GB1407481A - Ore separation - Google Patents

Abstract

1407481 Separating solid particles T C MATHEWS 23 Aug 1972 [23 Aug 1971] 39306/72 Heading B2H An apparatus for separating first and second types of solid particles, e.g. of an ore, the first type of particles having a particular measurable characteristic, comprises means for moving the two types of particles in a uniform path; a sensing means for detecting the measurable characteristic of particles of the first type and for providing control signals; nozzles forming a plurality of flowing fluid streams; and a plurality of means responsive to the control signals for allowing selective impingement of the flowing fluid streams on the particles of the first type to separate the latter from the particles of the second type and each including an actuator coupled with pivotally mounted arcuate means, the actuator being responsive to a control signal for moving the arcuate means from a non-selection position to a selection position for allowing the selective impingement of the flowing fluid stream from a nozzle on a particle of the first type. The apparatus may be used for separating diamond particles from a diamondiferous ore. In Fig. 2, material from which desired particles having a particular characteristic are to be separated is fed by a belt conveyor 10 into a trajectory plane 12 past sensing means 14 comprising a number of individual sensors. A plurality of actuators 16 are linked to pivotally mounted arcuate tubes 18 which in the non-selection mode are positioned to receive streams of liquid from nozzles 22 and to channel them on to a deflecting plate 24. In this mode the material falls along the trajectory plane 12 and into a receptacle 26. When a sensor observes a particle which it is desired to separate, it generates a control signal which actuates a corresponding actuator 16 which in turn pivots its associated arcuate tube, thereby allowing the corresponding liquid stream to impinge upon the desired particle causing it to be diverted into the receptacle 28. In Fig. 3, the material is fed, e.g. as a slurry, on to an inclined screen type conveyor 30 above which is located the sensing means 14 for the actuation of actuators 34, 36 linked with respective arcuate tubes 18 pivotable about a rod 48 and associated with nozzles 22 whereby desired particles may be deflected from the conveyor into a receptacle 54 by liquid streams issuing from the nozzles and passing through the conveyor to impinge on the desired particles. The measurable characteristic of the desired particles may be the natural radiation emitted by such particles or the radiation emitted by them after they have been treated with fluorescent material and irradiated. The radiation emitted by the particles is detected by electromagnetic wave sensing means electrically connected to electromagnetic actuators. Depending on the measurable characteristic of the desired particles, colour, reflectivity, radioactivity or thermomagnetic sensing means may also be used.