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
Related Mcqs:
- 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 - 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 - 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 - 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. - For experimental determination of mass transfer co-efficient by wetted wall tower, the mass transfer area is___________________?
A. Calculated
B. Unknown
C. Known
D. Not required - 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 - H2S is being absorbed in a gas absorber unit. The height of the transfer unit based on the overall mass transfer coefficient on the gas side is 0.4 m. The equilibrium data is given by, y = 1.5 x. The bulk concentration of H2S has to be reduced from 0.05 to 0.001 mole fraction in the gas side. The height of the tower (in meters) corresponding to an operating line given by, y = 5x + 0.001 is ______________________?
A. 2.0
B. 1.56
C. 1.0
D. 0.56 - For the gas absorption, the height of a transfer unit, based on the gas phase is given by (G: superficial molar gas velocity, L: superficial molar liquid velocity, FG: mass transfer co-efficient, moles/m2, a: interfacial area per unit volume of tower) ?
A. G/(FG . a)
B. FG/(G . a)
C. (G . a)/FG
D. L/(FG . G) - According to the film theory of mass transfer, the mass transfer co-efficient is proportional to (where, D = molecular diffusivity) ?
A. D
B. D2
C. D0.5
D. 1/D - JD factor for mass transfer is a function of Reynolds number. Mass transfer by molecular diffusion from a single drop to surrounding still air is given by___________________?
A. Nsh = 2
B. Nst = 2
C. Nsc = 2
D. None of these
