Fuels and Combustion MCQs

Question 1

Fuel for a nuclear reactor (thermal) is

Accepted Answer

Uranium

Answer

Plutonium

Answer

Radium

Answer

None of these

Question 2

Pick out the wrong statement.

Accepted Answer

Calorific value of natural gas is more than that of LPG

Answer

High concentration of oxygen in flue gas means high stack loss

Answer

Gaseous fuels require the least % excess air for complete combustion

Answer

The ratio of fixed carbon to volatile matter percentage in coal is called its 'fuel ratio'

Question 3

Very __________ coals are completely devoid of cokability i.e, it is non coking.

Accepted Answer

Both A & B

Answer

Young

Answer

Mature

Answer

Neither A nor B

Question 4

Dust content in raw blast furnace gas is about __________ gm/Nm3, hence it is cleaned to the dust level of about < 10 mg/Nm3 before use.

Accepted Answer

15 - 30

Answer

1 - 2

Answer

70 - 100

Answer

150 - 200

Question 5

Coke oven gas is a better fuel than blast furnace gas, because of its higher

Accepted Answer

All of the above

Answer

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

Answer

Adiabatic flame temperature

Answer

Heat release rate (thus requiring smaller combustion chamber)

Question 6

The main advantage of forced draft over natural draft is that

Accepted Answer

All of the above

Answer

Combustion of fuel is complete

Answer

Smaller height chimney can be used

Answer

Furnace control is easier

Question 7

A particular coal is said to be free burning when it

Accepted Answer

Shows little or no fusing action

Answer

Burns completely

Answer

Gives smokeless burning

Answer

None of these

Question 8

Main constituents of benzol are

Accepted Answer

Benzene, toluene & xylene

Answer

Tar & creosote

Answer

Ammonia & phenol

Answer

Anthracene & phenol

Question 9

A coal containing very high percentage of durain is called __________ coal.

Accepted Answer

Splint

Answer

Bright

Answer

Non-banded

Answer

Boghead