Method and plant for separating soap from black liquor using a pressure screen
US6165316A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 12, 1999 |
| Grant date | Dec 26, 2000 |
| Priority date | — |
| Expiry date | Jan 12, 2019 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD21C11/0007
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
An alkaline cellulose pulp pulping process treats soap and fiber-containing liquids to separate fibers from the liquids prior to further treatment of the liquids (e.g. by evaporation and combustion, or by cooking to produce tall oil). Black liquor containing soap, and/or washer filtrate containing soap, are fed to one or more soap separating tanks, and then the soap fraction from the top of the tanks is fed to a pressure screen where fiber separation takes place (preferably at a temperature of at least 70.degree. C.). Black liquor may be added to the soap fraction to dilute it, and preferably simultaneously raise its temperature. The pressure screen has a screen surface with holes of 0.4 mm diameter or less, or slots with a width of 0.2 mm or less.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.