Q.1

Which of the following is a primary fuel ?

  • Blast furnace coke
  • Gasoline
  • Natural gas
  • Wood charcoal
Q.2

Coke compared to the coal from which it has been made, contains

  • less volatile matter.
  • more carbon.
  • greater percentage of ash.
  • all (a), (b) and (c).
Q.3

Pick out the correct statement.

  • Oxygen content decreases from lignite to bituminous coal as the coalification increases.
  • The less the oxygen content, better is the coal, as it reduces the calorific value.
  • With increase in oxygen content, moisture holding capacity of coal increases and the caking power decreases.
  • all (a), (b) and (c)
Q.4

Lurgi coal gasifier is a pressurised __________ bed reactor.

  • moving
  • fixed
  • fluidised
  • entrained
Q.5

In low temperature carbonisation (as compared to high temperature carbonisation) of coal

  • ammonia yield is more.
  • aliphatic tar is produced.
  • free carbon in tar is more.
  • all (a), (b) and (c).
Q.6

High ash containing coke

  • produces more slag when used in the blast furnace.
  • has poor strength and abrasion resistance.
  • is desirable in producer gas manufacture.
  • none of these.
Q.7

Furnace oil consumption in a furnace for a given duty employing preheated combination air (at) may be reduced by about __________ percent as compared to the use of atmospheric combustion air.

  • 5
  • 10
  • 20
  • 35
Q.8

The main reason for making the copper calorimeter (used in bomb calorimeter) silvery white and shining/polished is to

  • minimise its corrosion.
  • avoid radiation heat loss.
  • make it look attractive.
  • none of these.
Q.9

Incomplete combustion of a fuel is characterised by the high __________ in the flue gas.

  • smoke
  • temperature
  • oxygen
  • carbon monoxide
Q.10

Low temperature oxidation of stored coal results in the

  • decrease in its caking power & calorific value.
  • decrease in its carbon & hydrogen content.
  • increase in its oxygen content.
  • all (a), (b) and (a).
Q.11

Which of the following is not a by-product fuel?

  • Sewage gas
  • Refinery gas
  • Producer gas
  • Bagasse
Q.12

White flue gas (resembling steam) coming out of the chimney of a thermal power plant indicates that the fuel used in the boiler furnace is

  • tar
  • coke oven gas
  • pitch
  • pulverised coke
Q.13

With increase in calorific value of fuels, their adiabatic flame temperatures

  • increase
  • decrease
  • remain unchanged
  • may increase or decrease ; depends on the quantity of products of combustion
Q.14

Octane number of4 - trimethyl pen-tane is

  • 0
  • 100
  • in between 0 and 100
  • more than 100
Q.15

Which of the following is not a 'manufactured' fuel ?

  • LPG
  • Coal briquettes
  • Tar
  • Colloidal fuels
Q.16

In low temperature carbonisation of coal as compared to high temperature carbonisation __________ produced is less.

  • difference in gross & net calorific value of the coke oven gas
  • free carbon content in tar
  • yield percentage of coke
  • yield of ammonia present in coke oven gas
Q.17

Combustion of pulverised coal compared to the lumpy coal

  • provides better control of furnace temperature.
  • facilitates combustion with lower excess air.
  • provides higher thermal efficiency & flame temperature.
  • all (a), (b) & (c).
Q.18

A gaseous fuel in order to develop luminousity on burning, must contain

  • carbon monoxide
  • hydrocarbons
  • hydrogen
  • oxygen
Q.19

Which of the following is a single stage, fixed bed high pressure coal gasification process ?

  • Winkler process
  • Kopper-Totzek process
  • Lurgi Process
  • None of these
Q.20

Kopper-Totzek coal gasifier (installed in a coal based nitrogeneous fertiliser plant) employs a/an __________ bed gasifier.

  • entrained
  • moving
  • fixed
  • fluidised
Q.21

Which of the following fertilisers is produced in the by-products recovery (from coke oven gas) plant attached to an integrated steel plant ?

  • Ammonium sulphate
  • Ammonium nitrate
  • Ammonium phosphate
  • None of these
Q.22

Which is the most matured coal ?

  • Lignite
  • Bituminous
  • Semi-anthracite
  • Anthracite
Q.23

The average molecular weight of a flue gas having the composition by volume as CO2 = 25%, O2 = 25%, N2 =will be

  • 27.6
  • 23
  • 47.3
  • 42.9
Q.24

Quantity of coke oven gas produced by high temperature carbonisation of one ton of dry coal may be around __________ Nm3 .

