Fuels and Combustion MCQs

Question 1

High amount of sulphur and phosphorous in coke causes

Accepted Answer

Brittleness of steel made by using it

Answer

Decrease in its calorific value

Answer

Increase in its strength

Answer

None of these

Question 2

Which of the following constituents of coal is the most important in the production of coke?

Accepted Answer

Carbon

Answer

Moisture

Answer

Ash

Answer

Volatiles

Question 3

Benzol is used

Accepted Answer

Both A & B

Answer

As a motor fuel blend

Answer

For producing benzene, tolune & xylene by its distillation

Answer

Neither A nor B

Question 4

Coking time in a commercial high temperature coal carbonisation plant is about __________ hours.

Accepted Answer

18

Answer

6

Answer

28

Answer

36

Question 5

Pick out the wrong statement.

Accepted Answer

Specific heat of coal decreases with increases in the volatile matter and decrease in the C/H ratio of coal

Answer

Angle of repose of coal increases with its increasing size

Answer

Specific gravity of coal increases with its increasing maturity

Answer

Refractive index and reflectance of coal increases with the increasing rank of coal

Question 6

Anthracite can be used for

Accepted Answer

All of the above

Answer

Recarbonising steel

Answer

Making carbon electrodes

Answer

Blending with highly coking coal to check its swelling which helps in saving coke even walls from damage and to produce high strength coke

Question 7

Anthracite coal

Accepted Answer

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

Answer

Contains more volatile matter than bituminous coal

Answer

Ignites more easily than bituminous coal

Answer

Is essentially a coking coal

Question 8

Ignition temperature decreases progressively from anthracite to lignite, because

Accepted Answer

Volatile matter content increases

Answer

Carbon content decreases

Answer

Moisture content increases

Answer

Ash content increases

Question 9

Blast furnace gas is a very poisonous gas because of its predominantly high __________ content.

Accepted Answer

CO

Answer

H2O

Answer

CO2

Answer

CH4