DESIGNING DRYERS USING HEAT AND MASS-EXCHANGE NETWORKS - AN APPLICATION TO CONVEYOR BELT DRYERS

Classical 1-D numerical simulations of dryers involve the solution of non linear differential relations which include balance equations and transfer functions: namely, the drying rate equation and the heat tran sfer equation. These relations are integrated by means of the network theory and a new approach - the Number of Transfer Units method. This process leads to a non-linear algebraic system used to develop compute r simulation programs. In this pager, the applications are based on th e study of multiple-conveyor dryers. This type of dryer is used for ma ny chemical engineering industrial applications to dry coarse particle s (i.e., over 5 to 10 mm) or for fond engineering, Numerical simulatio ns are performed to analyse the drying efficiency of these conveyor dr yers. Due to the heat and mass numbers of transfer units and to the ne twork idea, the computer programs run faster than classical ones. This program is involved in the expertise and study of the effectiveness o f multiple-conveyor dryers, Some rules of behaviour of conveyor dryers are discussed and may be used in order to improve their design.