Method, system and withdrawal screen section for impregnating chips
US8647469B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 25, 2010 |
| Grant date | Feb 11, 2014 |
| Priority date | — |
| Expiry date | Aug 25, 2030 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD21C1/02
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
The method, system and a withdrawal screen section are for the impregnation of chips during the manufacture of chemical pulp. Chips are both steamed and impregnated in a low pressure impregnation vessel, using pressurized hot spent cooking liquor BL as the main part of the impregnation liquid. The hot spent cooking liquor produces most of the steam BLST necessary for steaming the chips. At least two independent first and second screen rows, SC1 and SC1b respectively, are installed in order to improve the process in the impregnation vessel. The first screen row withdraws acidified treatment liquor for disposal which otherwise would be a parasitic acidified waste fluid in the system. The second screen row recirculates treatment fluid back to center of treatment vessel in order to even out the pH profile over the cross section of the vessel.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.