Abstract: The present invention relates to a method pertaining to press filters of the kind which include a plurality of press plates that can be brought towards and into mutual abutment and pairs of which form therebetween at least one pressure chamber, wherein there is formed in each pressure chamber as the aqueous suspension of solid particles is dewatered a filter cake which upon completion of the dewatering process is released from the chamber by separating the press plates so that the chamber will empty itself of its contents. The method is characterized in that emptying of the pressure chambers is achieved by permitting each press plate to rotate freely and swing about an axis which extends generally horizontally through the plane of the plate, under the influence of the released filter cake. The press filter is constructed so that each press plate is able to pivot in relation to the rails.

Abstract: A method which pertains to the separation of pulp which contains magnetic constituents in a wet-magnetic, low-intensity separator of the concurrent type, in which a cylindrical, horizontally mounted rotatable drum coacts with non-rotating magnets disposed in the drum in a manner to convey magnetic constituents in contact with the drum surface to an outlet for magnetic concentrate, and in which method pulp which is depleted of magnetic constituents is separated as waste at a region remote from the concentrate outlet in a direction opposite to the direction in which the drum rotates. Additionally, pulp is delivered to the separator so as to bring the pulp into contact with the drum at or close to the highest level of the drum; water is delivered to the separator in the vicinity of the concentrate outlet such that water will flow in contact with the pulp constituents that accompany drum rotation; and water is removed from the drum together with the waste. A wet-magnetic separator is also set forth.

Abstract: The invention relates to a method for finely grinding minerals and similar materials in an essentially dry state to particle sizes at which the ground material can be used as a filler. The method is characterized by effecting at least the final grinding phase in a closed grinding cavity that has been placed under a sub-pressure. The pressure in the grinding space shall preferably be lower than the prevailing ambient pressure by up to about 10 kPa.The invention also relates to a mill having a grinding cavity that can be placed under a sub-pressure.

Abstract: The present invention relates to a method and an arrangement for finely-grinding minerals and similar material intended for use as filler material to a particle size appropriate for this purpose, with a mill which operates by agitating grinding medium and in which the material is ground in a substantially dry state. The invention is characterized by predetermining the stay time of the material being ground in the mill; maintaining the predetermined stay time partly by discharging ground material from the mill at a predetermined, essentially constant rate, and partly by adjusting the infeed of material to the mill in relation to the quantity of material discharged from the mill by the amount of material present in the mill increases during the infeed of material thereto; and by interrupting the infeed of material to the mill over a predetermined short period of time when the material reaches a predetermined highest level in said mill.

Abstract: The invention relates to a method for thickening and clarifying fine particle suspensions, wherein the suspensions are thickened and clarified in combination with a back-pulse filtration process. The method is characterized by partially submerging one or more filter modules in the fine particle suspension concerned, in open vessels or reservoirs. The suspension is back-pulse filtered in these open vessels or reservoirs with the aid of the filter modules. The invention also relates to a filter module which includes one or more parallel working, vertical hollow-tubular filters, and a device for delivering liquid and optionally air to the filter module and removing the liquid and air therefrom during filter operation, this device being common to all filters. The filter module is characterized in that the filters are mounted in a plate and that the plate is covered by an easily opened lid which, when closed, seals against the plate.

Abstract: The invention relates to a method for dewatering particle collections with the aid of a filter press in a cyclic sequence comprising filling, dewatering and emptying stages. The various stages within each cycle and between consecutive cycles are followed-up and determined by measuring continuously a magnitude which varies with the mass of the press and its contents, preferably the pressure exerted by the press and its contents on the surface supporting the press.

Abstract: The present invention relates to a method of and apparatus for pressure filtering, the pressure filter (1) used comprising pressure plates (3,4,5,6), which can be pressed against each other. Pressure chambers (8) are formed between the pressure plates and in each one of the pressure chambers two substantially vertical filter cloths are mounted. In order to loosen the filter cakes (32) from the filter cloths (9), means are used to produce sudden acceleration forces, e.g. directly or indirectly acting blow devices (34,36,38) or blow devices or lifting means, cooperating with stop surfaces, which devices and means are designed to drop the guide rails (12) from a lifted position, and/or shear forces, e.g., devices to displace the lower ends of the filter cloths in respectively opposite directions in the planes of the cloths.

