Fuels And Combustion MCQs

Option A: Aromatic compounds

Option B: Aliphatic compounds

Option C: Paraffins

Option D: Olefins

Correct Answer: Aromatic compounds ✔

Option A: Tar

Option B: Sulphide Coke

Option C: Coke Oven Gas

Option D: Pulverised coke

Correct Answer: Coke Oven Gas ✔

Option A: LPG is also used as fuel for automobiles & small furnaces and for cutting & welding of

Option B: The minimum temperature, at which a petroleum oil vapor catches fire and continues to burn,

Option C: Each ton of petroleum oil on distillation produces about 30-50 Nm3 of gas

Option D: Maximum yield of naphthalene is obtained on distillation of crude oil

Correct Answer: B. The minimum temperature, at which a petroleum oil vapor catches fire and continues to burn,
is called its flash point ✔

Option A: High concentration of oxygen in flue gas means high stack loss

Option B: Gaseous fuels require the least % excess air for complete combustion

Option C: The ratio of fixed carbon to volatile matter percentage in coal is called its ‘fuel ratio’

Option D: Calorific value of natural gas is more than that of LPG

Correct Answer: Calorific value of natural gas is more than that of LPG ✔

Option A: Briquettes

Option B: Wood

Option C: Oil gas

Option D: Pitch creosote mixture

Correct Answer: Wood ✔

Option A: 10

Option B: 25

Option C: 50

Option D: 80

Correct Answer: 50 ✔

Option A: Blast furnace gas

Option B: Coke oven gas

Option C: Sewage gas

Option D: Natural gas

Correct Answer: Blast furnace gas ✔

Option A: Maximum to minimum heat input ratio

Option B: Maximum to minimum permissible gas flow rate

Option C: Both A. & B.

Option D: Minimum to maximum heat input ratio

Correct Answer: C. Both A. & B. ✔

Option A: Gobar gas

Option B: Refinery gas

Option C: Converter gas

Option D: Blast furnace gas

Correct Answer: Blast furnace gas ✔

Option A: More than

Option B: Less than

Option C: Equal to

Option D: Either more or less; depends on the type of fuel

Correct Answer: More than ✔

Option A: MgO & Na2CO3

Option B: MgSO4 & BaCl2

Option C: BaSO4 & NaCl

Option D: MgCO3 & NaCl

Correct Answer: MgO & Na2CO3 ✔

Option A: Decreases the hardness of coke

Option B: Decreases the abrasion resistance of coke

Option C: Causes brittleness in steel

Option D: None of these

Correct Answer: None of these ✔

Option A: 500

Option B: 750

Option C: 950

Option D: 1100

Correct Answer: 750 ✔

Option A: Facilitates by-products recovery

Option B: Takes 2-3 days for coking of coal but requires no external fuel for heating

Option C: Gives larger yield of coke (around 85%) as compared to by-product ovens

Option D: Produces coke with very poor strength

Correct Answer: Takes 2-3 days for coking of coal but requires no external fuel for heating ✔

Option A: If its ash content is zero

Option B: If its carbon content is very low

Option C: If its hydrogen/hydrogen compound content is zero

Option D: Under no circumstances

Correct Answer: If its hydrogen/hydrogen compound content is zero ✔

Option A: Hydrogenation

Option B: Gasification

Option C: Carbonisation

Option D: None of these

Correct Answer: Hydrogenation ✔

Option A: Is friable, charcoal like substance

Option B: Has highest fixed carbon and lowest volatile matter content of all the four banded components

Option C: Is non-coking, but when blended with highly coking coal, controls its swelling and produces

Option D: All A., B. and C.

Correct Answer: D. All A., B. and C. ✔

A. 71%
C. In between 37 & 71%
D. None of these

Correct Answer: 71% ✔

Option A: 30

Option B: 50

Option C: 75

Option D: 95

Correct Answer: 75 ✔

Option A: Carbon tetrachloride

Option B: Sand (40%)

Option C: Mineral oil of high viscosity & specific gravity (1.6)

Option D: None of these

Correct Answer: Sand (40%) ✔

Option A: Moisture

Option B: Ash

Option C: Volatiles

Option D: Carbon

Correct Answer: Carbon ✔

Option A: Exothermic

Option B: Endothermic

Option C: Autocatalytic

Option D: None of these

Correct Answer: Exothermic ✔

Option A: Gravimetric analysis of flue gas

Option B: Finding out combustion efficiency

Option C: Direct determination of nitrogen in flue gas by absorbing it in ammoniacal cuprous chloride

