Chemical Engineering - Fuels and Combustion

26. 

Ignition temperature decreases progressively from anthracite to lignite, because

A. volatile matter content increases.
B. carbon content decreases.
C. moisture content increases.
D. ash content increases.

Answer: Option A

Explanation:

No answer description available for this question. Let us discuss.

27. 

Which of the following fuel gases is heavier than air ?

A. Blast furnace gas
B. Coke oven gas
C. Natural gas
D. Water gas

Answer: Option A

Explanation:

No answer description available for this question. Let us discuss.

28. 

Correct viscosity of furnace oil at the burner tip for proper atomisation is about 25 centistokes. To reduce the viscosity of high viscosity furnace oil (250 centistokes) to the correct atomisation viscosity (i.e. 25 cst), it should be preheated to about____°C.

A. 70
B. 85
C. 105
D. 145

Answer: Option C

Explanation:

No answer description available for this question. Let us discuss.

29. 

Theoretical flame temperature of a fuel is that temperature which is attained, when the fuel is completely burnt 'using theoretical amount of air in

A. air
B. oxygen
C. either (a) or (b)
D. either (a) or (b) without gain or loss of heat

Answer: Option D

Explanation:

No answer description available for this question. Let us discuss.

30. 

Use of preheated air for combustion of fuel in the furnace, increases the

A. scale losses of the furnace stock.
B. calorific value of the fuel.
C. flame temperature.
D. none of these.

Answer: Option C

Explanation:

No answer description available for this question. Let us discuss.