Abstract: For the purpose of separating coarse particles from a liquid such as water, e.g. in the cellulose industry, laundries etc., a vertical container is used in which a nozzle receives liquid from a pump and sprays the liquid in the form of a conical liquid jet up against the underside of a screening cloth. Above this cloth there is an outlet for the liquid, coarse particles impinging against the cloth and falling back to the bottom of the container. In accordance with the invention the total flow from the pump and jet is led off via the screening cloth and outlet above said cloth, the liquid level in the container being disposed between the nozzle and the screening cloth so that the liquid jet is sprayed through a layer of the liquid in the container before reaching the screening cloth.

Abstract: A fractionating apparatus for separating fine fibers from coarse fibers in water containing a certain amount of air. A spray nozzle is arranged in a vessel and directed towards a screening cloth incorporated as a part of the vessel walls and which, on its discharge side, is arranged for free runoff of the fine particles and the part of the liquid passing through the seal means to its discharge side, while coarse particles and the other part of the liquid is bounced off the inner side of the screening cloth and collected in the vessel to a predetermined liquid level maintained by allowing the liquid to depart through an outlet. A desired pressure difference is maintained across the sieve means. The vessel is closed with the exception of the places where the sieve means are situated and where the outlet is arranged.