FOERFARANDE FOER SEPARERING AV PARTIKLAR MED AVVIKANDE TAETHET OCH STOR SPECIFIK YTA UR GENOM UPPLOESNING AV AVFALLSPAPPER ERHAOLLET FIBERMATERIAL

摘要

1463776 Pulping waste paper ESCHER WYSS GmbH 17 Feb 1975 [26 Feb 1974] 6606/75 Heading D2A [Also in Division B2] A stock obtained by pulping waste paper and containing less than 80% water is subject to an intensive mechanical shearing stress before separating foreign particles therefrom. Any aluminium foil or synthetic plastics foil present in the stock is rolled up cr curled as a result of the shearing stress applied thereto and forms compact granules which may be separated from the stock in a hydrocyclone or by screening. The curling may be assisted by heating the stock to a temperature at which the synthetic plastics material becomes plastic. In the embodiment shown, paper pulp from a stock pulper 21 passes to a second stock pulper 25 from which the good stock passes to a screening press 29, a heating screw 30 to which superheated steam is supplied and a dispersing apparatus 32. The latter is provided with a rotor and a stator with intermeshing teeth and subjects the stock to an intensive shearing stress. From the apparatus 32 the stock passes to a container 33 where it is diluted, a screening device 35 and a hydrocyclone 37. In another embodiment (not shown) the second stock pulper 25 is replaced by a hydrocyclone (5) and a deflaker (7).