200 meters
Infinitely long
More than 105.7 metres
Equal to the height of the hot gas column producing draught
✅ The correct answer is option D.
Fuel and Combustion MCQs
Coking time in beehive coke oven is about
12 hours
2-3 days
One week
Two weeks
✅ The correct answer is option B.
Supply of excess air for complete combustion of fuel is necessitated to facilitate
Its thorough mixing with air
Attainment of chemical equilibrium
Attainment of high temperature
None of these
✅ The correct answer is option A.
Yield of pitch from distillation of high temperature tar is around __________ percent.
10
25
65
90
✅ The correct answer is option C.
Rate of low temperature oxidation of coal due to bad storage conditions
Decreases with increase in surface area
Does not vary with increase in surface area
Is more for low volatile coal compared to high volatile coal
Is accelerated by storage in large heaps with small surface to volume ratio
✅ The correct answer is option D.
In flue gas analysis by Orsat’s apparatus, carbon dioxide is absorbed by
Potassium hydroxide
Dilute potassium carbonate
Cuporus chloride
Alkaline pyragllol solution
✅ The correct answer is option A.
The calorific value of producer gas is around __________ kcal/Nm³
1300
500
4500
9000
✅ The correct answer is option A.
Blast furnace gas is a very poisonous gas because of its predominantly high __________ content.
H₂O
CO₂
CO
CH₄
✅ The correct answer is option C.
A sample of natural gas containing 80% methane (CH₄) and rest nitrogen (N₂) is burnt with 20% excess air. With 80% of the combustibles producing CO₂ and the reminder going to CO, the Orsat analysis in volume percent is
CO₂ : 6.26, CO : 1.56, O₂ : 3.91, H₂O :15.66, N₂ : 72.60
CO₂ : 7.42, CO : 1.86, O₂ : 4.64, N₂:86.02
CO₂ : 6.39, CO : 1.60, O₂ : 3.99, H₂O:25.96, N₂:72.06
CO₂ : 7.60, CO : 1.90, O₂ : 4.75, N₂ : 85.74
✅ The correct answer is option B.
Which of the following is not a product of tar distillation?
Phenol & naphthalene
Benzol & pitch
Anthracene & creosote
None of these
✅ The correct answer is option D.