Method and apparatus for continuous oxygen bleaching of cellulosic pulp
US4161421A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 13, 1977 |
| Grant date | Jul 17, 1979 |
| Priority date | — |
| Expiry date | Sep 13, 1997 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD21C9/10
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A method and apparatus for continuous oxygen bleaching of cellulosic pulp is provided utilizing first and second pressurized chambers with a number of tubes in fluid communication with both of first and second chambers. Oxygen bearing fluid is intimately mixed with digested cellulosic pulp and is continuously fed under pressure to the first chamber. Communication is selectively provided between the first and second chambers through at least one of the tubular members to allow passage of pulp from the member to the second chamber. The tubular member through which pulp flows to the second chamber is progressively changed as are the members through which passage is blocked, so that the pulp remains within each tubular member sufficient time to allow oxygen-bleaching thereof without degradation, and passes through the members without channelling. The oxygen bleached pulp is continuously discharged from the second chamber. The passage of pulp through the tubular members may either be downwardly or upwardly. The passage between the blocked tubular members and the second chamber is blocked in the first chamber by a rotating plate, the plate having an aperture rotated into communication wi…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.