Washing of coal decreases its_________________?

Question: Low temperature oxidation and spontaneous combustion of freshly mined coal is accentuated, if
[A].

it contains large amount of volatile matter.

[B].

it is stored in tall heaps.

[C].

smaller fines are stored in large quantity.

[D].

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

Answer: Option D

Explanation:

No answer description available for this question.

Question: The calorific value of ‘LPG’ (50% propane + 50% butane) is about __________ kcal/Nm3.
[A].

5000

[B].

25, 000

[C].

10, 000

[D].

15, 000

Answer: Option B

Explanation:

No answer description available for this question.

Question: In case of pulverised coal fired steam boiler, the secondary air serves the main purpose of
[A].

transportation of coal.

[B].

drying of coal.

[C].

combustion of coal by supplying it around the burner.

[D].

preheating the primary air.

Answer: Option C

Explanation:

No answer description available for this question.