Q.1

For storing hazardous chemicals in large storage tanks, the minimum safe distance between the two tanks should range between __________ times the tank diameter.

  • 1 to 1.5
  • 2.5 to 3.5
  • 4 to 5
  • 6 to 8
Q.2

1.2 to 3.8 cms is the value of the

  • downcomer liquid seal in case of a balanced tray design.
  • static submergence in case of a bubble cap tray for column operating under pressure (≥ 1 atm.).
  • skirt clearance for bubble caps.
  • all (a), (b) and (c).
Q.3

A binary liquid azeotropic mixture has boiling point higher than either of the components, when it shows __________ deviation from Raoult's Law.

  • positive
  • negative
  • no
  • none of these
Q.4

High pressure fluid in a shell and tube heat exchanger should preferably be routed through the

  • tubes to avoid the expansion of high pressure shell construction.
  • shell side for smaller total pressure drop.
  • shell side, if the flow is counter-current and tube side if the flow is co-current.
  • shell side for large overall heat transfer co-efficient.
Q.5

The retention time of material in a rotary dryer depends upon its

  • rpm
  • slope & length
  • flights arrangement
  • all (a), (b) and (c)
Q.6

In a multiple effect evaporator system having 'n' effects, the amount of water evaporated per unit surface area in approximately equal to __________ times that in a single effect.

  • 'n'th
  • (1/n)th
  • 0.5 nth
  • 1.5 nth
Q.7

In a shell and tube heat exchanger, the clearance of the tube is generally

  • not less than one-fourth of the tube diameter or 3/16".
  • more than the tube diameter.
  • equal to the tube diameter.
  • more in case of triangular pitch as compared to the square pitch tube layout.
Q.8

Hole diameter of the seive trays in the distillation column ranges from __________ mm.

  • lto3
  • 4 to 8
  • 3 to 12.5
  • 12.5 to 18.5
Q.9

Pick out the correct statement.

  • It is preferred to use a vertical condenser for condensation of vapor from a distillation column without sub-cooling
  • Draining of residual liquid on tray during shut down of distillation column is facilitated by weep holes.
  • Random packing a packed tower offers the advantage of lower pressure drop and higher throughput of fluids as compared to regular/stacked packing.
  • Risers are generally not connected to the plate in a distillation coloumn by bolts, rivets or welding.
Q.10

An increase in the liquid resistance to interphase mass transfer and a resultant reduction in plate efficiency is caused by

  • an increase in liquid viscosity.
  • an increase in relatived volatility for rectification columns.
  • decrease in gas solubility for absorbers.
  • all (a), (b) and (c).
Q.11

A perforated plate has holes of diameter dn arranged in a pitch ph. Each hole has a tube of I.D. dt passing through it. The ligament efficiency is given by

  • (ph - dh)/ph
  • (ph - dh . dt/2)/ph
  • (ph - dt)/ph
  • (ph - dh)/dh
Q.12

Steam is preferred to be used as a heating medium in heat exchangers, because of its

  • low cost.
  • high latent heat.
  • non-corrosive condensate.
  • high film co-efficient.
Q.13

The minimum shell thickness for tank ≤metres diameter is limited to __________ mm, for reasons of elastic stability.

  • 2
  • 5
  • 10
  • 15
Q.14

Angled baffles are preferred in the agitation tank to control the swirling action; if the viscosity of the liquid to be mixed is aboutpoise. However, the baffle may be completely eliminated for mixing liquids having viscoisty above __________ poise.

  • 300
  • 600
  • 1000
  • 1500
Q.15

Which of the following factors determine the amount of entrainment in a distillation column ?

  • Plate spacing.
  • Depth of liquid above the bubble cap slots.
  • Vapour velocity in the volume between the plates.
  • All (a), (b) and (c).
Q.16

The testing pressure of storage tanks and pressure vessels designed as per Indian standard codes should be about __________ times.the design pressure.

  • 1.5 to 2
  • 3 to 4
  • 4 to 5
  • >5
Q.17

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.
  • it incurs less pressure drop as compared to any other try designed for the same duty.
  • it eliminates the foaming and entrain-ment tendency during operation.
  • none of these.
Q.18

In actual operation of a bubble cap distillation tower, the __________ at the bottom of the tower is more than that at the top of the tower.

