GB741123A - Improvements in or relating to sink-and-float separating apparatus - Google Patents

Abstract

741,123. Washing granular materials. LOGUE, L. H., and BAILEY, R. S. May 25, 1951 [May 25, 1950], No. 12297/51. Class 82 (2) A horizontal rotary drum separator for sink and float separation is divided into coaxial intercommunicating inlet and outlet compartments, the intercommunication being at a level above the outlet means for each of the compartments so that there is no interchange of liquid between the compartments, means being provided in the inlet compartment for lifting sunken heavy material and transferring it to the outlet compartment and means being provided in the outlet compartment for discharging heavy material. A drum 10 comprises compartments 26, 27 each provided with lifters 42, shaped and slotted as in Fig. 5. Solids to be separated are fed into the compartment 26 through the shoot 50 to which separating medium is fed at 65. Floats leave at 62 and sinks are received by the lifters into a transfer trough 69 from which they pass at 74 into the compartment 27. Separating medium of greater density is fed at 83 into the trough 69 and thence into the compartment 27 from which middlings pass at 38a into the shoot 89, sinks being lifted into the outlet trough 69a which is flushed with separating medium. A flexible guard 92 in each compartment prevents floats becoming caught up by the lifters 42. The side 72 of the shoot 69 is formed as a grid and is flexible. In Fig. 6, high ash content coal is fed at 135 into the separator 137, the floats from the first compartment 138 passing to a screen 141 and discharge; middlings floated in the second compartment 139 pass to screens 147, 148, the coarser middlings between are crushed at 151 and returned to the circuit. Sinks pass to the screen 144 and discharge. A similar circuit, without feed back of middlings, for treating iron ore is also described.