High volatile matter
Low ash
High calorific value
High ash
✅ The correct answer is option A.
Fuel and Combustion MCQs
Ash content in the middling coal (a byproduct of coal washeries) in India ranges between __________ percent.
15 to 25
35 to 45
55 to 75
75
✅ The correct answer is option B.
Size of blast furnace grade coke is __________ mm.
25-80
0-15
15-25
>100
✅ The correct answer is option A.
Coke oven gas is a better fuel than blast furnace gas, because of its higher
Calorific value, cleanliness and relatively low distribution cost (due to its low specific gravity)
Adiabatic flame temperature
Heat release rate (thus requiring smaller combustion chamber)
All of the above
✅ The correct answer is option D.
Presence of free moisture in coal is most disadvantageous during
Its pulverisation (as it requires more power)
Combustion of fire slacks on the grates
Handling (e.g. when emptying wagons)
None of these
✅ The correct answer is option A.
Wood charcoal is obtained by the destructive distillation of wood. It is used in the production of activated carbon, which is not used for the
Decolourisation of sugar
Solvent recovery from air and gases
Absorption of gases and vapor
Electrode manufacture
✅ The correct answer is option D.
Which is the heaviest fuel gas out of the following?
Blast furnace gas
Coke oven gas
Water gas
Carburetted water gas
✅ The correct answer is option A.
The hottest part of the flame lies in its____zone.
Non-luminous
Luminous
Yellow
Unburnt gases
✅ The correct answer is option A.
Which of the following has the highest theoretical flame temperature ?
Blast furnace gas
Hydrogen
Acetylene
Coke oven gas
✅ The correct answer is option C.
Spontaneous combustion of coal on storage results due to
Inadequate ventilation
Low temperature oxidation
Storage in large heaps with small surface to volume ratio
All of the above
✅ The correct answer is option D.