Option D: None of these

Correct Answer: None of these ✔

Option A: 60

Option B: 160

Option C: 500

Option D: 750

Correct Answer: 60 ✔

Option A: CO

Option B: CH4

Option C: CO2

Option D: S

Correct Answer: CO ✔

Option A: 8800 kcal/m3

Option B: 8800 kcal/kg

Option C: Same as that of coal middling

Option D: 25000 kcal/kg

Correct Answer: 8800 kcal/kg ✔

Option A: The hydrocarbons crack thereby choking and fouling the heat transfer surface by carbon soot

Option B: It reduces its calorific value tremendously

Option C: It reduces its flame temperature tremendously

Option D: There are chances of explosion during preheating

Correct Answer: The hydrocarbons crack thereby choking and fouling the heat transfer surface by carbon soot ✔

Option A: Bomb

Option B: Boy’s

Option C: Junkers

Option D: None of these

Correct Answer: Bomb ✔

Option A: 500

Option B: 1500

Option C: 6500

Option D: 20000

Correct Answer: 500 ✔

Option A: Controlling the excess air

Option B: Oxygen enrichment of combustion air

Option C: Using low c.v. fuels

Option D: Maintaining proper draft in the furnace

Correct Answer: Controlling the excess air ✔

Option A: Back draughting

Option B: Banking

Option C: Under pressurising

Option D: None of these

Correct Answer: Banking ✔

Option A: Contains more volatile matter than bituminous coal

Option B: Ignites more easily than bituminous coal

Option C: Is essentially a coking coal

Option D: Burns with short, bluish, yellow-tipped flame producing very little smoke

Correct Answer: Burns with short, bluish, yellow-tipped flame producing very little smoke ✔

Option A: Fully

Option B: Partially

Option C: Not at all

Option D: Negligibly

Correct Answer: Not at all ✔

Option A: Bright

Option B: Splint

Option C: Non-banded

Option D: Boghead

Correct Answer: Splint ✔

Option A: Pneumatically convey the pulverised coal

Option B: Completely burn the volatile matter

Option C: Burn the lumpy coal

Option D: None of these

Correct Answer: Completely burn the volatile matter ✔

Option A: 30

Option B: 65

Option C: 120

Option D: 180

Correct Answer: 65 ✔

Option A: Partial combustion of coal

Option B: Partial combustion of large size (< 50 mm) coke

Option C: High pressure gasification of coal (e.g. in Lurgi gasifier)

Option D: Atmospheric pressure gasification of coal (e.g., in Kopper-Totzek gasifier)

Correct Answer: Partial combustion of large size (< 50 mm) coke ✔

Option A: CO content

Option B: Dew point

Option C: CO2 content

Option D: O2 content

Correct Answer: CO content ✔

Option A: Benzol

Option B: Toluene

Option C: Pyridine

Option D: Cerosote

Correct Answer: Toluene ✔

Option A: Height of the coal heap should be < 3 metres

Option B: Maximum 200 tons should be stored in a heap

Option C: Both A. and B.

Option D: Neither A. nor B.

Correct Answer: C. Both A. and B. ✔

Option A: Forced draft fan

Option B: Induced draft fan

Option C: Steam ejector

Option D: Natural draft

Correct Answer: Natural draft ✔

Option A: M = 1.8 A

Option B: M = 0.5 A

Option C: M = 1.1 A

Option D: M = A

Correct Answer: M = 1.1 A ✔

Option A: 5

Option B: 50

Option C: 500

Option D: 5000

Correct Answer: 5 ✔

Option A: Develops a non-luminous flame

Option B: Develops a low temperature flame

Option C: Can be done with less excess air

Option D: Provides a lower rate of heat release

Correct Answer: Can be done with less excess air ✔

Option A: Density

Option B: Porosity

Option C: Electrical resistivity

Option D: None of these

Correct Answer: Density ✔

Option A: Pitch and creosote oil

Option B: Light oil and pitch

Option C: Anthracene and crecosote oil

Option D: Solar oil and pitch

Correct Answer: Pitch and creosote oil ✔

Option A: Prevention of clinker formation in the oven

Option B: Controlling the dust nuisance while charging the coal

Option C: Reducing the cracking of hydrocarbons in the gas and increasing the percentage of CO &

Option D: All A., B. and C.

