The modelling of crystallisation schemes in a raw sugar factory

This paper reviews crystallisation processes and describes the development of mass/energy flow models to predict the changes in process equipment requirements and estimate benefits in sugar quality due to the adoption of new crystallisation schemes. Modelling with multiple spreadsheets is shown to be very effective, enabling dynamic linkages between a base raw sugar pan stage mass/energy model, a high grade fugal model, a colour partitioning model, a process equipment capacity model, and an equipment cost model. Results are shown indicating that sugar and crystal colour are improved by more remelt of intermediate sugars, and the extent to which process equipment has to be expanded to implement such schemes. Other results are given to quantify process equipment capacity changes to accommodate production of high purity raw sugars and of remelt/recrystallisation sugars.