IT1049869B - Centrifuging and redissolving crystalline sugar in one operation - ejected crystals sluiced at high pressure in turbulence chamber - Google Patents

Abstract

A mass of fluid and sugar feed continuously from the crystallisers into a continuously operating centrifuge, is separated and redissolved by bringing the ejected sugar into contact with solvent fluid as it leaves the centrifuge. Immediately on passing the top edge of the centrifuge basket the crystalline sugar is subjected to the impact of a solvent fluid from nipples, the jets being directed, as the sugar follows a path, at an angle to it. The high degree of turbulence in the outer chamber formed by the inclined baffle, sets up a cloud of vapour which impinges repeatedly against the chamber sides, and follows the contour to a point where the air, crystals, vapour and already dissolved matter bank up before being forced through a narrow gap and over the rim of a dam and drained off for processing. The concn. of the sugar soln. obtained is maintained at the optimal value by measuring the temp. of the soln. as it drains off. Any deviation from a nominal value registered, generates a control signal for altering the input from the crystallisers and/or the solvent fluid tank, the temps. of the charge and the solvent being kept constant at values differing slightly from each other. The sugar thrown outwards from the rotating basket is redissolved completely within the centrifuge, and a product with a high degree of purity results.