Method for treatment of a fibrous material-fluid mixture
AssigneeMaschinenfabrik Andritz Aktiengesellschaft
InventorsJohannes Kappel, Franz Petschauer
Life of this patent
Estimating the term…
Abstract
The invention relates to a method and device for the washing of a medium consistency fibrous slurry, especially a chemical pulp slurry in which the slurry is fed at an inclined angle onto a substantially horizontal portion of circulating filter belt, and then distributed over substantially the entire working width of the filter belt. The distributed slurry is then washed with a washing liquid under localized pressure to produce a slurry having a medium consistency range, i.e., about 8 to 15 percent. In order to increase the consistency to 20 to 40 weight percent, preferably about 30 to about 35 weight percent, the washed slurry is passed to a pressing zone.
Claims12
A method for the treatment of a fibrous slurry having an initial medium consistency which comprises
- passing a feed slurry in its entirety onto a first endless filter belt from above, at an inclined angle with said filter belt;
- immediately thereafter passing the deposited slurry on said filter belt through a distribution zone in which said slurry is distributed substantially across the entire working width of said filter belt by applying a locally limited distributing pressure to said slurry, said distributing pressure being limited solely to said distribution zone;
- passing the distributed slurry to a washing zone in which said slurry is contacted with a washing liquid while under a differential pressure for removal of impurities from said fibrous slurry;
- and
- withdrawing the washed slurry from said washing zone, said washed slurry having a reduced impurity content.
Dependencies are inferred from the claim text.