Progressive freeze concentration is an alternative method to concentrate aqueous industrial streams compared to evaporation or membrane separation. In this research sucrose and maltodextrin solutions were concentrated in a stirred progressive freeze concentrator. The solute inclusion in the formed ice was studied using varying stirring speeds, initial concentrations and freezing plate temperatures. Under constant freezing plate temperature, a lower limit was found for the solute inclusions with increasing stirrer speeds. To improve the freeze concentration process, a decreasing temperature ramp was applied to the freezing plate. This yielded 2 to 3 times less solute inclusions in the ice, while maintaining similar ice yields.
- Freeze concentration
- solute inclusion