Answer to Question #214029 in Chemical Engineering for lisa

Question

After recovering all available sugars from your waste stream, you used a chemostat culture of Corynebacterium glutamicum to convert 12 g L-1 glucose to L-lysine. The steady state process was performed

aerobically in a 50 m3 continuous stirred tank reactor (CSTR). The laboratory based performance data

indicated that the yield of biomass from substrate is Yxs is 0.1 g g-1. From your experience, you know

that you can maximise production in continuous reactor systems by maximising the dilution rate.

1. As you had sufficient performance data, you decide to go to your office to determine the lowest

mean residence time τ you can operate to maximise the growth of Corynebacterium glutamicum.

You further calculate the product yield and maximum product yield at this dilution rate on mass

basis. In your calculations you assumed steady state operation.

Answer 1

The residence time of a fluid parcel is the total time that the parcel has spent inside a control volume (e.g.: a chemical reactor, a lake, a human body).

The residence time of a set of parcels is quantified in terms of the frequency distribution of the residence time in the set, which is known as residence time distribution (RTD), or in terms of its average, known as mean residence time.