Patent · US Expired

Method to regenerate gas mixture in ozone-bleaching process

US6059925A · kind A · utility

0Cited by
6References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 8, 1997
Grant dateMay 9, 2000
Priority date
Expiry dateAug 8, 2017

Classification

  • Technology area (CPC D)Textiles; Paper
  • CPC primaryD21C11/0071
  • WIPO fieldTextile and paper machines
  • WIPO sectorMechanical engineering

Abstract

A method of treating cellulose pulp which is subjected to an oxygen-delignification stage (3), a washing stage (4), an ozone-bleaching stage (1) and a further bleaching stage, for instance a peroxide-bleaching stage (7). A gas mixture of oxygen and ozone is delivered to the ozone-bleaching stage (1). The used gas mixture is regenerated, i.e. freed from carbon dioxide, and returned to the oxygen-delignification stage (3) and/or to a bleaching stage (7).

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