Process and plant for recycling waste printed papers
US4865690A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Mar 8, 1988 |
| Grant date | Sep 12, 1989 |
| Priority date | — |
| Expiry date | Mar 8, 2008 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02W30/64
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
Process for improving the quality of deinked papermaking pulps obtained by ecycling waste printed papers, in which: PA0 the papers are converted into a slush pulp (1), PA0 most of the ink (12) is removed (11) from this slush pulp, especially by selective primary flotation of the ink, and PA0 the deinked pulp is washed (5) to remove the residual ink before being conveyed into the circuit (14) for utilization of the pulp, wherein the waters (24) from this washing (5) are first of all subjected to a selective secondary flotation (16) to remove (17) only the residual ink therefrom, the suspension of the remaining matter (fibers and fillers) (18-23) being subsequently mixed with the pulp (15) originating from the washing (5). The invention also relates to a plant for making use of this process.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.