Process for controlling the flow of cellulosic fiber material through an impregnation vessel
US5529661A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 13, 1995 |
| Grant date | Jun 25, 1996 |
| Priority date | — |
| Expiry date | Mar 13, 2015 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD21C3/24
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A process for the continuous digestion of cellulosic fiber material, comprising impregnation with impregnating liquid consisting of at least one fresh digesting liquor, in a closed impregnating system and subsequent digestion with digesting liquid in a closed digester system, said impregnating liquid being supplied through a supply system, together with steamed fibre material, to an inlet end of the impregnating system, liquid being withdrawn from the impregnating system at a point (46) located at a predetermined distance from said inlet end. According to the invention such a first quantity of liquid (F) is withdrawn at said withdrawal point (46) and recirculated directly to the supply system that a predetermined minimum ratio between liquid and fibre material is continuously maintained in the impregnating system prior to said withdrawal point (46), the liquid in said liquid to fibre material ratio being derived from original moisture (A) in the fibre material, condensates (B, C) from an initial steaming of the fibre material, and added fresh digesting liquor(s) (D and/or E) besides said withdrawn and recirculated quantity of liquid (F).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.