BIO PROCESS ENGINEERING Question Papers (Regular, 2007)

SET : 1

1. Mention about the regulatory constraints of bioprocess.

2. a) Briefly explain about the materials of construction for fermentor fabrication.

b) Explain different types of agitators used in fermentors.

3. Describe in detail the theory of oxygen requirement and supply in industrial fermentation.

4. A medium containing a vitamin is to be sterilized. Assume that the number of spores initially present is 100000/liter. The value of activation energy for the death of the organism (E_od) and pre – Arhenius constant for the spores are

Pre – Arhenius constant = 1 × 10³⁶ /min

E_od = 65 kcal/g – mol

For the inactivation of the vitamin, the values of

E_od = 10kcal/g – mol

Pre – Arhenius constant = 1 × 10⁴ /min

The initial concentration of the vitamin is 30 mg/lit. compare the amount of active vitamin in the sterilized medium for 10 litre and 10,000 litre fermenters when broth is sterilized at 121 C when we require in both the cases thet the probability of an unsuccessful fermentation be 0.001. ignore the effects of heat up and cool – down periods.

5. Determine the rate of oxygen consumption and yield coefficients if ate of growth at exponential phase is r_x = 0.7 gdw/l-h in a batch reactor of 5000 litres volume with the growth of yeast on glucose as per the equation given

C₆H₁₂O₆ + 3O₂ + 0.48NH₃ --------------- 0.48C₆H₁₀NO₃ + 4.32H₂O + 3.12CO₂

Final yeast concentration of 50 gdw/l is required.

6. Enumerate the aerobic catabolism of glucose with emphasis on energetics.

7. Explain the role of following parameters on the growth kinetics :

a) Temperature

b) Dissolved oxygen

c) pH

Enumerate the difference between the substrate and product inhibition on product formation with examples.