GB1332121A - Separation of particulate materials - Google Patents

Abstract

1332121 Wet separation of solids FLOATEX SEPARATIONS Ltd 5 Oct 1970 [3 July 1969] 33607/69 Heading B2H An apparatus for separating a less dense particulate material, e.g. coal, from admixture with a dense particulate material, e.g. sand, comprises a tank 1 having all of its sides vertical and in which the mixture is passed into an upwardly flowing current of water and a surrounding water manifold 8 feeding a set of spaced parallel perforated pipes 9 extending across the base of the tank. The perforations in the pipes 9 may face upwards or downwards. The tank which is square is horizontal cross-section is surrounded at the top by an overflow launder 3 and is provided at its base with a conical or pyramidal collector 2 at the bottom of which are an anti-vortex plate 10 and an auxiliary water supply 11. A feed well 4 fed through a tangential pipe 5 with a suspension of the materials to be separated has at its open base two baffle plates at right angles to each other to destroy the circular component of velocity of the in-feed material. An auxiliary water supply 6 is provided for de-agglomerating residual heavy material present in the collector at starting. A pressure sensitive device 7 controls the pulp density in the tank by the control of a valve 12 for the discharge of denser material and of a secondary water supply to the tank. In operation, the materials to be separated fall from the feedwell 4 into the water in tank 1 where the upward current is relatively weak and does not convey light material to overflow. Instead, a gradient of specific gravity is set up in the tank, the light material by virtue of its lower specific gravity being displaced to the top for overflow into the launder 3 and the heavy material settling down and passing, through the spaces between the pipes 9, into the collector 2. Flow diagrams of plant using the separating apparatus are described.