Abstract: An apparatus for extracting floatable minerals from a slurry (3). Slurry (3) is fed into a tank (2) via a feed inlet (25) and agitated and aerated so as to create an upper zone containing froth enriched with the floatable minerals. The agitation and aeration are also regulated to create a lower zone (41) containing a relatively dense or coarse component of the slurry (3), and an intermediate zone (42) containing a substantially less dense or finer component of the slurry (3). The surface froth is progressively withdrawn via a launder (30) thereby to produce a flotation concentrate. Similarly, the relatively dense component of the slurry (3) is progressively withdrawn from the lower zone (41) via a bottom inlet (26), and the relatively less dense of the slurry (3) is progressively withdrawn from the intermediate zone (42) via a side outlet (28).

Abstract: A flash flotation device (1) comprises a tank (2) to contain slurry (3) incorporating minerals to be extracted, a feed inlet (25) for admission of slurry (3) into the tank (2), agitation means (10) to agitate the slurry (3) within the tank (2), aeration means to aerate the slurry (3) whereby floatable minerals in suspension form a surface froth for removal via froth lip (29), a bottom outlet (26) for withdrawal of relatively coarse or dense components of the slurry (3) from the tank (2), and a side outlet (28) to regulate the level of slurry (3) in the tank (2).

Abstract: The invention relates to a filter medium particularly for filtering in a suction drier. According to the invention, the filter medium is manufactured of a material that can be made to oscillate essentially at a standard frequency.

Abstract: The invention relates to a method for cleaning the filter medium in a suction dryer by means of ultrasound in an essentially continuous operation. According to the invention, the ultrasonic beams emitted from at least one ultrasonic oscillator (1, 12, 22, 36) are focused essentially near to the filter surface (4, 14, 25) of the filter medium, advantageously on the filter surface (4, 14, 25) of the filter medium, in order to create at least one ultrasound focusing zone.

Abstract: An apparatus for detaching a filter cake created by a suction dryer from off the filter surface of a filter medium and for an essentially simultaneous treatment of the cake to a form advantageous for further processing. The apparatus comprises a suction dryer (1, 11, 27), a connected filter surface (4, 14, 28) and a basin (2, 13, 27) for the material to be filtered. According to the invention, in the vicinity of the filter surface (4, 14, 28) of the filter medium, there is installed a blowing member (7, 17, 21) with at least one part, the blowing effect whereof can advantageously be extended over the whole width of the filter surface (4, 14, 28) of the filter medium, on which surface the filter cake can be formed.

Abstract: Particle size distribution of a flowing material that is composed of solid particles in a carrier fluid is measured employing a measuring element that comprises first and second measuring members having respective confronting measuring surfaces of predetermined area and a mechanism for causing relative movement of the measuring members toward and away from each other. The area of each measuring surface is at least 0.008-0.5 cm.sup.2 per percent solids of the flowing material.

Abstract: The invention relates to a method and apparatus for dispersing gas into liquid or slurry, which uses a rotatable rotor at least partly submerged in the liquid, and blades connected thereto. According to the invention, the gas to be dispersed is conducted, via a gas conduit (1, 22, 32) to the inside (7, 27, 37) of the rotor (6) and further to the surrounding liquid or slurry through at least one discharge aperture (12, 28, 38) formed in the rotor blade (8, 26, 36) and being adjustable in width.

Abstract: The invention relates to an aerator device where the stator is installed coaxially with the rotor and comprises several flow chutes extending outwards from the stator frame. According to the invention, the flow channel (8) comprises a first part (9) that is closed at the top, and an at least one-part flow chute (10, 12, 16, 20, 22, 24) that is open at the top.

Abstract: The degree of fullness of a rotary mill is determined by measuring the variation in power consumption of the elector motor due to the lifting beams of the mill casing striking material in the mill during rotation of the mill casing.