System and a method for the steam pre-treatment of chips in association with the production of chemical cellulose pulp
US8052843B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 30, 2006 |
| Grant date | Nov 8, 2011 |
| Priority date | — |
| Expiry date | Sep 18, 2028 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD21C3/00
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
The vessel in which the chips are pre-treated with steam (ST) is provided with a ventilation channel at the top of the vessel for the leading away of weak gases to a weak gas system (NCG). A simple safety system has been installed with the aim of guaranteeing that these weak gases do not reach a level of concentration at which these weak gases become explosive. The safety system has a control unit (CPU) that detects a process parameter that is indicative of the fraction of moisture in the weak gases and opens dilution lines that supply air for the dilution of the weak gases in the ventilation channel. It is appropriate that the dilution take place in stages, where the dilution lines are opened in stages with successively increasing temperature of the weak gases.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.