3954. Movement of pipeline caused by thermal expansion is taken care by providing
expansion joint.
changes in its direction.
change in the shape of pipeline.
all (a), (b) and (c).
✅ The correct answer is option D.
3955. Back-trapping in a distillation column results due to
low gas velocity.
high gas velocity.
excessive liquid gradient over the tray.
low reflux ratio.
✅ The correct answer is option C.
3960. Thin spherical shells subjected to internal pressure, develop __________ stresses.
radial
circumferential
both (a) & (b)
neither (a) nor (b)
✅ The correct answer is option A.
3966. In most of the shell and tube heat exchangers, the tube pitch is generally __________ the tube diameter.
less than
1.25-1.50 times
2.5 times
one-fourth of
✅ The correct answer is option B.
3971. The diameter of a propeller agitator used in agitation tank ranges from __________ percent of the tank diameter and its peripherial speed is normally 300 to 500 metres/minute.
5 to 10
15 to 30
40 to 50
55 to 75
✅ The correct answer is option B.
3976. Weep holes provided in the plates of a distillation column
facilitate draining out liquid from a tray when the unit is not in operation.
are normally located near the overflow weir so that any delivery of liquid during operation follows approximately the same path as the overflow fluid.
must be large enough (usually 1/4″ to 5/8″ dia) to prevent plugging but should not deliver excessive amount of fluid during operation.
all (a), (b) and (c).
✅ The correct answer is option D.
3917. Catalyst used in steam reforming of naphtha is
Bauxite
Cobalt
Nickel oxide on alumina support
Chromium
✅ The correct answer is option C.
3919. In an ammonia plant, the purge off is essential to
Maintain inert gas concentration within a limit
Remove excess poisonous gases
Maintain H₂ : N₂ ratio at 3 :1
Remove uncondensed ammonia vapour
✅ The correct answer is option C.
3924. Dehydration of ammonium carbamate to yield urea is a/an __________ reaction.
Exothermic
Endothermic
Autocatalytic
Catalytic
✅ The correct answer is option B.
3929. Which is a catalyst promoter used in catalytic ammonia synthesis reaction?
Al₂O₃
Cr₂O₃
K₂O
MnO
✅ The correct answer is option C.