Previous papers discussed separately the aspects of models of sugar transport and models of mass and energy transfer in rotary sugar driers. This paper advances both aspects of sugar drier modelling, arriving at a new bulk sugar transport model and a superior mass and energy transfer model. The authors describe how these models are combined in one complete rotary sugar drier model. This model covers all the aspects of sugar drying and rotary sugar drier operation in a computer software package. Results from the model are presented alongside experimental data obtained from a sugar mill drier. Finally, this paper gives a brief description of how the model was used in a feed-forward control configuration to achieve high quality control of sugar temperature and moisture out of a sugar drier.