TRANSIENT RESPONSES IN SYSTEMS WITH CELLS IMMOBILIZED WITHIN LARGE-PORE MATRICES

This paper deals with the experimental results and mathematical modell ing of fermentations carried out in systems with cells immobilized wit hin a large-pore matrix. Particular attention is paid to non-stationar y situations occurring in immobilized cell systems. A new model, based on the subdivision of the system into two-interconnected sections, th e bulk and the support, is proposed to help the designer when selectin g the most suitable start-up procedure or the best way to change the s ystem from one steady-state condition to another. The time required to achieve steady-state conditions, as well as the fraction of active ce lls with respect to total immobilized biomass, is also related to the residence time for both immobilized and suspended biomass systems.