Effect of Freezing Time and Shaking Speed on the Performance of Progressive Freeze Concentration via Vertical Finned Crystallizer

Abstract

Performance of a newly developed freeze concentrator named Vertical Finned Crystallizer (VFC) in concentrated glucose solution was evaluated. The VFC was designed as an attempt to provide an efficient Progressive Freeze Concentration (PFC) system by providing larger heat transfer area for crystallization. Glucose solution at an initial concentration of 11°Brix was concentrated through the new PFC system. The performance of the crystallizer was analyzed in parallel with the effect of freezing time and shaking speed to the system efficiency, represented by effective partition constant (K) and solute recovery (Y). The results show that the efficiency of the system has significantly improved portrayed by the lowest K value obtained of 0.383 and the highest Y value obtained of 0.96 g glucose/g initial glucose at intermediate circulation time and shaking speed. Thus, the VFC is evidently proven to have a high potential to be integrated in a PFC process as an efficient concentration system. The results obtained offer some guidelines on how to produce an efficient PFC system through parameter setting.