ABSTRACT
The aim of the experiment on the bioreactor is to obtain a higher biomass concentration of yeast utilizing different operating modes. The control action includes, among other things, speed of feed-in and feed-out pumps and the period of oscillation of the bioreactor. There are three transducers that can be sterilized attached to the bioreactor: PT-100 RTD for temperature measurement; sensor for pH measurement; and sensor for dissolved oxygen concentration measurement. The sensor signals are amplified, filtered, and converted to proportional 4–20 mA current signals for transmission. Generally, this type of bioreactor is kept in a sterilized room and the process control computer, which may require human attention, is kept in a separate control room away from the bioreactor system. The validity of application of the time delay controller along with the observer system in bioprocess control is demonstrated. The same investigation may be carried out for other fermentation processes.