  • 30
  • 300
  • 3000
  • 30, 000
Q.25

Washing of coal does not reduce its

  • S & P content.
  • heating value.
  • fusion point of ash.
  • none of these.
Q.26

Stoichiometric combustion ofkg of carbon requires __________ of oxygen.

  • 1kg mole
  • 22.4 Nm3
  • 32 kg
  • all (a), (b) and (c)
Q.27

The weathering index of a coal

  • gives an idea of the fusion temperature of ash.
  • is related to its calorific value.
  • is a measure of its size stability, when stored & exposed to weather.
  • is a measure of its caking tendency.
Q.28

Gross calorific value will be equal to the net calorific value for

  • H2
  • C2H2
  • CO
  • C2H6
Q.29

Too much of excess air in combustion results in high

  • fuel consumption for the same heat load.
  • stack gas temperature.
  • percentage of oxygen in flue gases.
  • all (a), (b) and (c).
Q.30

Coal tar fuel -(CTFis a mixture of

  • pitch and creosote oil.
  • light oil and pitch.
  • anthracene and crecosote oil.
  • solar oil and pitch.
Q.31

Calorific value of coke even gas produced by low temperature carbonisation of coal is about __________ Kcal/Nm3.

  • 4000
  • 2500
  • 6500
  • 10000
Q.32

Which of the following has the highest flame speed ?

  • CO
  • H2
  • CH4
  • C2H6
Q.33

Use of excess of combustion air in the combustion of fuels results in

  • heat losses.
  • long flame.
  • condensation of water vapour from the fuel gas.
  • none of these.
Q.34

Coal tar (produced by high temperature carbonisation) is the main source of

  • aromatic compounds
  • alphatic compounds
  • paraffins
  • olefins
Q.35

The calorific value is the highest out of the following for

  • producer gas
  • water gas
  • coke oven gas
  • blast furnace gas
Q.36

The ratio of % total carbon obtained in the ultimate analysis of coke and % fixed carbon obtained in the proximate analysis is always

  • 1
  • < 1
  • > 1
  • unpredictable
Q.37

A coal with high __________ content, would ignite most easily.

  • fixed carbon
  • volatile matter
  • ash
  • oxygen
Q.38

Nitrogen present in the flue gas is determined in the orsat apparatus by absorbing it in

  • KOH
  • ammoniacal cuprous chloride
  • pyrogallol solution
  • none of these
Q.39

Use of pulverised coal in boiler furnace provides

  • high calorific value.
  • better combustion.
  • smokeless burning.
  • less erosion on furnace walls.
Q.40

High ash coals

  • are soft & friable (poor strength and size stability).
  • require longer time of carbonisation as ash offers resistance to heat transfer.
  • produce larger quantity of coke oven gas.
  • none of these.
Q.41

In flue gas analysis by Orsat's apparatus, carbon monoxide is absorbed by

  • cuprous chloride
  • potassium hydroxide
  • alkaline pyrogallol solution
  • none of these.
Q.42

Percentage of hydrogen in coke oven gas may be around

  • 10
  • 25
  • 45
  • 60
Q.43

Function of secondary air in pulverised coal firing is to

  • transport the coal to the burner.
  • dry the coal.
  • ensure efficient burning of coal around the burner.
  • reduce primary air requirement.
Q.44

Which of the following is not a manufactured fuel ?

  • Furnace oil
  • Bagasse
  • Semi-coke
  • Kerosene
Q.45

Caking index of coal blend used for blast furnace coke making is about

  • 8
  • 12
  • 22
  • 36
Q.46

Coking coals are invariably

  • lignites
  • bituminous coals
  • semi-anthracites
  • anthracites
Q.47

Which of the following accounts for maximum energy loss in a boiler ?

  • Flue gases.
  • Ash content in the fuel.
  • Incomplete combustion.
  • Unburnt carbon in flue gases.
Q.48

Coke having higher porosity has

  • lower bulk density.
  • lower strength.
  • higher reactivity.
  • all (a), (b) and (c).
Q.49

Coal is pulverised before burning in large capacity boiler furnaces mainly to

  • ensure its complete combustion.
  • facilitate easy ash removal.
  • enhance its calorific value.
  • provide trouble free operation.
Q.50

Bright coal

  • contains more than 90% durain.
  • contains more than 90% fussain.
  • contains mainly vitrain & clarain and is generally coking.
  • is non-coking.
0 h : 0 m : 1 s