Method of treatment of waste paper with steam
US5122228A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Dec 10, 1990 |
| Grant date | Jun 16, 1992 |
| Priority date | — |
| Expiry date | Dec 10, 2010 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02W30/64
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
Method is disclosed of treatment of waste paper or the like at high temperatures in the range of 160.degree. C. to about 230.degree. C. The furnish is treated in a digester with or without added chemicals but in the presence of saturated steam. The preferred dwell times are in the range of about 1 minute to about 6 minutes. The treated furnish is then discharged from the digester, preferably, but not exclusively, by an explosive discharge. The advance in the art is in an improved de-inking effect, reduced consumption of chemicals and power. Also, some furnishes previously unsuitable for re-cycling, have been successfully processed by the method of the invention.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.