressed and improve the ability to remove ions from the water to be treated, whereby a high level of water quality can be stably obtained over a long period of time.
第１小脱塩室又は第２小脱塩室の厚さは特に制限されず、第１小脱塩室又は第２小脱塩室に充填されるイオン交換体の種類と充填方法によって、最適な厚さを決定すればよい。従って、第１小脱塩室の厚さを３mm、第２小脱塩室の厚さを６mmとして、全体の厚さ、すなわち脱塩室の厚さを９mmとしてもよい。このように、複数の脱塩室と濃縮室を交互に配置し、脱塩室の両側に配されるカチオン交換膜とアニオン交換膜で区画される脱塩室の厚みは、従来のものよりも厚くでき、１．５〜１８mmの範囲、好適には、６．５〜１５mm、更に好適には９〜１３mmの範囲で適宜決定される。
The thickness of the first small desalination chamber or the second small desalination chamber is not particularly limited, and is optimal depending on the type of the ion exchanger packed in the first small desalination chamber or the second small desalination chamber and the filling method. What is necessary is just to determine the appropriate thickness. Therefore, the thickness of the first small desalination chamber may be set to 3 mm and the thickness of the second small desalination chamber may be set to 6 mm, and the overall thickness, that is, the thickness of the desalination chamber may be set to 9 mm. Thus, a plurality of desalination chambers and concentration chambers are alternately arranged, and the thickness of the desalination chamber divided by the cation exchange membrane and the anion exchange membrane arranged on both sides of the desalination chamber is larger than that of the conventional one. can thick, the range of 1.5～18Mm, preferably, 6.5～15Mm, is appropriately determined in a range of 9~13mm and more preferably.
また、脱塩室に充填されるイオン交換体としては、特に制限されず、アニオン交換体単床、カチオン交換体単床及びアニオン交換体とカチオン交換体の混床又はこれらの組合せのものが挙げられる。シリカを多く含有する被処理水を処理する場合、先ず、被処理水を中間イオン交換膜と他側のアニオン交換膜で区画されるアニオン交換体が充填された小脱塩室に流入し、次いでこの小脱塩室の流出水を一側のカチオン交換膜と中間イオン交換膜で区画されるカチオン交換体とアニオン交換体の混合体が充填された小脱塩室に流入し、処理すればシリカを十分に除去できる。また、原子力発電所内の蒸気発生器（ＳＧ）ブローダウン水のようにアンモニウム成分を多く含む被処理水を処理する場合、先ず、被処理水を一側のカチオン交換膜と中間イオン交換膜で区画されるカチオン交換体が充填された小脱塩室に流入し、次いでこの小脱塩室の流出水を中間イオン交換膜と他側のアニオン交換膜で区画されるカチオン交換体とアニオン交換体の混合体が充填された小脱塩室に流入し、処理すればアンモニウムを十分に除去できる。また、イオン交換体としては、イオン交換樹脂、イオン交換繊維などイオン交換機能を有する物質であればいずれでもよく、また、それらを組合せたものであってもよい。
The ion exchanger to be filled in the desalting chamber is not particularly limited, and includes a single bed of an anion exchanger, a single bed of a cation exchanger, a mixed bed of an anion exchanger and a cation exchanger, or a combination thereof. Can be When treating the water to be treated containing a large amount of silica, first, the water to be treated flows into a small desalination chamber filled with an anion exchanger partitioned by an intermediate ion exchange membrane and an anion exchange membrane on the other side, and then The effluent from the small desalination chamber flows into a small desalination chamber filled with a mixture of a cation exchanger and an anion exchanger, which is partitioned by a cation exchange membrane and an intermediate ion exchange membrane on one side. Can be sufficiently removed. When treating water to be treated containing a large amount of ammonium, such as blowdown water of a steam generator (SG) in a nuclear power plant, first, the water to be treated is partitioned by a cation exchange membrane and an intermediate ion exchange membrane on one side. Flows into the small desalination chamber filled with the cation exchanger to be filled, and then the effluent of the small desalination chamber is separated by the intermediate ion exchange membrane and the anion exchange membrane on the other side. If the mixture flows into a small desalting chamber filled and treated, ammonium can be sufficiently removed. Further, the ion exchanger may be any substance having an ion exchange function such as an ion exchange resin or an ion exchange fiber, or may be a combination thereof.