Inherent impurities
Adhering impurities
Mineral matter
Both B and C
✅ The correct answer is option D.
Fuel and Combustion MCQs
Coal tar fuel – 200 (CTF 200) is a mixture of
Pitch and creosote oil
Light oil and pitch
Anthracene and crecosote oil
Solar oil and pitch
✅ The correct answer is option A.
Anthracite can be used for
Recarbonising steel
Making carbon electrodes
Blending with highly coking coal to check its swelling which helps in saving coke even walls from damage and to produce high strength coke
All of the above
✅ The correct answer is option D.
Blast furnace gas compared to coke oven gas has
Lower ignition temperature
Narrower limit of inflammability
Higher calorific value
Lower theoretical flame temperature
✅ The correct answer is option D.
Pure carbon is completely burnt in oxygen. The flue gas analysis is 70%CO₂, 20%CO and 10%O₂. The percent excess oxygen used is
20
12.5
0
10
✅ The correct answer is option C.
Preheating of a gaseous fuel results in increased
Flame length
Flame temperature
Quantity of flue gas
Ignition temperature
✅ The correct answer is option B.
Combustion of pulverised coal as compared to that of lump coal
Develops a non-luminous flame
Develops a low temperature flame
Can be done with less excess air
Provides a lower rate of heat release
✅ The correct answer is option C.
Dry air required to burn 1 kg of carbon completely may be around __________ kg.
11
2
20
38
✅ The correct answer is option A.
__________ present in coal is not determined in its ultimate analysis.
Fixed carbon
Total carbon
Hydrogen
Nitrogen
✅ The correct answer is option A.
Initial pressure of oxygen introduced into the ‘bomb’ of the bomb calorimeter for determination of calorific value of coal/fuel oil may be around __________ atm.
3-May
25-30
60-65
95-100
✅ The correct answer is option B.