Patent · US Expired

Process for producing deionized water by electrodeionization technique

US6248226A · kind A · utility

48Cited by
2References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 23, 1999
Grant dateJun 19, 2001
Priority date
Expiry dateFeb 23, 2019

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC02F2201/46115
  • WIPO fieldChemical engineering
  • WIPO sectorChemistry

Abstract

In producing deionized water by electrodeionization according to the present invention, feed water and concentrating water are flowed into the ion depletion compartments and the concentration compartments, respectively, in such a way that the current direction of feed water being fed into the ion depletion compartments is opposite to the current direction of concentrating water being fed into the concentration compartments. Further, feed water flowed into each ion depletion compartment is first passed through an anion exchange material layer, and subsequently passed through other ion exchange material layer(s). The migration of anions into the concentration compartments is promoted in the portions of such anion exchange material layers through which feed water is first passed. As a result, the silica removal rate is improved.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.