Modelling and Optimisation of Milk Pasteurisation Processes

摘要

This work aims at understanding the optimal operation of milk pasteurization processes. The operating procedure consists of milk heating, followed by heat-exchanger cleaning. The duration-of heating and cleaning stages are the decision variables. A dimensionless dynamic model of a continuous process is presented. The objective function incorporates the value added by pasteurization and the cost of cleaning. The optimal operating policy consists of long heating and short cleaning steps. The heating time, however, cannot exceed a limiting value. Otherwise, the required milk outlet temperature cannot be achieved, or the pressure drop becomes excessive. Additionally, a minimum cleaning time is required to avoid continuous increase of deposit thickness.