  • molal flow rate of vapour
  • vapour molecular weight
  • pressure and temperature
  • all (a), (b) and (c)
Q.19

Pick out the wrong statement

  • In a flanged and standard dished head, the crown radius is ≤ shell outside diameter.
  • In a flanged and shallow dished head, the crown radius is > shell outside diameter.
  • Flat head covers are most suitable for larger vessels operating at very high pressure.
  • Flanged only head is a type of flat head in which gradual change in the shape at the centre results in reduced local stresses.
Q.20

Diameter of the seive tray column is determined by the

  • lower limit of vapour velocity.
  • upper limit of the vapour velocity.
  • hole diameter of the seive tray.
  • height of the plate spacing.
Q.21

Factor of safety (i.e., overdesign factor) in heat transfer equipments is about __________ percent more than the actual/theoretical design factor.

  • 5-10
  • 15-20
  • 30-35
  • 35-40
Q.22

"A claming section" before the liquid flows into the downcomer is privided to

  • permit release of entrained vapour in the liquid.
  • reduce the discharge fluctuation.
  • ensure better vapour-liquid contact.
  • cool the liquid before it flows down.
Q.23

In the design of a bag filter, the gas temperature is an important consideration, as it affects the

  • gas density
  • gas viscosity
  • fibre selection
  • all (a), (b) & (c)
Q.24

__________ is the determining factor for the number of bubble caps to be used per tray.

  • Permissible slot velocity
  • Tray diameter
  • Liquid load
  • Vapor load
Q.25

Hazards associated with the relief valve leakage for extremely hazardous material storage can be taken care of by providing

  • rupture diaphragm
  • dikes
  • surge chamber
  • none of these
Q.26

__________ shapedroof is the most commonly used roof for cylinderical storage tanks.

  • Conical
  • Flat
  • Dome
  • Umbrella
Q.27

A pressure vessel is said to be made of 'thick' shell, if the ratio of its diameter to wall thickness is

  • 10
  • 10
  • 20
  • 20
Q.28

If 'D' is the inside diameter of the shell of a shell and tube heat exchanger, then the baffle spacing is usually in the range of

  • D/2 or minimum 2" to 5D.
  • D/5 or minimum 2" to 5D.
  • D/5 or minimum 2" to D.
  • none of these.
Q.29

In case of design of a shell and tube heat exchanger,

  • minimum cleaning lane of 6.5 mm is provided, when tubes are on a square pitch.
  • minimum tube sheet thickness (in which tubes are fixed) is equal to the O.D. of the tube upto 15 mm tube diameter; and for > 15 mm tube diameter, tube sheet thickness is smaller than tube diameter.
  • O.D. of the tube is 6 to 40 mm while the tube lengths used are 0.5, 2.5, 3.0, 4.0, 5.0, 6 metres.
  • all (a), (b) & (c).
Q.30

Ratio of tube length to shell diameter for a shell and tube heat exchanger is

  • 8 : 1 to 12 : 1 for both liquid-liquid and gas-gas heat exchangers.
  • 4 : 1 to 8 : 1 for liquid-liquid exchanger.
  • < 4 : 1 for gas-gas exchangers.
  • both(b) & (c).
Q.31

The absorption factor is defined as (where, S1 = slope of the equilibrium curve, S2 = slope of the operating line)

  • S1/S2
  • S1.S2
  • S2/S1
  • 1/S1.S2
Q.32

Rotary driers are most economically designed for the number of heat transfer units (HTU) from

  • 0.01 to 1
  • 1.5 to 2.5
  • 5 to 10
  • 10 to 20
Q.33

The units of Young's modulus of elasticity and __________ are the same.

