adkasdas Flashcards
Which of the following material is seldom used
for pressure vessel construction?
Rimmed Steel
25 per cent cut segmental baffle means that
the baffle
Height is 75% of the ID of the
shell
Liquid/petroleum fuel storage tanks are built
underground (as in case of petrol pumps),
when the storage capacity is less than
__________ kilolitres.
45
Le/D for fully open globe value may be around
300
Holes of a sieve tray are arranged in triangular
pitch of __________ times the hole diameter.
2.5 to 5
In case of a shell and tube heat exchanger,
the minimum shell thickness for carbon steel
(inclusive of corrosion allowance) depends on
shell diameter and is in the range of
__________ mm.
5-11
In case of bubble cap distillation column of
diameter greater than 1.2 meters, the cap
diameter is roughly about __________ cm.
10
Tube side pressure drop in a 1-2 heat
exchanger (for turbulent flow of fluids through
the tubes) is about __________ times, that in
a 1-1 heat exchanger having the same size &
number of tubes and operated at the same
liquid flow rate.
8
In a heat exchanger, shell side fluid velocity
can be changed by changing the tube
layout and pitch
It is not desirable to design a heat exchanger
for LMTD correction factor, FT, of less than
0.8
Triangular pitch tube layout as compared to
square pitch in a shell and tube heat
exchanger
permits the use of more tubes
in a given shell diameter
Bracket supports are the most suitable for
supporting __________ vessels.
thick walled vertical
Two iron pipes of the same nominal diameter
but different schedule numbers will have the
same
outside diameter
Lessing ring is formed by the addition of a
partition across the centre of a raschig ring,
which results in an area increase of about
__________ percent.
20
Shell side heat transfer co-efficient in case of
square pitch as compared to the triangular
pitch under similar condition of fluid flow and
tube size is
less
_ tray arrangement is recommended for
distillation column having diameter up to 4 ft.
Cross flow
The main purpose of providing stepping on the
trays is to
facilitate handling of large flow
rate of liquid
Needle valves are generally not used for
very large diameter pipes
Which of the following is an undesirable
dynamic characteristic of an instrument ?
time lag
Response of a system to a sinusoidal input is
called __________ response
frequency
Mass transfer rate between two fluid phases
does not necessarily depend on the
__________ of the two phases.
chemical properties
Which of the following is the most suitable for
extraction in a system having very low density
difference
centrifugal extractor
Total reflux in a distillation operation requires
minimum
A. reboiler load C. condenser load
B. number of plates D. all (a), (b) and (c)
B. number of plates
Fenske’s equation for determining the minimum
number of theoretical stages in distillation column
holds good, when the
A. relative volatility is reasonably constant.
B. mixture (to be separated) shows negative deviation
from ideality.
C. mixture (to be separated) shows positive deviation
from ideality.
D. multicomponent distillation is involved.
A. relative volatility is reasonably constant.
When the temperature and humidity of air is
low, we usually use __________ draft cooling
tower.
natural
Which of the following is used to set the diameter
of the distillation column ?
A. Number of theoretical plates.
B. Static submergence.
C. Allowable vapor velocity.
D. Length of straight rectangular weir on cross-
flow tray.
C. Allowable vapor velocity.
Saddle supports are used for supporting
__________ vessels.
Horizontal Cylindrical
Solvent extracted oil
A. has low free fatty acid content.
B. is odorless.
C. has more of unsaturates.
D. none of these.
D. none of these.
Which of the following is not required in the
manufacture of soda ash by Solvay process ?
A. Ammonia C. Limestone
B. Nitric acid D. None of these
B. Nitric acid
Kaoline is a/an
refractory material
Phenol is mainly used
to produce phenol
formaldehyde
Main constituent of dolomite is
MgCO3
Conversion of CO to CO2 by steam in
presence of a catalyst is called
shift conversion
Bleaching action of bleaching powder is due to
its __________ properties.
oxidizing
Portland cement consists mainly of
CaO and SiO2
__________ glass has the lowest coefficient
of thermal expansion and hence is more heat
resistant.
Pyrex
Mannheim furnace is used in the manufacture
of
hydrochloric acid
Thermosetting materials
are cross-linked molecules.
__________ iron is the purest form of iron.
Wrought
Enamels
give good glossy finish.
Black liquor is converted into white liquor by
A. evaporation and burning the concentrate
followed by causticisation of products.
B. multi-effect evaporation only.
C. selective liquid extraction.
D. extractive distillation.
A. evaporation and burning the concentrate
followed by causticisation of products.
Varnish does not contain
pigment
Which of the following same diameter columns
gives lowest pressure drop per unit height
Packed Column
Neoprene is chemically known as
Polychlorepene
Molecular weights of polymers are in the
range of
10^2
to 10^7
In distillation columns, the number of bubble
caps per tray primarily depends upon the
allowable gas and liquid
velocities.
