A. Leads to high tray efficiency
B. Results in higher pressure drop per tray
C. Both A. & B.
D. Neither A. or B.
Related Mcqs:
- In a distillation column, bubble caps are located on trays with a pitch of ______________ times the outside diameter of the caps?
A. 1.3 to 2
B. 1.6 to 2
C. 2.5
D. 1.5 to 3 - In distillation columns, bubble caps are held in place over trays by ________________?
A. Rivets
B. A hold down bar
C. Bolts
D. Both B. and C. - Pick out the wrong statement pertaining to the use of valve tray, seive tray and bubble cap trays in continuous distillation column ?
A. Bubble cap trays though most expensive are the best in situations, where low vapour rates is to be handled and a positive liquid seal is essential at all flow rates
B. Murphree efficiency of all the three trays are nearly equal, however the peak efficiency is generally higher for sieve and valve trays than the bubble cap
C. Maintenance cost for valve and sieve trays are comparatively more than bubble cap tray due to their relatively complicated construction features
D. Valve trays have the highest turn down ratio (i.e. the ratio of the highest to the lowest vapour flow rates) and thus provide the maximum flexible operating range - Hole diameter of the sieve trays in the distillation column ranges from ______________ mm?
A. 1 to3
B. 4 to 8
C. 3 to 12.5
D. 12.5 to 18.5 - The length of straight rectangular weir used on cross-flow trays is generally ________________ the column diameter ?
A. 0.6-0.8 times
B. Equal to
C. Twice
D. 2 ft irrespective of (for column > 3 ft diameter) - What is the value of ‘q’ for saturated vapor feed to a distillation column? (where q = fraction of the feed stream that is liquid ?
A. 0
B. 1
C. 1 - What is the slope of the feed line, if the feed to a distillation column is a saturated liquid ?
A. 0
B. ∞
C. > 1
D. < 1 - Height equivalent to a theoretical plate (HETP) is the height of packing that will give the same separation as one theoretical plate in gas-liquid mass transfer operations like distillation, absorption/stripping and humidification/dehumidification. HETP which is experimentally determined, depends upon the_______________?
A. Flow rates of each fluid
B. Type and size of packing
C. Concentration of each fluid
D. All A, B. & C. - The slope of the feed line in distillation operation is given by (where, q = fraction of the feed stream that is liquid ?
A. -q
B. -q/(1-q)
C. -q/(q-1)
D. None of these - In a distillation column, the minimum residence time for liquid in the downspout is about ______________ seconds?
A. 1
B. 8
C. 80
D. 180