Abstract: An apparatus for filtering liquids comprises a hollow body which is rotatable about a horizontal axis. Liquid to be filtered is supplied into the interior of the rotating hollow body so that filtrate flows by gravity through filter material of the hollow body into a filtrate container. A sealing structure seals between a stationary circumferential wall, which defines a liquid supplying chamber, and a circumferential liquid impervious wall of the hollow body. Wall structures are arranged to prevent unfiltered liquid leaking past the sealing structure from entering the filtrate container.

Abstract: A rotatable filter assembly comprises a rotor in a container for fibre suspension. The center of the rotor is formed by axial discharge tubes into which hollow filter elements, forming annular filter discs open. A collecting hopper extends into the center of the filter assembly. The filter elements keep separately, at least during part of the rotation turn, a lower pressure inside than outside.

Abstract: A rotatable filter assembly, primarily intended for separation of fibers from a fiber suspension, comprises a number of annular filter discs (3) formed by a plurality of filter elements (5). The filter discs are mounted on a horizontal drum rotatable in a container (1) and formed by axial discharge tubes (6) and transverse tubes (7) which communicate with the individual filter elements (5). A collecting hopper (8) extends into the drum through an open end of it. During at least part of the rotation of the drum, the interior of each filter element (5) is kept at a pressure lower than that prevailing at the outside of it. The filter assembly is characterized in that the axial discharge tubes (6), as seen in a cross-sectional view, are arranged in groups each comprising at least two tubes.

Abstract: In a hydrocyclone separator for separating a mixture into one light and one heavy fraction, with a separation chamber consisting partly of one circular cylindrical part and partly of one conical part, the wall of the separation chamber (1, 2) is provided, along a substantial part of its axial elongation, with a means creating a turbulence to a relatively moderate degree and which extends in a screw path (7) opposite to the screw path in which the flow streams along the wall of the separation chamber. Advantageously, at least one guide bar (6) with substantially axial elongation is provided to give the flow, streaming in a screw path along the wall of the separation chamber (1, 2) a radially inwardly directed component. The screw-path-formed limiting surface (7) of said means may form the angle .alpha.=0.degree.-75.degree. to the axial symmetry axis (9) of the separation chamber (1, 2).

Abstract: A strainer device for purification of pulp suspensions comprises a strainer drum with a cylindrical mantle provided with strainer openings. Between the strainer openings are inclined surfaces forming an angle with the flow direction of the suspension, in order that particles contacting the surfaces are given a component of movement radially outwards.

Abstract: A strainer drum for straining pulp and the like comprises a substantially circular cylindrical mantle formed by a number of strainer elements provided with strainer openings, which strainer elements are held together between at least two gables to form the mantle.

Abstract: A separator for separating coarse particles from cellulose pulp suspensions and the like comprises a first separation chamber provided with an inlet for incoming mixture, a first outlet for the light fraction, and an outlet for an intermediate fraction enriched in coarse particles. A second separation chamber is provided with a second inlet, a second outlet for a light return fraction, and an outlet for separated heavy fraction, the outlet for intermediate fraction being connected to the second inlet leading from a first zone in the first separation chamber. Said zone has a higher pressure than a second zone connected to the second outlet, the second zone being located in the first separation chamber or connected to the latter, the first and second separation chambers thus communicating to form a circuit.

Abstract: The method is intended for separating a flow of pulp containing impurities of coarse particles, partly light and partly heavy particles, by means of a main sieve or the like, into at least one pulp flow and one coarse reject flow. The coarse reject flow is separated by a hydrocyclone separator of a known type into a pulp flow, a light reject flow and a heavy reject flow. Advantageously, the light reject flow is separated by a bow sieve into a flow enriched in light particles and a flow enriched in fibers and which may be returned to the main sieve.

Abstract: The paper-making stock is fed continuously to a tank with two chambers separated by a partition having an opening for passage of stock from the first to the second chamber, evacuation means being provided for maintaining equally low gas pressures in the two chambers. A stock consumer is connected to a stock outlet of the first chamber, and stock from an outlet of the second chamber is returned to the tank via a recycle line. Means for sensing the stock level in the first chamber are provided to control valve means in the recycle line, whereby said stock level is maintained constant.

Abstract: A hydrocyclone separator for separating a materials mixture into fractions with an upper covered cylindrical part and a lower concial part, the upper part having a tangential inlet, and an axial outlet on its cover; the lower part having an outlet at its bottom.A cylindrical shell or mantle surrounds the container to receive leakage. The shell and container form three compartments with individual openings in which are pressure-sensitive or other sensitive indicators to show the presence of leakage.

Abstract: A hydrocyclone chamber includes a cylindrical part having a tangential inlet and a central outlet for a separated fraction of the incoming mixture, the chamber also including a conical part leading to a second outlet for another fraction of the mixture. A guide bar extends circumferentially along the wall of the cylindrical part at least to the inlet orifice and is bent and inclined to give the mixture flowing from said inlet a component of movement directed radially inward and a component of movement directed axially toward said conical part of the chamber.

Abstract: The separation chamber has a circular cylindrical part with a tangential inlet for the mixture and a central outlet for the light separated fraction, the chamber also having a conical part forming an outlet for the separated heavy fraction. A first guide bar on the wall of said conical part gives the heavy fraction a component of movement directed radially inward, and a second guide bar on said wall between the first bar and the heavy fraction outlet gives the heavy fraction a component of movement directed axially toward the light fraction outlet.

Abstract: A hydrocyclone separator has a tangential inlet comprising an inlet nozzle that accepts a mixture to be separated and a diluting liquid. The inlet is at one end of the hydrocyclone and a heavy fraction outlet is at the other end. The inlet nozzle introduces the diluted mixture into the hydrocyclone with a flow component directed toward the heavy fraction outlet. The hydrocyclone has a light fraction outlet at the same end as the inlet.