Fuels and Combustion

Question: Lignite is
[A].

a high rank coal.

[B].

a coking coal.

[C].

can be used for gasification and steam generation.

[D].

a black banded coal which burns with a non-smoky yellowish flame.

Answer: Option C

Explanation:

No answer description available for this question.

Question: Oxygen content in a flue gas was found to be 4%. It implies that excess air used for combustion was around __________ percent.
[A].

4

[B].

96

[C].

20

[D].

40

Answer: Option C

Explanation:

No answer description available for this question.

Question: A carbonaceous fuel (containing no H2 or hydrocarbons) is burnt and the resulting flue gas contains 21% CO2. It means that
[A].

21% excess air has been used for combustion.

[B].

21% excess oxygen has been used for combustion.

[C].

complete combustion of fuel has taken place.

[D].

no excess air has been used for combustion.

Answer: Option C

Explanation:

No answer description available for this question.

Question: Efficiency of the combustion of a fuel is judged by the __________ the flue gas.
[A].

%of CO2 in

[B].

% of O2in

[C].

temperature of

[D].

colour of

Answer: Option B

Explanation:

No answer description available for this question.

Question: Gray-King Assay and Roga Index of coal is a measure of its
[A].

abradability.

[B].

grindability.

[C].

weathering properties.

[D].

caking and swelling properties.

Answer: Option D

Explanation:

No answer description available for this question.

Question: Gobar gas constitutes mainly of
[A].

CH4 & CO2

[B].

CO & CO2

[C].

CH4 & N2

[D].

CO & N2

Answer: Option A

Explanation:

No answer description available for this question.

Question: Blast furnace gas constitutes mainly of
[A].

N2 & CH4

[B].

N2 & H2

[C].

N2 & CO

[D].

CH4 & CO2

Answer: Option C

Explanation:

No answer description available for this question.

Question: Coke oven gas constitutes mainly of
[A].

H2 & CO

[B].

H2 & CH4

[C].

CH4 & CO

[D].

H2 & CO2

Answer: Option B

Explanation:

No answer description available for this question.

Question: Calorific value of bituminous coal may be around __________ Kcal/kg.
[A].

500

[B].

1500

[C].

6500

[D].

20000

Answer: Option C

Explanation:

No answer description available for this question.

Question: Coalification means the
[A].

process of conversion of lignite into anthracite.

[B].

underground gasification of coal.

[C].

complete combustion of coal.

[D].

direct hydrogenation of coal.

Answer: Option A

Explanation:

No answer description available for this question.