High grade sugar recovery using a continuous centrifuge : final report BSC25

Abstract

This project report describes the conversion of an existing batch high grade centrifuge to a continuous unit (termed a hybrid fugal) and an assessment of its performance characteristics.

It has been established that the continuous version of the fugal is capable of processing both A and B massecuites at higher rates than in its previous batch configuration. Massecuite rates of up to 38 t/h were recorded with the hybrid fugal. Power requirements were almost half those of batch machines and the molasses purity rise was on average 2.2 and 1.1 units for A and B massecuites respectively. The hybrid fugal consistently produced Brand 1 sugar of quality comparable to batch machines but Very High Pol sugar was more difficult to produce. Although experimental trials have not been performed with the hybrid fugal producing Brand JA sugar, it is expected that the machine could easily adapt to this process constraint. Crystal breakage and lump form.('l.tion in the sugar were found to be the main operating problems associated with the hybrid fugal.

The report makes a number of recommendations to improve the operational performance of the hybrid machine. An economic analysis is also presented which clearly demonstrates the economic advantages of a hybrid fugal, incorporating the suggested modifications, balanced against a batch machine.