GB191224057A - A Process of, and Apparatus for, Separating Fibrous Matter from Admixed Particles and Adhering Matter. - Google Patents

Abstract

24,057. Werst, J. J., CollÚe, P. M. H. L., and Egmond, J. M. Oct. 21. Pulp, preparation of.-In separating fibrous material such as waste paper, rags, sawdust, &c. from admixed particles and adhering matter, two immiscible or nearly immiscible liquids of different specific weights are used, the two liquids having different affinities, the one for the fibrous matter and the other for the foreign matter. Preliminary treatment may be necessary to render the mixture amenable to the separation. In separating. printers' ink, size, &c. from waste paper, so that the cellulose can be used again, the waste paper is first boiled under pressure in a solution of a sulphite such as sulphite of soda. The woody matter is thus converted into cellulose, and bleaching is effected. The mass is then washed, until neutral, with water or weakly acid liquor, diluted to a thin pulp, and passed to an emulsifying-appliance A, where it is mixed with a suitable oil such as benzine by the action of rotary plates b disposed between stationary plates or funnels c, or between plates or funnels rotating in the opposite direction. The mixture flows to a separator B, where the benzine or oil, under the action of slowly revolving arms f and long thin pins v mounted on the same or on different shafts, rises to the top and carries with it the foreign matter, while the pulp and water fall to the bottom. The benzine or oil is drawn off into a vessel g, where it is sprayed with water to separate any fibrous matter carried over, and it is then run into a vessel l through a finemesh sieve r, which keeps back any fibrous matter still present, and the foreign matter is removed by means of a filter m preferably of charcoal. A vessel n serves for the separation of the benzine from any remaining water, the benzine flowing off through a pipe p and the water through a tap o. Pulp from the separator B may be further treated in other emulsifying-appliances A<1>, A<2> and separators B<1>, B<2>, the benzine or oil being introduced through pipes N. Where the paper is printed with ink containing metallic salts, soluble sulphides, thiosulphates, or thionates may be used for the preliminary treatment.