Correct Answer: D. All A., B. and C. ✔

Option A: CO2, O2, CO

Option B: CO, O2, CO2

Option C: CO2, CO, O2

Option D: O2, CO2, CO

Correct Answer: CO2, O2, CO ✔

Option A: Caking index

Option B: Yield of carbonised products

Option C: Friability & oxygen content

Option D: Calorific value

Correct Answer: Friability & oxygen content ✔

Option A: Reactivity

Option B: Hardness

Option C: Strength

Option D: None of these

Correct Answer: Reactivity ✔

Option A: Burns completely

Option B: Gives smokeless burning

Option C: Shows little or no fusing action

Option D: None of these

Correct Answer: Shows little or no fusing action ✔

Option A: Carbon, hydrogen, nitrogen & sulphur

Option B: Carbon, ash, sulphur & nitrogen

Option C: Carbon, sulphur, volatile matter & ash

Option D: Carbon, volatile matter, ash & moisture

Correct Answer: Carbon, hydrogen, nitrogen & sulphur ✔

Option A: Proper fuel preparation

Option B: Keeping the flue gas exhaust temperature very high

Option C: Adopting efficient-fuel firing technique & equipment

Option D: Supplying correct quantity of combustion air

Correct Answer: Keeping the flue gas exhaust temperature very high ✔

Option A: Incomplete combustion

Option B: Dry gas/stack gas loss

Option C: Moisture loss

Option D: None of these

Correct Answer: Dry gas/stack gas loss ✔

Option A: Incomplete combustion

Option B: Complete combustion

Option C: High oxygen in flue gas

Option D: None of these

Correct Answer: Complete combustion ✔

Option A: Fischer-Tropsch

Option B: Bergius

Option C: Lurgi

Option D: None of these

Correct Answer: Bergius ✔

Option A: 11.5

Option B: 0.5

Option C: 23

Option D: 12

Correct Answer: 11.5 ✔

Option A: CO2

Option B: CO

Option C: O2

Option D: C

Correct Answer: CO ✔

Option A: As moisture proof coating on fibres

Option B: As moth balls (insecticides)

Option C: As a fuel in furnaces

Option D: For making electrodes

Correct Answer: As moth balls (insecticides) ✔

Option A: Coal can be pulverised with great difficulty

Option B: Coal can’t be pulverised

Option C: Coal can be easily pulverised

Option D: Power consumption in grinding the coal will be very high

Correct Answer: Coal can be easily pulverised ✔

Option A: Gas yield is less

Option B: Tar yield is more

Option C: Ignition temperature of coke produced is less

Option D: Aromatic content of tar produced is more

Correct Answer: Aromatic content of tar produced is more ✔

Option A: Furnace oil

Option B: Bagasse

Option C: Semi-coke

Option D: Kerosene

Correct Answer: Bagasse ✔

Option A: To check against its excessive swelling during heating, which may exert high pressure and

Option B: Because, it alone produces unreactive coke

Option C: Both A. and B.

Option D: Neither A. nor B.

Correct Answer: C. Both A. and B. ✔

Option A: 300

Option B: 1100

Option C: 700

Option D: 150

Correct Answer: 700 ✔

Option A: Increase

Option B: Decrease

Option C: Remain unchanged

Option D: May increase or decrease; depends on the quantity of products of combustion

Correct Answer: May increase or decrease; depends on the quantity of products of combustion ✔

Option A: It cannot burn low grade coal

Option B: It achieves higher fuel combustion efficiency

Option C: Less heat transfer surface area is required in boilers

Option D: None of these

Correct Answer: It cannot burn low grade coal ✔

Option A: % of CO2 in

Option B: % of O2in

Option C: Temperature of

Option D: Colour of

Correct Answer: % of O2in ✔

Option A: Flame length

Option B: Flame temperature

Option C: Quantity of flue gas

Option D: Ignition temperature

Correct Answer: Flame temperature ✔

Option A: M = 1.1A

Option B: M = A

Option C: M = 1.5A

Option D: M = 2A

Correct Answer: M = 1.1A ✔

Option A: Sewage gas

Option B: LPG

Option C: Producer gas

Option D: Natural gas

Correct Answer: LPG ✔

Option A: More explosive and inflammable

Option B: Less poisonous

Option C: Lighter

Option D: All A., B. and C.

