Modeling and control of moisture content in a batch fluidized bed dryer using tomographic sensor

In this paper, the modeling and control of the moisture content of the particles in a batch fluidized bed dryer are studied. First, a lumped mechanistic model is developed to describe the heat and mass transfer between solid, gas and bubble phases and experimental validation shows that the model can be used to predict the particle moisture content and temperature profiles during the drying process in the bed dryer. By validating the model both with and without an insulator on the wall of the dryer, it is shown that the wall temperature has a major effect on the process. Feedback control of material moisture content in a bed dryer is studied with tomographic sensors included in the control loop. A controller is designed to achieve a desired drying rate for wet materials. Simulations show that it is possible to control the drying rate.