EFFECT OF SINUSOIDAL VARIATION OF FEED CONCENTRATION AND TEMPERATURE ON THE PERFORMANCE OF A PACKED-BED BIOLOGICAL REACTOR - A THEORETICAL-STUDY

The performance of a packed-bed biological reactor has been analysed u nder sinusoidal variations of substrate concentration and temperature for zero-order, first-order and Michaelis-Menten kinetics. The model e quations were solved by the method of orthogonal collocation. The resu lts show that the cyclic steady-slate conversion is not affected by cy clic variations in the feed concentration. However, cyclic temperature variations with an amplitude of 20 degrees C significantly decrease t he mean exit concentration for zero-order and Michaelis-Menten kinetic s compared to the constant-temperature case. The approach to cyclic st eady-state conditions is estimated to be somewhat slower for zero-orde r kinetics than for the other kinetic models investigated. We conclude that temperature variations during the day or changes in the performa nce of upstream plant will not adversely affect the performance of a p acked-bed biological reactor.