Authors: S. Altunta?, H. Hapo?lu
The control of batch bioreactors to maintain the pH at a constant set point is quite different from the continuous system applications, because acid and base simultaneous addition has a strong effect on the closed loop performance which may never reach desired value. While it is most desirable to use approximate models based on the chemistry of the system, this may not always be possible for batch bioprocesses. The present paper discusses usage of a simulator with appropriate input and output data obtained from the real batch bioprocess without control. The real process pH behaviour was simulated by using 7M citric acid flowrate changes in the face of constant base addition. Two time steps predictive control was applied to the bioprocess simulator by coordinating 0.5M citric acid and 0.5M sodium bicarbonate flow rates. The best control weighting factor magnitude was determined. The constant set point following was achieved successfully.