GB977128A - Improved method and apparatus for forming solid granules - Google Patents

Abstract

<PICT:0977128/C1/1> <PICT:0977128/C1/2> <PICT:0977128/C1/3> Organic and inorganic salts are granulated by passing them in a molten state through a coolant 10 in the vapour phase and subsequently into the coolant 10b in the liquid phase, the coolant being at a temperature in the liquid phase below the melting point of the material and contained in an enclosed zone. The molten material is fed to a heated container 2 from which it falls through perforations in a vibrated plate 3 into the coolant, and the granules so formed pass along a conveyer 15 and elevator 16 to a screen 20 to be dried and classified. The liquid may also be divided by passing it through two identically perforated plates, one rotating above the other (Fig. 5, not shown), or, by oscillating solid rods 47 in and out of holes in the plate 3, Fig. 8, or, by oscillating hollow rods 53 with apertures 54 so that the liquid passes through the apertures 54 only when they are above the holes in the plate 3, Fig. 11. The vapour 10 is liquefied by passing it through an air-cooled condenser 13 and it re-enters container 8 along pipe 25. To ensure that the coolant has no contact with the atmosphere the liquid at the top of the elevator 16 may be covered by a lighter and less volatile liquid 17.