In this work, a lumped mechanistic model has been developed to describe the heat and mass transfer between solid, gas and bubble phases in a batch fluidized bed dryer. To minimize the computational load, an approximation of the bubble temperature has been made in the model and it is shown that this does not significantly reduce the accuracy of the model. Model parameter sensitivity analysis has indicated that the performance characteristics of a bath fluidized bed dryer are affected not only by the inlet gas superficial velocity and temperature, but also by the features of particle and bubble phases, in particular, the particle and bubble sizes. Experimental validation shows that the proposed lumped dynamic model can be used to predict the particle moisture content and temperature profiles during the drying process in a fluidized bed dryer.