  • strain
  • stress
  • modular ratio
  • none of these
Q.34

With increase in temperature drop (in a shell and tube heat exchanger), the LMTD correction factor, FT

  • decreases very rapidly
  • increases very rapidly
  • remains constant
  • increases linearly
Q.35

In common bubble cap distillation column design practice, riser area is approximately equal to (where, Aa = Annular passage area, and Sa = Slot area)

  • Aa = Sa
  • 1.2 Aa = 1.2 Sa
  • Sa = 1.5 Aa
  • Aa = 1.5 Sa
Q.36

Pick out the wrong statement about distillation operation

  • Distillation under vacuum is a substitute for steam distillation.
  • In differential (simple) distillation, the vapour is removed as soon as it is formed without appreciable condensation.
  • In flash (equilibrium) distillation, a definite fraction of liquid is vaporised in such a way that the evolved vapour & residual liquids are in equilibrium with each other.
  • Flash distillation, differential distillation & steam distillation are all continuous distillation processes.
Q.37

Minimum baffle spacing recommended in a shell and tube heat exchanger is equal to

  • 5 cms
  • 40% of the I.D. of the shell
  • 25 cms
  • I.D. of the shell
Q.38

What is the slope of the operating line in the stripping section of a distillation column ?

  • 0
  • ∞
  • > 1
  • < 1
Q.39

Pick out the wrong statement pertaining to 'Horton sphere' used for the storage of liquid ammonia.

  • Diameter of Horton sphere is normally 6 to 25 metres and it is supported by 6 to 12 nos. tubular or rolled section column.
  • Thickness of spherical shell is half that of the cylinderical vessel under same operating pressure condition. Besides, the ratio of surface area to volume is less for sphere than any other shape ; hence insulation required is less.
  • Horton sphere is used for the storage of gases and volatile liquid at a moderate pressure of 1 to 10 kg/cm2 .
  • Horton sphere is used for the storage of liquid at sub-zero temperature at very high pressure upto 200 kg/cm2 .
Q.40

Rate of filtrate delivery is inversely proportional to the

  • filtering area & the pressure difference driving force.
  • viscosity of filtrate.
  • cake & filter medium resistance.
  • both (a) and (b)
Q.41

Brass valves are usually made for pipe sizes __________ inches.

  • ≤1
  • ≤2
  • >2.5
  • >3.5
Q.42

In a cylinderical vessel subjected to internal pressure, the longitudinal stress σL and the circumferential stress, σn are related by

  • σh = 2 σL
  • σh = σL
  • σh = σL/2
  • no relation exists
Q.43

The dust collection efficiency of a cyclone separator

  • decreases with increase in gas flow rate.
  • is inversely proportional to the mass of the dust particle.
  • is directly proportional to the radius of the dust particle path.
  • none of these.
Q.44

In shell and tube heat exchangers, straight tie rods are used to

  • hold baffle in space.
  • fix the tubes in position.
  • account for thermal strain.
  • none of these.
Q.45

The ratio of down take area to cross-sectional area of the tube, for calendria type evaporator ranges from

  • 0.5 to 1
  • 1 to 1.5
  • 1.5 to 2
  • 2 to 2.5
Q.46

The difficulty of liquid distribution in packed towers is accentuated, when the ratio of tower diameter to packing diameter is

  • < 30
  • < 7
  • > 7 < 15
  • > 20 < 50
Q.47

In the design of a shell and tube heat exchanger, the corrosion allowance

  • need not be provided for non-pressure parts like tie rods, spacers, baffles, supports etc.
  • for carbon steel and cast iron pressure parts is 1.5 mm (except for tubes) and for severe conditions it is 3 mm.
  • for internal cover and tube sheet is provided on both the sides.
  • all (a), (b) & (c).
Q.48

The normal range of velocity of steam in pipes is __________ m/sec.

  • 0.1-0.5
  • 1-5
  • 10-20
  • 80-100
Q.49

For annular flow of a fluid, the ratio of the equivalent diameter for pressure drop calculation to the equivalent diameter for heat transfer calculation is

Q.50

Heat transfer co-efficient, hG(Kcal/hr.m2 .°C) and mass velocity of air, G (kg/hr.m2 ) for air flow parallel to the surface in case of constant drying rate in batch drying is related as hG = 0.0176G0.8. But when the flow of air perpendicular to the surface is encountered, this equation changes to

  • hG = 1.004G0.37
  • 1.004G0.8
  • hG = 0.0176G0.37
  • 0.0176G1.37
0 h : 0 m : 1 s