GB781503A - Improvements in or relating to a method and apparatus for separating components froma mixture of materials - Google Patents

Abstract

781,503. Electrostatic separators. QUAKER OATS CO. Jan. 26, 1955 [Feb. 1, 1954]. No 2336/55. Class 117 Apparatus for electro-statically and pneumatically separating fibres or laminar materials from granular materials, e.g. asbestos fibres from asbestos rock, comprises a drum electrode 14 provided with radial vanes 17 and rotatable in an enclosure formed by a shield 18 and a sheet metal electrode 13. Crushed asbestos rock fed from a hopper 10 passes over the electrode 13 into the influence of the electrostatic field produced by the negatively charged electrode and vanes 14, 17, the asbestos fibres being drawn out of the mass towards the electrode 14 where they acquire a negative charge, are repelled therefrom, and then attracted to the earthed shield 18. On touching the shield they lose their charge and are again attracted and repelled by the electrode 14. This rapid oscillating movement causes loosening and clearing of the fibres which are carried round by the air stream set up by the vanes 17 and then withdrawn via a suction duct 20; the particles of sand and gangue remaining are drawn off at a shute 21. In' a modification, Fig. 2 (not shown) a separate shute is provided for collection of dense bundles of fibres which are too heavy to be drawn through the duct 20. The electrode fed from the hopper may be rotary or may include a conveyer belt, Figs. 3, 4 (not shown). Further, it may comprise .a conventional air -lift screen Fig. 5 (not shown). Fig. 7 shows how a number of separators are arranged and connected in an asbestos processing plant which also'includes a vacuum system 52, and devices 62, 64 for separating the fibres from the air stream. The apparatus may be used in the recovery of mica or graphite. Specification 519,770 [Group V]; is referred to.