A. < 30
B. < 7
C. > 7 20 < 50
Related Mcqs:
- In packed towers provided with saddle packing, liquid redistributors are positioned at every _______________ times column diameter or 6 metres whichever is less?
A. 2-3
B. 5-8
C. 10-15
D. 20-25 - The operating velocity in the absorption tower is usually 40-50% of the flooding velocity. Packed absorption towers are normally designed for a pressure drop of about _________________ mm of water column per metre height of packing?
A. 1-5
B. 20-40
C. 100-150
D. 1000-1500 - In packed towers provided with pall rings liquid redistributors are positioned at heights of every 6 metres or 5-10 times the column diameter, whichever is less. Maximum size of the pall rings should not exceed _______________________ of the column diameter?
A. 1/10-1/15th
B. 1/5-1/10th
C. 1/20-1/30th
D. 1/2 to 1/4th - Liquid redistribution should be done in a packed tower packed with raschig rings every 6 metres or ______________ times the column diameter, whichever is lower?
A. 2.5-3.0
B. 5-7.5
C. 10-12.5
D. 15-20 - Normally, the ratio of the total riser area to the tower cross sectional area (for bubble cap towers of diameter more than 3 ft) is around_______________?
A. 0.4-0.6
B. 0.35-0.75
C. 0.1-0.2
D. 0.55-0.85 - In packed absorption tower, onset of flooding usually occurs at a pressure drop of about ______________ mm of water column per metre height of packing?
A. 25-50
B. 50-75
C. 200-250
D. 750-1000 - In case of saddle packing (e.g., berl and intralox saddles), the maximum size of the packing should not exceed ______________ of the column diameter?
A. 1/5th
B. 1/15th
C. 1/30th
D. 1/50th - Pick out the wrong statement pertaining to the comparative evaluation of performance of the packed tower and the plate tower ?
A. Plate tower is preferred, if interstage cooling is required to remove heats of reaction or
solution
B. Plate tower is preferred over packed tower, if the operation involves liquids containing
dispersed solids
C. The total weight of a dry plate tower is usually much more than that of a dry packed tower
designed for the same duty
D. In operations involving large temperature changes. (e.g. distillation), plate towers are
preferred over packed towers as the packing may be crushed due to large temperature changes - In actual operation of a bubble cap distillation tower, the ______________ at the bottom of the tower is more than that at the top of the tower?
A. Molal flow rate of vapour
B. Vapour molecular weight
C. Pressure and temperature
D. All A., B. and C. - Maximum size of the raschig rings used in a packed tower is about _______________ of the column diameter?
A. 1/10th
B. 1/20th
C. 1/30th
D. 1/50th
