Screening apparatus for papermaking pulp
US5307939A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 13, 1992 |
| Grant date | May 3, 1994 |
| Priority date | — |
| Expiry date | Jul 13, 2012 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB01D2201/287
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A hydrodynamic device for generating negative pressure excursions in a pulp slurry during fine screening, includes at least one half-foil member disposed on a substantially cylindrical outer surface of a rotor. The rotor is mounted within and co-axial with a substantially cylindrical screen having a circumferentially continuous apertured zone to define an annular screening chamber between the rotor and the screen. The half-foil member is collectively at least axially co-extensive with the apertured zone and has a leading edge which, also collectively, is inclined at a spiral angle relative to the axis of the rotor such that, in one embodiment, during rotation, the leading edge of the half-foil member conducts large particles downwardly through the screening chamber. A selection of hydrodynamic foil configurations is provided in order to adapt to a wide range of pulp types and screening conditions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.