Thesis (MTech (Electrical Engineering))--Peninsula Technikon, Cape Town, 2002 / Fermentation is the process that results in the formation of alcohol or organic acids on
the basis of growth of bacteria, moulds or fungi on different nutritional media (Ahmed
et al., 1982). Fermentation process have three modes of operation i.e. batch, fed-batch
and continuous mode ofoperation. The process that interests a lot of control engineers
is the fed-batch fe=entation process (Johnson, 1989). The Fed-batch process for the
production ofyeast is considered in the study.
The considered yeast in the study is the Saccharomyces cerevisiae. It grows in both
aerobic and anaerobic environmental conditions with maximum product in the aerobic
conditions, also at high concentration of glucose (Njodzi, 2001). Complexity of fedbatch
fe=entation process, non-linearity, time varying characteristics, application of
conventional analogue controllers provides poor control due to problems in tuning
individual loops and the process characteristics. The problem for control of the fedbatch
process for the production of yeast is further complicated by the lack of on-line
sensors, lack of adequate models as a result of poorly understood dynamics. The lack
of on-line sensors results in the impossibility of tuning the analogue controllers in real
time. The process for propagation of yeast in aerobic conditions is considered in the
dissertation. The experiments are conducted at the University of Cape Town (VCT),
Department of Chemical Engineering with a bioreactor and bio-controller are
combined in a Biostat ® C lab scale plant (B. Braun Biotech International, 1996).
The bio-controller has built in PID controller loops for control variables, with the
ability to adjust the controller parameters i.e. P, D and I through the serial interface
(Seidler, 1996).
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:cput/oai:localhost:20.500.11838/1122 |
| Date | January 2002 |
| Creators | Mkondweni, Ncedo S |
| Publisher | Peninsula Technikon |
| Source Sets | South African National ETD Portal |
| Language | English |
| Detected Language | English |
| Type | Thesis |
| Rights | http://creativecommons.org/licenses/by-nc-sa/3.0/za/ |
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