Fuels and Combustion

Question: A coal having high volatile matter content will
[A].

give less yield of tar and gas on carbonisation.

[B].

burn with a small non-smoky flame.

[C].

have a very high calorific value.

[D].

none of these.

Answer: Option D

Explanation:

No answer description available for this question.

Question: A good coking coal should have high __________ content.
[A].

ash

[B].

sulphur & phosphorus

[C].

moisture

[D].

none of these

Answer: Option D

Explanation:

No answer description available for this question.

Question: Fuel consumption in coke making can be reduced by
[A].

preheating, blending and de-ashing the coal.

[B].

stamped charging of coal.

[C].

dry quenching of coke.

[D].

all (a), (b) and (c).

Answer: Option D

Explanation:

No answer description available for this question.

Question: Narrow coke ovens as compared to wider coke ovens
[A].

produce smaller coke.

[B].

produce stronger coke.

[C].

require less time of carbonisation.

[D].

all (a), (b) and (c).

Answer: Option D

Explanation:

No answer description available for this question.

Question: Coke having higher porosity has
[A].

lower bulk density.

[B].

lower strength.

[C].

higher reactivity.

[D].

all (a), (b) and (c).

Answer: Option D

Explanation:

No answer description available for this question.

Question: Which will have the least volatile matter and hence will be the most difficult to ignite?
[A].

Bituminous coal

[B].

Coke

[C].

Semi-bituminous coal

[D].

Aanthracite

Answer: Option B

Explanation:

No answer description available for this question.

Question: With increase in moisture content of coal, its
[A].

calorific value increases.

[B].

caking properties diminish.

[C].

swelling during carbonisation becomes excessive.

[D].

none of these.

Answer: Option B

Explanation:

No answer description available for this question.

Question: Width of the coke oven towards coke side is slightly more than that on pusher side to
[A].

facilitate easy discharging of coke as it swells during carbonisation.

[B].

facilitate uniform heating of the oven.

[C].

increase the output of the coke.

[D].

none of these.

Answer: Option A

Explanation:

No answer description available for this question.

Question: During the carbonisation of coal
[A].

all tar is evolved at < 600°C.

[B].

evolution of H2 and formation of methane and aromatics occur at > 700°C.

[C].

hard semi-coke starts shrinking at 600°C.

[D].

all (a), (b) and (c).

Answer: Option D

Explanation:

No answer description available for this question.

Question: Low temperature carbonisation
[A].

is mainly for producing the smokeless domestic coke.

[B].

is meant for the production of ‘metallurgical coke’.

[C].

produces higher quantity of gas than high temperature carbonisation.

[D].

produces less quantity of tar than high temperature carbonisation.

Answer: Option A

Explanation:

No answer description available for this question.