Sterilize a big fermenter
This page is created by using a BASIC program originally written by Henry Bungay and correct by R. Zamora and A. Camillo. The full version of this web site can be seen at http://www.rpi.edu/dept/chem-eng/Biotech-Environ/FERMENT/steriljv.htm (December 1, 2000).
You are to play the part of an engineer in charge of producing a
biochemical by fermentation. There is a problem in the sterilization
procedure because heating the medium and holding it until the contaminating
bacteria are killed also causes destruction of vitamin factors and reduces
yields and profits. Let's assume that you know very little about the theory
of thermal death of microorganisms. Try some empirical testing of
temperatures and times. You know that laboratory people often autoclave media for 30
minutes at 121°C.
Please specify times and temperatures. You may note a discontinuity as you test short times because these are only possible with a continuous sterilizer. The killing and destruction during the heat up and cool down periods of batch sterilization are negligible with a continuous sterilizer that heats the medium up and cools it down very rapidly.
YEARLY PROFIT BASED ON YOUR SPECIFICATIONS. For times less than
two minutes, a continuous sterilizer is used. Times less than
0.1 min (6 s) probably impossible.