Modeling and Simulation of a Co-Current Rotary Dryer Under Steady Conditions

A model which joins the overall design algorithm of a rotary dryer with the drying kinetics equations derived from experimental data and with a finite segment algorithm is implemented in order to verify the dryer dimensions obtained from a basic sizing procedure. Total energy and mass balances and well-known correlations for the overall heat transfer coefficient are employed to develop it. Moreover, a one-dimensional finite segment model is solved to obtain the length profiles of temperature and water content for the air and solid phases. An experimental correlation for the mass transfer coefficient between solid and air phases is included in the finite segment model. The chosen heat transfer unit number for the basic sizing is verified with the outlet temperature and water content calculated by the finite segment scheme.