Drying and deposition in a multiphase multicomponent medium: An experimental analysis and a new modelling approach

This paper deals with the drying of a multiphase multicomponent medium, whi ch is initially fluid and contains a solid component, some water and a solu ble component. An experimental approach of the physical phenomena in such a medium during drying is first carried out in terms of water and soluble co mponent transport. In this aim, drying experiments have been realised and l ead to the determination of drying kinetics, time evolution of moisture con tent profiles and soluble component profiles during the drying. These exper iments allow us the proposition of a mass transfer descriptive model. This model is based on a diffusive approach of the convective fluid phase transp ort. Mutual diffusion of the dissolved part of the soluble component into t his fluid phase, deposition process of the dissolved part by crystallisatio n, and shrinkage of the medium during drying are also taken into account. B y using this model and the experimental results. a simple identification of both the time and the spatial average value of specific surface of crystal during drying is performed.