Minimum possible diameter of a packed column is decided mainly by the________________________?

Related Mcqs:

1. Inside the distillation column, the________________________?

   A. Driving force for the vapour flow is the pressure drop
   B. Liquids are not always at their bubble points
   C. Pressure increases gradually from bottom to the top of the column
   D. None of these

2. Packed column distillation is limited to the column _____________ metres?

   A. Height < 6
   B. Diameter < 0.6
   C. Both A. & B.
   D. Neither A. nor B.

3. In a moderately sized packed absorption tower, channelling (which is most severe with stacked packings) can be minimised by taking the ratio of tower diameter to packing diameter ?

   A. > 4 :1
   B. < 8 : 1
   C. > 8:1
   D. < 6:1

4. The reason for preferring packed towers over plate towers in distillation practice is that the packed tower operation gives___________________?

   A. Low pressure drop and high hold up
   B. High pressure drop and low hold up
   C. Low pressure drop and low hold up
   D. High pressure drop and high hold up

5. At the same gas flow rate, the pressure drop in a packed tower being irrigated with liquid _______________ that in dry packed tower ?

   A. Is greater than
   B. Is lower than
   C. Is same as
   D. Cannot be predicted as data are insufficient

6. According to the Fenske equation, what will be the minimum number of plates required in a distillation column to separate an equimolar binary mixture of components A and B into an overhead fraction containing 99 mol% A and a bottom fraction containing 98 mol% B ? Assume that relative volatility (αAB = 2) does not change appreciably in the column ?

   A. 5
   B. 9
   C. 12
   D. 28

7. In a forced draft cooling tower, water is cooled from 95 to 80°F by exposure to air with a wet bulb temperature of 70°F. In this case, the________________________?

   A. Range is 15°F
   B. Approach is 10°F
   C. Both A. & B.
   D. Neither A. nor B.

8. With increase in the liquid flow rate at a fixed gas velocity in a randomly packed counter current gas-liquid absorption column, the gas pressure drop___________________?

   A. Decreases
   B. Remains unchanged
   C. Increases
   D. Decreases exponentially

9. In a packed bed absorption column, the channelling will be noted by the ____________________?

   A. Increase in flow rate
   B. Sharp drop in pressure drop
   C. Sharp rise in pressure drop
   D. None of these

10. Diameter of raschig rings used in packed tower in industry is normally around _____________________ inches?

    A. 2
    B. 8
    C. 12
    D. 18