Lactic acid is produced by a Lactobacillus species cultured in a CSTR. To increase the cel...

Lactic acid is produced by a Lactobacillus species cultured in a CSTR. To increase the cell concentration and production rate, most of the cells in the reactor outlet are recycled to the CSTR, such that the cell concentration in the product stream is 10% of cell concentration in the reactor. Find the optimum dilution rate that will maximize the rate of lactic acid production in the reactor. How does this optimum dilution rate change if the exit cell concentration fraction is changed? [rp = (αµ + β)Ce]

 (Contributed by Professor D. S. Kompala, University of Colorado)

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