Comparison of evaporator stations with and without pre-evaporator

Two sugar factories with a processing capacity of 6000 t/d of beet and falling film type evaporators in all effects but differing in the lay-out of the evaporator station were compared. A five-effect station with serial juice flow from effect 1 to 5 was compared with a five-effect station, where the thin juice is fed into the 4th effect (pre-evaporator), and then after additional heating to the 1st effect. For the two sugar factories identical process parameters and identical technological equipment were assumed. It was found that the use of a pre-evaporator gives significant operating benefits to the operating of the evaporation station, which may support decision of its application despite the higher installation costs compared to the station without pre-evaporator.

Key words: evaporation, pre-evaporator, heat economy