GB1410201A - Centrifugal ore concentration - Google Patents

Abstract

1410201 Centrifugal ore concentration D C DERINGER 8 Nov 1972 [13 Dec 1971] 51463/ 72 Heading B2P An ore is concentrated by feeding a slurry of the ore through a hollow helicoidal member rotating about its longitudinal axis, whereby a density distribution of particles in the slurry is formed across the width of the interior of the member, and a fraction of the slurry containing concentrated ore particles is tapped off from the outer periphery of the interior of the member whilst the latter is rotated. An ore concentrator, Fig. 1 comprises a pump 12, preferably of the pulsating type, which feeds the ore slurry under pressure via a surge chamber 42 to the upper end of a hollow shaft 26 which is rotated by a motor 54 through a belt and pulley arrangement. Alternatively the slurry may be fed to the shaft by gravity. The shaft 26 consists of sections 48, 116, 114, 118 and 62. The section 114 is in the form of a frusto-conical drum Fig. 4, which does not communicate with the sections 116 and 118 and which carries a hollow helicoidal member 88 to form a centrifuge subassembly 44. The slurry flows through an opening 122 in shaft section 116 via a curved tube 126 to the interior of the member 88 where fractionation of the particles take place by centrifugal force. The member 88 may be in the form of a helicoidal tube but preferably it comprises a plurality of hollow ceramic blocks 140 of trapezoidal cross-section, Figs. 5 and 6, each having a triangularly shaped opening 142 therein, the openings 142 defining a helicoidal passage 94 when the blocks are connected in end to end relation by a cable or rod extending through aligned openings 150 through the wall of the blocks. The blocks are wrapped with glass fibre tape 152. At one or more points along the inner periphery of the passage 94 there is provided a flow-divider 132, Fig. 5, which deflects an outer branch of the slurry stream containing ore concentrate into a discharge branch 134 connected by a tube 90 (92) rotatable with the member 88 to a compartment 76 (78) of a concentrate launder subassembly 68 secured to the frame 30 of the concentrator. The inner branch of the slurry stream containing the tailings is discharged via a drain tube 96 which is connected to the outlet end of the passage 94 in the member 88 and which opens into a tailings launder 98 secured to the frame 30. Water from a line 40 may be fed via a stuffing box 34 to the interior of the shaft sections 62, 118 and through a supply line 112 helically arranged around the drum 114 and enters the passage 94 in the member 88 in the same direction as the slurry via tapping tubes 120a. 120b, 120c, connected between the line 112 and the member 88. The water may be used to dilute the slurry or for introducing additives therein. Alternatively a solvent may be introduced through the line 112 if blockage of the passage 94 occurs.