Two-Compartmental Model for Incomplete Mixing

Biochemical Engineering


Problem Statement: The following equations describe the biomass and substrate concentrations in a continuous bioreactor with cell recycle operated at steady-state.

   dx/dt = 0 = (m-*D)*x          ... Biomass
   ds/dt = 0 = D*(sf-s) - m*x/Yx  ... Substrate
   where   m = mm*s/(K+s)
           Yx = substrate-to-cell yield coefficient
           D = dilution rate
           sf = substrate concentration in the feed stream
Simulate microbial growth in an incompletely mixed bioreactor by adding a second compartment. The fractional size of the first compartment is a, and d=f/V is the exchange "dilution" rate between two compartments, where f is the flow rate between two compartments and V is the total bioreactor volume.
             +-----------------+
             | Compartment #1  |
  F, sf ---->| a*V  x1  s1      |---> F, x1, s1
             |                 |
             +-----------------+
                |        ^
     f, x1, s1   |        |  f, x2, s2
                V        |
             +-----------------+
             | Compartment #2  |
             | (1-a)*V  x2  s2  |
             |                 |
             +-----------------+

Solution:

Two-Compartmental Model for Incomplete Mixing, Dynamic Simulation


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Biochemical Engineering -- Two-Compartmental Model for Incomplete Mixing
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