Title:
PROCESS FOR PRODUCING DEIONIZED WATER BY ELECTRICAL DEIONIZATION TECHNIQUE
Document Type and Number:
WIPO Patent Application WO/1997/046492
Kind Code:
A1
Abstract:
A conventional process for producing deionized water by the electrical deionization technique using an electrical deionization apparatus provided with desalting chambers and concentration chambers arranged alternately is problematic in that the rate of removal of silica from nontreated water is low, though it is advantageous in that it can dispense with the regeneration of ion-exchange resins by using chemicals. In order to solve this problem, the process of the invention comprises supplying nontreated water and nonconcentrated water to, respectively, the desalting chambers and the concentration chambers in such a manner that the nontreated water supplied to the desalting chambers and the nonconcentrated water supplied to the concentration chambers flow countercurrently and that the nontreated water supplied to the desalting chambers passes first an anion-exchanger layer and then other ion-exchanger layers. As a result, the migration of the anions to the concentration chambers is accelerated in the anion-exchanger layer, thus improving the rate of silica removal.
Inventors:
SHINMEI YASUTAKA (JP)
KAKUDA MINORU (JP)
KAKUDA MINORU (JP)
Application Number:
PCT/JP1996/001518
Publication Date:
December 11, 1997
Filing Date:
June 03, 1996
Export Citation:
Assignee:
ORGANO CORP (JP)
SHINMEI YASUTAKA (JP)
KAKUDA MINORU (JP)
SHINMEI YASUTAKA (JP)
KAKUDA MINORU (JP)
International Classes:
B01D61/48; B01J47/08; C02F1/469; C02F1/42; C02F1/46; (IPC1-7): C02F1/469; B01D61/48
Foreign References:
| JPH0471624A | 1992-03-06 | |||
| JPH07265865A | 1995-10-17 | |||
| JPS5247580A | 1977-04-15 | |||
| JPH08150326A | 1996-06-11 |
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