Apparatus for delignifying and bleaching cellulose pulp
US4177105A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 11, 1976 |
| Grant date | Dec 4, 1979 |
| Priority date | — |
| Expiry date | Jun 11, 1996 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD21C11/06
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
In an apparatus for treating cellulose pulp with oxygen gas by passing the pulp and oxygen gas through a reaction vessel at elevated temperature and pressure, the improvement whereby the exothermic heat of reaction is controlled and the temperature of the pulp being treated is maintained below the point where the pulp would be degraded, the improvement comprising means for withdrawing oxygen gas from the vessel after the gas has been in contact with the pulp, dividing the withdrawn gas into two portions, cooling one of the portions to remove water vapor therefrom, recombining the gas portions whereby the resulting gas has a lower temperature than the gas withdrawn from the vessel and returning the resulting gas to the vessel for further contact with pulp therein, the amount of gas withdrawn from the vessel and the degree of cooling of the cooled portion of withdrawn gas being regulated to maintain the temperature within the vessel below the point where the pulp is degraded.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.