161. Ammonia content in raw coke oven gas is about __________ gm/Nm³.
1
15
50
100
✅ The correct answer is option B.
Fuel and Combustion MCQs
162. Benzol is used
As a motor fuel blend
For producing benzene, tolune & xylene by its distillation
Both A & B
Neither A nor B
✅ The correct answer is option C.
163. Fusion point of coal ash increases with increase in its __________ content.
Iron sulphate
Iron silicate
Lime and magnesia
All of the above
✅ The correct answer is option D.
164. High amount of sulphur and phosphorous in coke causes
Decrease in its calorific value
Increase in its strength
Brittleness of steel made by using it
None of these
✅ The correct answer is option C.
165. Coke oven gas compared to blast furnace gas is
More explosive and inflammable
Less poisonous
Lighter
All of the above
✅ The correct answer is option D.
166. Coke made in narrower by-product coke ovens (as compared to wider ovens) is
Less reactive
Stronger
Smaller in size
All of the above
✅ The correct answer is option D.
167. The calorific value of a gas of composition CO₂ = 20%, H₂ = 50%, CH₄ = 30%, is y. If the composition of gas is changed to H₂ = 50%, CH₄ = 30%, CO₂ = 10%, N₂ = 10%, then the calorifice value will be
Y
0.95 y
1.05 y
1.8 y
✅ The correct answer is option A.
168. Presence of phosphorous in metallurgical coal
Is not undersirable
Reduces its calorific value
Badly affects the quality of steel
Increases its caking power
✅ The correct answer is option C.
169. Gas yield in the Kopper-Totzek coal gasifier is about __________ Nm³/ton coal (ash = 35%).
150
1500
3500
5000
✅ The correct answer is option B.
170. Function of secondary air in pulverised coal firing is to
Transport the coal to the burner
Dry the coal
Ensure efficient burning of coal around the burner
Reduce primary air requirement
✅ The correct answer is option C.