Correct Answer: D. All A., B. and C. ✔

Option A: 2CO ↔ C + CO2

Option B: CO + H2O ↔ CO2 + H2

Option C: C + H2O ↔ CO + H2

Option D: C + 2H2O ↔ CO2 + 2H2

Correct Answer: 2CO ↔ C + CO2 ✔

Option A: 1,800

Option B: 3,200

Option C: 5,400

Option D: 10,200

Correct Answer: 5,400 ✔

Option A: Higher calorific value at constant volume

Option B: Gross calorific value at constant pressure

Option C: Lower calorific value at constant pressure

Option D: Net calorific value at constant volume

Correct Answer: Higher calorific value at constant volume ✔

Option A: Silica gel

Option B: Diatomaceous earth

Option C: Basalt

Option D: Bog iron (i.e., moist ferric hydroxide)

Correct Answer: Bog iron (i.e., moist ferric hydroxide) ✔

Option A: Coal

Option B: Kerosene

Option C: Natural gas

Option D: Furnace oil

Correct Answer: Furnace oil ✔

Option A: 1100

Option B: 1250

Option C: 1350

Option D: 1400

Correct Answer: 1100 ✔

Option A: 10,000

Option B: 2,500

Option C: 25,000

Option D: 35,000

Correct Answer: 10,000 ✔

Option A: Decrease in its calorific value

Option B: Increase in its strength

Option C: Brittleness of steel made by using it

Option D: None of these

Correct Answer: Brittleness of steel made by using it ✔

Option A: Low ignition temperature

Option B: Very little ash content

Option C: High fusion point of its ash

Option D: Low adiabatic flame temperature

Correct Answer: Low ignition temperature ✔

Option A: Calorific value, cleanliness and relatively low distribution cost (due to its low specific gravity)

Option B: Adiabatic flame temperature

Option C: Heat release rate (thus requiring smaller combustion chamber)

Option D: All A., B. and C.

Correct Answer: D. All A., B. and C. ✔

Option A: Micrinite

Option B: Clarain

Option C: Fusinite

Option D: Liptinite

Correct Answer: Clarain ✔

Option A: Coke oven gas

Option B: Furnace oil

Option C: Pulverised coal

Option D: Lump coal (fixed on chain grate)

Correct Answer: Lump coal (fixed on chain grate) ✔

Option A: 6

Option B: 18

Option C: 28

Option D: 36

Correct Answer: 18 ✔

Option A: Increases

Option B: Decreases

Option C: Remain same

Option D: May increase or decrease; depends on the type of fuel

Correct Answer: Decreases ✔

Option A: 2000

Option B: 600

Option C: 1100

Option D: 1600

Correct Answer: 1100 ✔

Option A: Deoxidation

Option B: Gasification

Option C: Coalification

Option D: Carbonisation

Correct Answer: Carbonisation ✔

Option A: Coke oven gas

Option B: Water gas

Option C: Natural gas

Option D: Blast furnace gas

Correct Answer: Blast furnace gas ✔

Option A: Low fusion point of ash

Option B: High ash content

Option C: High sulphur

Option D: None of these

Correct Answer: None of these ✔

Option A: 80 and 97

Option B: 95 and 100

Option C: 40 and 70

Option D: 25 and 97

Correct Answer: 80 and 97 ✔

Option A: Thickness of plastic layer

Option B: Caking index

Option C: Swelling index

Option D: Gray-king index

Correct Answer: Caking index ✔

Option A: Tar

Option B: Benzol

Option C: Ammonia

Option D: None of these

Correct Answer: Ammonia ✔

Option A: Storage in large heaps

Option B: Storage in compressed piles

Option C: Absence of porous or friable particles

Option D: All A., B. and C.

Correct Answer: Storage in large heaps ✔

Option A: Decreases

Option B: Increases

Option C: Remain same

Option D: May increase or decrease depending on the type of fuel

Correct Answer: Increases ✔

Option A: The gaseous fuel before combustion decreases

Option B: Combustion air decreases

Option C: Either the fuel or the air or both, increases

Option D: Either the fuel or the air does not affect

Correct Answer: Either the fuel or the air or both, increases ✔

Option A: Hydrogen

Option B: Methane

Option C: Unsaturated hydrocarbons

Option D: All A., B. and C.

Correct Answer: Hydrogen ✔

Option A: O2

Option B: CO

Option C: N2

Option D: SO2

Correct Answer: O2 ✔

Option A: Transportation and handling

Option B: Washing

Option C: Pulverisation

Option D: Storage

Correct Answer: Pulverisation ✔

Option A: Are soft & friable (poor strength and size stability)

Option B: Require longer time of carbonisation as ash offers resistance to heat transfer

Option C: Produce larger quantity of coke oven gas

Option D: None of these

Correct Answer: Require longer time of carbonisation as ash offers resistance to heat transfer ✔

Option A: Humidity of combustion air

Option B: Moisture content of fuel

Option C: Both A. and B.

Option D: The water formed by combustion reaction

Correct Answer: C. Both A. and B. ✔