Vertical vessels are not supported by
saddles
Pick out the wrong statement about the design of a sieve plate column.
A. An increased weir height improves the tray efficiency at the cost of high plate
pressure drop; optimum wear height being 40-90 mm for column pressure above
atmospheric and 6-12 mm for vacuum columns.
B. For segmental downcomers, the chord length is 60-80% of the column
diameter. An initial value of downcomer area of 12% is taken in the design.
C. Width of the calming section provided at the inlet and outlet sides of the plate is
75 mm for column diameter below 1.5 meters and 100 mm for larger diameter
columns.
D. Minimum recommended downcomer residence time for the disengagement of
entrained vapor is the same for both foaming and non-foaming liquids, which is
about 20 seconds.
D. Minimum recommended downcomer residence time for the disengagement of
entrained vapor is the same for both foaming and non-foaming liquids, which is
about 20 seconds.
Rivets are generally specified by the
shank diameter
Oleum produces fumes of
SO3
20% oleum means that in 100 kg oleum, there
are 20 kg of
A. SO3 and 80 kg of H2SO4
.
B. H2SO4 and 80 kg of SO3
.
C. SO3
for each 100 kg of H2SO4
.
A. none of these.
A. SO3 and 80 kg of H2SO4
Inversion of sucrose produces
glucose
Linde process of gas liquefaction employs
adiabatic expansion through a
throttle valve (Joule-Thomson expansion)
The major use of butadiene is
in the manufacture of
synthetic rubber.
Hydrogenation of oil takes place in a/an
__________ reactor.
trickle bed reactor
__________ glass is used for the
manufacture of optical glass.
flint
Favorable conditions for the liquefaction of
gases in general are
high pressure & low
temperature.
Which of the following is an yellow pigment ?
A. Titanium dioxide C. Ferrous sulphate
B. Lead chromates D. Zinc sulfides
C. Ferrous sulphate
Common salt is generally not produced
commonly by __________ method from
brine.
freeze drying
Sulphuric acid is mainly used in the
__________ industry.
fertilizer
Main use of hydrazine is
rocket fuel
Main use of liquid nitrogen is in
refrigerative cooling.
Raw materials required for the manufacture of
__________ is acetylene and hydrochloric
acid.
vinyl chloride
Yellow glycerine is made into white, using
activated carbon
Gypsum is chemically
calcium sulfate
Zeigler process
produces high density
polyethylene.
Pick out the one which is a first order instrument.
A. Mercury in glass thermometer (without any
covering or air gap).
B. Bare metallic thermometer.
C. Bare vapor pressure thermometer.
D. All (a), (b) and (c).
D. All (a), (b) and (c).
Pick out the wrong statement.
A. O2
, NO and NO2 exhibit paramagnetic properties as a
result of unpaired electrons.
B. CO2
is the strongest paramagnetic gas.
C. Paramagnetic susceptibility of gases decreases with
temperature.
D. Paramagnetic susceptibility of gases permits the
measurement of their concentration.
B. CO2
is the strongest
paramagnetic gas.
A negative gain margin expressed in
decibels means a/an __________
system.
unstable
Thermistor, which has high temperature
coefficient of resistivity, is used as the
sensing element in resistance
thermometer. It is a/an
solid semi-conductor
Flapper nozzle is used in a/an
__________ controller.
pneumatic
Working principle of radiation
pyrometer is based on the
Stefan-Boltzman law
Which of the following relates the emf.
generated in a single homogeneous wire
to the temperature difference ?
Thomson effect
Bubble cap tray is the most
commonly used tray in large
distillation column, because
of its flexibility and nearly
constant efficiency under varying
conditions of operation.
Apex angle of conical heads
used in the bottom heads of
chemical process equipment
is usually
60Deg
Nominal size of a pipe is an indication
of its __________ diameter.
approximate
In shell and tube heat exchangers,
straight tie rods are used to
hold baffle in space.
The ratio of pressure forces to inertial
forces is called the __________ number.
Euler
The ratio of inertial forces to elastic
forces is called the __________ number.
Mach
When the momentum of one fluid
is used for moving another fluid,
such a device is called a/an
jet pump
The normal stress is the same
in all directions at a point in a
fluid, when the fluid is
having no motion of one fluid
layer relative to the other.
Most commonly used joint in
the underground pipe lines
is the
sleevejoint
Water hammer in a pipeline
results from the
rapid pressure change due to
a rapid change in the rate of flow.
Maxwell’s thermodynamic relations
applies to the
chemical systems in
equilibrium.
Which of the following is not an explosive ?
A. TNT
B. CMC
C. RDX
D. Lead azide
B. CMC
Foot valves provided in pumps
are __________ valves.
directional control
The most suitable material of
construction for a sewer to carry
sewage under high pressure is
steel
__________ addition increases
the depth of hardness of steel.
chromium
