Fuels and Combustion

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

swelling characteristics.

[B].

abradability.

[C].

agglutinating properties.

[D].

resistance to impact breakage.

Answer: Option A

Explanation:

No answer description available for this question.

Question: Abrasion index of blast furnace coke should be around __________ percent.
[A].

20

[B].

35

[C].

55

[D].

80

Answer: Option D

Explanation:

No answer description available for this question.

Question: Heat penetration rate in narrow coke ovens in high temperature carbonisation of coal is around __________ cm/hr.
[A].

2.5

[B].

0.5

[C].

10

[D].

20

Answer: Option A

Explanation:

No answer description available for this question.

Question: In high temperature carbonisation (as compared to low temperature carbonisation) of coal
[A].

coke oven gas yield is more.

[B].

tar yield is less but free carbon in tar is more.

[C].

calorific value of coke oven gas is less.

[D].

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

Answer: Option D

Explanation:

No answer description available for this question.

Question: Desirable “Micum Index” values of metal-lurical coke are
[A].

M40 > 78% and M10 < 10%.

[B].

M40 > 4% and M10 < 80%.

[C].

M40 > 10% and M10 < 78%.

[D].

M40 > 98% and M10 < 2%.

Answer: Option A

Explanation:

No answer description available for this question.

Question: “Micum Index” of a coke is a measure of its
[A].

reactivity.

[B].

porosity.

[C].

bulk density.

[D].

hardness & strength.

Answer: Option D

Explanation:

No answer description available for this question.

Question: Critical Air Blast (CAB) value of coke is a direct measure of its
[A].

reactivity

[B].

hardness

[C].

strength

[D].

none of these

Answer: Option A

Explanation:

No answer description available for this question.

Question: Caking index of the coal blend used for the manufacture of metallurgical coke should be around
[A].

5

[B].

21

[C].

40

[D].

48

Answer: Option B

Explanation:

No answer description available for this question.

Question: Beehive coke oven
[A].

facilitates by-products recovery.

[B].

takes 2-3 days for coking of coal but requires no external fuel for heating.

[C].

gives larger yield of coke (around 85%) as compared to by-product ovens.

[D].

produces coke with very poor strength.

Answer: Option B

Explanation:

No answer description available for this question.

Question: Coking time in narrow by-product coke ovens is around __________ hours.
[A].

18

[B].

48

[C].

8

[D].

80

Answer: Option A

Explanation:

No answer description available for this question.