SE322188B - - Google Patents

Abstract

1,134,864. Classification of solids. INSINOORITOIMISTO ENG., BUREAU R.T. HUKKI. 17 Feb., 1966, No..7042/66. Headings B2H and B2P. A multiple step, quality control section for connection to a pneumatic or hydraulic separator comprises an outer shell made up of coaxial,; superimposed, cylindrical rings 11 -Fig. 4, each having a skirt-like inward extension 13, an inner core made up of coaxial, superimposed, conical core pieces 5 each having an inner conical extension 7, Fig. 2, provided with one or more slots 9 communicating with a central opening 8, and a top piece 1 having a conical base portion and an upper tubular portion 3. The rings 11 are clamped between flanges 18, 19 and each ring may be provided with one or more tangential inlet means 14 for the wash medium opening in the annular space below the extension 13. The core pieces 5 are each provided with one or more lugs 10 and are supported by the lugs 10 on the lowermost core piece resting against the extension 13 of the lowermost ring 11 and by one or more lugs 4 on the top piece 1 engaging under the extension 13 of the uppermost ring 11. The parts 1, 5 and 13 are preferably made of rubber. The control section may be connected to the seperator by a flexible joint so as to be vibrated. In operation, the rotating coarse fraction from the separator enters in helical manner into the downward leading, zig-zagging space between the rings 11 and the core pieces 5 and spreads out into skirt-like annular layers. Wash medium admitted through the inlets 14 is forced across the layers and carries with it fines towards inclined channels 15, formed by the slots 9 in one core piece 5 with an adjacent core piece, and discharges into the central tube 16 constituted by the openings 8 in the core pieces 5 and the tube 3. The coarse fraction resisting the washing action of the medium continues its helical motion and discharges at the bottom of the section. In a hydraulic classifier 22, Fig. 5, equipped with a quality control section 23 for the coarse fraction, a suspension of solids to be classified is fed via a pipe 25 and a tube 26 on to a distributor plate 28 mounted on a rotating shaft 27 which also carries an impeller 30 and an ejector 31. The suspension is whirled by the impeller 30, the fine fraction discharging upwards via whirl-arresting vanes 34 into a launder 36. The coarse fraction passes downwards into the section 23 where it is washed by water fed from a tank 37 via control valves 30 and the inlet pipes 14. Wash water and entrained fines pass up the tube 16 and the impeller hollow shaft 29 and are sprayed by the ejector 31 below the curtain of in-coming suspension and are discharged upwardly with the fine fraction. The washed coarse fraction enters a cone 32 and is discharged via a valve 33.