What is the slope of the feed line, if the feed to a distillation column is a saturated liquid ?
-
0 -
∞ -
> 1 -
< 1
In which of the following evaporators, steam is fed inside the tube while the liquor is outside the tube ?
-
Long tube vertical evaporator -
Short tube vertical evaporator -
Horizontal tube evaporator -
None of these
Pick out the correct statement
-
Centre to centre distance between two consecutives rivets in a row is called the pitch. -
A rivetted joint made in overlapping plates is called butt joint. -
Hole size drilled in rivetted plates is less than the actual size of the rivet. -
none of these.
Pick out the wrong statement.
-
In practical operation, distillation towers having diameter 3-6 metres equipped with bubble cap (round) size of 15 cms are used. -
Height of packing in a packed tower is about 3 times the column diameter for raschig rings and about 5 to 10 times the column diameter for saddle packing. -
In a seive tray, the minimum hole diameter is equal to the tray thickness. -
In a stainless steel seive tray, the minimum hole diameter is equal to 10 times the plate thickness.
__________ head is the most economical for cylindrical vessels designed for operating at high pressure (>atm.).
-
Hemispherical -
Dished -
Ellipsoidal -
Conical
Overall mass transfer co-efficient in case of absorption of __________ in water is based on the gas film co-efficient only, as the mass transfer process is gas film (phase) controlling.
-
CO2 -
SO2 -
NH3 -
none of these
Power required for agitation depends upon the
-
height & properties of the liquid. -
agitator type & speed of agitation. -
size of agitator & the tank. -
all (a), (b) and (c).
Welded joint efficiency in the design of chemical process equipment is taken as
-
0.55 -
0.75 -
0.85 -
0.95
Vertical storage vessels are never supported by __________ support.
-
bracket -
saddle -
skirt -
lug
Filtration rate is affected by the
-
pressure drop across the cake & filter medium. -
cake & filter medium resistance. -
area of filtering surface & the viscosity of filtrate. -
all (a), (b) and (c).
A single pass air heater is connected to a two pass unit. For the air flow rate and other conditions remaining the same, the film heat transfer co-efficient for air will vary in the ratio of
-
2 -
20.8 -
20.2 -
none of these
Safety valves are provided in chemical equipments to guard against excessive
-
temperature -
pressure/pressure fluctuation -
turbulence -
noise
In the downcomer of a distillation column, the minimum recommended residence time is about __________ seconds.
-
2.5 -
5 -
12.5 -
17.5
Tube height in a calendria type evaporator is normally less than __________ metres.
-
1 -
2 -
3.5 -
5.5
In a double pipe (concentric) heat exchanger, the hydraulic radius for heat transfer (for a fluid flowing through the annulus) would be
-
same as that for fluid flow. -
less than that for fluid flow. -
more than that for fluid flow. -
D2 - D1 (D1 and D2 are I.D. of inner and outer pipes respectively).
Liquid gradient over a tray can be minimised by
-
providing a higher skirt clearance or a higher weir. -
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. -
using split flow, radial flow or cascade flow for column diameter large than 4 ft. -
all (a), (b) and (c).
Pick out the wrong statement.
-
Lug supports are less expensive than other type of supports. -
A pipe is differentiated from a tube by the fact that a pipe has a greater wall thickness compared to the tube. -
A reducer is used to change the direction of a pipe in a straight run. -
The method of fixing tubes to a tube sheet by expanding is called 'tube rolling'.
Elastic failure of a material occurs, when the tensile stress equals yield strength, yield point or the elastic limit. Also, the elastic failure occurs according to maximum strain theory, when the maximum tensile strain equals (where, σ = yield strength and E = modulus of elasticity)
-
E -
σ -
σ/E -
E/σ
In a shell and tube heat exchanger for a given heat transfer surface area, smaller diameter tubes are favoured as compared to larger diameter ones ; because the smaller diameter tubes
-
are easier to clean. -
are less prone to fouling. -
can be fitted into a smaller shell diameter hence the cost of the heat exchanger would be less. -
none of these.
For amm hole drilled in plates to be rivetted, the shank diameter of the rivet should be __________ mm.
-
25 -
23 -
26 -
27
Pick out the wrong statement.
-
An air cooled finned pipe is diagram-matically represented by 
-
A heat exchanger is diagrammatically represented by 
-
A 90° welded elbow is diagrammatically represented by 
-
A pipe still heater is diagrammatically represented by 
Friction factor for turbulent flow in a new pipe is given by
-
-
-
f = 0.22 NRe0.5 
-
Pick out the wrong statement.
-
An air cooled finned pipe is diagram-matically represented by -
A heat exchanger is diagrammatically represented by -
A 90° welded elbow is diagrammatically represented by -
A pipe still heater is diagrammatically represented by
In a shell and tube heat exchanger having square pitch, the shell side equivalent diameter is given by (where, P = pitch, d = outside diameter of the tube)
-
-
-
-
πd/4P2