Abstract: The invention relates to apparatus for grinding mineral products and similar hard materials with the aid of a grinding medium agitated by a pin-equipped rotor, and is characterized in that the pins are manufactured of cemented metal carbide.

Abstract: The present invention relates to a method for dewatering water-containing particle collections with the aid of gas under pressure, in which at least one of a possible multiple of stages is effected with the aid of gas to which a pressure difference is imparted through and across the particle collection. A smallest predetermined pressure difference is created and the time for establishing the pressure difference does not exceed appreciably the time taken for gas penetration of the therewith dewatered particle collection to occur.

Abstract: Method and apparatus for pressure filtering in a pressure filter (1) comprising a frame carrying press plates (3-6), which can be brought together and apart, said press plates between themselves forming pressure chambers (8). In each pressure chamber there are two filter cloths (9) forming a filter element, said filter cloths being connected to each other in one piece and hanging down from a suspension rod (58) resting on guide rails (86). During operation a suspension of solid particles in a liquid is introduced between the filter cloths (9) in the pressure chambers (8). The liquid is pressed through the filter cloths (9) under the influence of membranes (7) loaded by a pressurized medium and by blowing through a gas and is removed through drain channels (10, 12, 14). The filter cakes (40) remaining between the filter cloths (9) are discharged after bringing apart the press plates (3-6) by vibrating (98) of the filter cloths (9).

Abstract: A device in a peristaltic pump of the type including at least one pressure body (8) driven along a circular path, there being disposed concentrically around at least the major portion of this path a support structure (9, 10) accommodating an elastic hose (11) which is subjected to a local compression against the support structure by means of the pressure body as this body moves along its circular path, and an annular member (12) placed between the pressure body (8) and the hose (11), with its inner circumference abutting against the pressure body and its outer circumference abutting against the hose, towards which the annular member is locally pressed by the pressure body. The primary characteristic feature of the inventive device is a non-return valve (15) acting adjacent the end of the hose (11) connected to the pressure outlet (16) of the pump, at least part of the outer circumference of the annular member (12) together with the pressure body (8) constituting the operating means for this valve.

Abstract: This invention relates to a method in the operation of magnetic separators comprising a plurality of canisters or like devices (4) containing magnetizable induction poles (41) arranged to pass through a magnetic field (1). While the canisters (4) are located in the magnetic field (1), a particle suspension is supplied (5) to the canisters, in which magnetizable particles are attracted to the induction poles (41). Rinsing fluid (6) may optionally be supplied to the canisters while the canisters are still located within the magnetic field (1), thereby to remove non-magnetic particles through discharge means (7a, 7b) for fluid and non-magnetic material. Outside the magnetic field flushing fluid is supplied in a flushing station (8, 56), this flushing fluid removing magnetic material through discharge means (8, 57) for magnetic material. The canisters (4) are provided with flexible sealing lips (36) as disclosed in U.S. Pat. No.

Abstract: A dynamic dense media separator, comprising a cylindrical separation vessel with an axial outlet--float outlet--for separated material fractions of a lower density together with dense media, an outlet on the cylindrical surface of the separation vessel--a sink outlet--for separated material fractions of a higher density together with dense media, and either an inlet on the cylindrical surface of the separation vessel for dense media as well as material to be separated, or such an inlet only for dense media, and an axial inlet for material to be separated together with a minor portion of the dense media. Of the two outlets and inlets situated on the cylindrical surface of the separation vessel, at least the outlet has the shape of an involute connection piece which at least partially surrounds the separation vessel and is bent essentially in the direction of the circumference of the vessel.

Abstract: The present invention relates to a device for tanks of circular type, such as for example thickeners, sludge tanks, mixing tanks and the like, in which at least one scraper arm, mixing arm or the like is journalled, as well as mounted in the center of the tank so as to be raisable and lowerable, and in which there are drive means capable of imparting a sweeping motion to the arm and its scrapers over the bottom of the tank. According to the invention an element is arranged extending between the periphery of the tank and its center, which element is longitudinally movable in relation to the periphery of the tank and is sufficiently rigid to be capable of transferring active or reactive forces to an extent at least corresponding to the torque of the scraper-carrying arm or the like.

Abstract: This invention pertains to a method for removing small impurity particles and dissolved substances from an aqueous dispersion or pulp slurry. The invention in particular pertains to a method for deinking of newsprint. In its most general aspect the invention relates to removing of dissolved substances, preferably organic substances and small impurity particles from an aqueous dispersion.