Dynamic Simulation and Control of Microbial Cell Population in Continuous Bioreactors

Continuous bioreactors are critical unit operations in a wide variety of biotechnological processes. Due to the level of detail built in their mathematical formulation, cell population balance models represent the most accurate way of describing the microbial population heterogeneity in continuous bioreactor. In this work,the equation set of the model was solved numerically using rigorousspace–time conservation element and solution element' CE/SE method.MATLAB/Simulink pre-existing blocks are used for modeling and control of the different moments of cell mass distribution in a continuous bioreactor. For investigating the efficiency of automatic controller, 10% increase in maximum specific growth rate in Ks, was considered. The set point for zeroth, first and second moments of distribution were taken to be; M0,sp=0.6706, M1,sp=0.1541, M2,sp=0.0505, which correspond to a dilution rate of 0.953 h-1 and 0.6 h-1. In the first case the controller response after 10 hours was (0.92 h-1 ±. 05), (0.87 h-1 ± 0.4) and (0.92 h-1 ± 0.2). For the second case the controller response was close to set point(0.6 h-1 ±. 001) after 20 hours.