WATER TREATMENT APPARATUS AND WATER TREATMENT METHOD

The present invention provides a water treatment device and a water treatment method able to lower the concentration of boron in treated water. A plurality of electrical deionized water production devices have desalination chambers segmented between an anode and a cathode using an anion exchange film positioned on the anode side and a cation exchange film positioned on the cathode side, the desalination chambers being loaded with ion exchange medium. The respective desalination chambers of the plurality of electrical deionized water production devices communicate in series. Water for treatment is flushed through the serially communicating plurality of desalination chambers and treated water flows out. The anion exchange medium is independently loaded into the farthest upstream part of the first desalination chamber and the farthest downstream part of the last desalination chamber, the first desalination chamber being where water for treatment is initially flushed through, and the final desalination chamber being where treated water flows out. At least the cation exchange medium is loaded into some of the plurality of desalination chambers at a portion positioned between the farthest upstream part of the first desalination chamber and the farthest downstream part of the last desalination chamber.