Search
.Management Sciences
Category: Process Equipment and Plant Design
A cylindrical pressure vessel of volume 6 πm3 has to be designed to withstand a maximum internal pressure of 10 atm. The allowable design stress of the material is 125N/mm2 and corrosion allowance is 2 mm. The thickness of the vessel for a length/diameter ratio of 3 will be close to________________?
A. 5 mm
B. 6 mm
C. 8 mm
D. 10 mm
Liquid gradient over a tray can be minimised by________________?
A. Providing a higher skirt clearance or a higher weir
B. Decreasing the number of rows of caps through which the liquid flows or by decreasing the
velocity of liquid flow past the caps or by reducing the distance along the tray through which
the liquid must flow
C. Using split flow, radial flow or cascade flow for column diameter large than 4 ft
D. All A., B. and C.
The stress developed in a material without any permanent set is called the____________________?
A. Ultimate stress
B. Yield stress
C. Elastic limit
D. Breaking stress
In most of the shell and tube heat exchangers, the tube pitch is generally ______________ the tube diameter?
A. Less than
B. 1.25-1.50 times
C. 2.5 times
D. one-fourth of
Steam economy is defined as the amount of evaporation per unit amount of steam used, while the capacity is the total evaporation obtained per hour. Use of multiple effects in evaporation ?
A. Increases capacity
B. Increases economy
C. Does not affect the capacity
D. Both B. & C.
In a shell and tube heat exchanger, the clearance of the tube is generally___________________?
A. Not less than one-fourth of the tube diameter or 3/16″
B. More than the tube diameter
C. Equal to the tube diameter
D. More in case of triangular pitch as compared to the square pitch tube layout
Vapor velocity in a distillation column for non-foaming mixture is in the range of ______________ times the flooding velocity?
A. 0.1 to 0.3
B. 0.6 to 0.7
C. 0.85 to 0.95
D. 1.5 to 2
Pick out the wrong statement?
A. If sufficient residence time (around 8 seconds) is not provided to the downcoming liquid in
the downcomer, it may entrain some vapour
B. The liquid head in the downcomer should not be greater than one half the plate spacing to
avoid flooding
C. The discharge end of the downcomer must project far enough into the tray liquid so that no
gas bubbles can enter the open end and by pass the bubble caps
D. None of these
In a heat exchanger, shell side fluid velocity can be changed by changing the tube _______________________?
A. Layout
B. Pitch
C. Both A. & B.
D. Neither A. nor B.
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)
Recent Comments