High rank coals have higher amount of volatile matter
Ratio of fixed carbon to volatile matter increases
Oxygen content progressively decreases
Calorific value of the coal increases
✅ The correct answer is option B.
Fuel and Combustion MCQs
Which of the following is unsuitable fuel for producer gas manufacture?
Coke
Anthracite
Coal having low fusion point of its ash
Coal having high fusion point of its ash
✅ The correct answer is option C.
Traces of tar fog present in the coke oven gas is removed by
Cyclone separator
Wet packed scrubber
Electrostatic precipitator
Washing with monoethanolamine
✅ The correct answer is option C.
Which of the following has the highest heat of combustion?
H₂
CO
CH₄
C₂H₆
✅ The correct answer is option D.
The optimum percentage of excess air for combustion depends upon the __________ of the fuel.
Type (solid, liquid or gaseous)
Calorific value
Sulphur content
Ignition temperature
✅ The correct answer is option A.
Cannel coal
Is non-coking
Has a high volatile matter content and burns with a luminous smoky flame
Is a non-banded coal which can be ignited easily with a match stick or candle flame, hence is so named
All of the above
✅ The correct answer is option D.
A sooty flame can be made non-luminous by
Admitting more gas
Shutting gas supply
Admitting more air
Shutting air supply
✅ The correct answer is option C.
Which of the following constituents of a fuel does not contribute to its calorific value on combustion?
Hydrogen
Sulphur
Carbon
None of these
✅ The correct answer is option D.
Which of the following is the most reactive (as regards the formation of CO + H₂ from C + H₂O) ?
Blast furnace coke
Low temperature coke
Anthracite coal
Sub-bituminous coal
✅ The correct answer is option B.
A coal containing very high percentage of durain is called __________ coal.
Bright
Splint
Non-banded
Boghead
✅ The correct answer is option B.