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

Related Mcqs:

1. 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

2. 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

3. Use of raschig rings in place of crushed stones as packing in packed beds (other things being same) ?

   A. Increases pressure drop, increases surface area
   B. Increases pressure drop, decreases surface area
   C. Decreases pressure drop, increases surface area
   D. Decreases pressure drop, decreases surface area

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. Pressure drop through plate tower as compared to that through packed tower, for the same duty will be___________________?

   A. Less
   B. More
   C. Equal
   D. Either A. or B.; depends on the packing height

6. A packed tower compared to a plate tower for a particular mass transfer operation__________________?

   A. Incurs smaller pressure drop
   B. Allows installation of cooling coils
   C. Is less costly when built in large sizes/diameters
   D. Is more suitable, if suspended solids are present in fluid streams

7. Diameter to height ratio for a raschig ring is_____________________?

   A. 1
   B. 0.5
   C. 2
   D. 8

8. The main reason for dividing a tall packed tower into series of small towers is to________________________?

   A. Minimise the overall pressure drop
   B. Avoid flooding
   C. Reduce liquid hold up
   D. Avoid channelling

9. Under conditions of flooding in packed tower, the gas pressure drop___________________?

   A. Decreases rapidly
   B. Increases rapidly
   C. Remain constant
   D. Is maximum

10. Channelling in a packed tower results from the_____________________?

    A. High pressure drop
    B. Maldistribution of liquid
    C. Non-uniformity of packing
    D. Both B. and C.