Dynamic modeling and simulation of continuous airlift bioreactors

For dynamic behaviors of continuous airlift bioreactors, a mathematical mod el based on a tanks-in-series model with backflow has been developed. The e quations describing the dynamics of airlift bioreactors are material balanc es for micro-organism, substrate, dissolved oxygen and oxygen in gas-phase and heat balances. Nonideal mixing of liquid and gas phases is taken into a ccount using a tanks-in-series model with backflow. The batch operation, st artup operation and the consequence of plant failure were simulated and the effects of design and operating parameters for an airlift bioreactor on it s dynamic behaviors were discussed. The concentration profiles of micro-org anism, substrate, dissolved oxygen and oxygen in gas-phase and the temperat ure profile in an airlift bioreactors and their dynamics were obtained. The computational results indicate that the transients of a chemostat in the c ase of bubble column bioreactor are slower compared with those in the case of airlift bioreactor. The proposed simulator is more precise as compared w ith models published previously in the literature and therefore provides mo re reliable and rational examination of continuous airlift bioreactor perfo rmance.