Digester shell extension
US9328458B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | May 20, 2015 |
| Grant date | May 3, 2016 |
| Priority date | — |
| Expiry date | May 20, 2035 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD21C7/08
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
The invention relates to an improved design of the bottom of a continuous digester reducing the torque load on conventional bottom scrapers with scraper arms arranged at an angle α in relation to the horizontal plane in the range between 5°-30°. A simple digester shell extension VE is installed below the lowermost wash screen WS, ending at a small distance D above the end of the outer end of the scraper arm. The shell extension prevents the descending pulp column from expanding below the wash screen and enables easier shaving action from the scraper, using a dilution and expansion volume established at the outer ends of the scraper arms.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.