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
Related Mcqs:
- Plate towers are preferred to packed towers, when large temperature changes are involved, because of the reason that the____________________?
A. Packing may be crushed due to thermal expansion/contraction of the components of the
equipments
B. Pressure drop in the equipment will be very high
C. Viscosity variation of the fluids may cause channelling/flooding
D. None of these - 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 - 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 - 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 - 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 - Use of packed towers for distillation is generally limited to the__________________?
A. Small sizes
B. Multi-component distillation
C. High pressure operation
D. Vacuum distillation - Use of packed towers for distillation is generally limited to the____________________?
A. Small sizes
B. Multi-component distillation
C. High pressure operation
D. Vacuum distillation - 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 - In a packed tower, the value of HETP equals HTUOG, when the equilibrium and the operating lines are (where, HETP = height equivalent to a theoretical plate HTUOG = overall gas phase height of a transfer unit) ?
A. Straight
B. Parallel
C. Both A. & B.
D. Neither A. nor B. - Can the efficiency of a plate in the distillation tower be greater than 100% ?
A. Yes
B. Normally not; but is possible if infinite number of plates are put
C. Never
D. Yes; if the reflux ratio is maximum
