CHEMICAL ENGINEERING

Question: Overfire burning in a furnace is a phenomenon characterised by
[A].

supply of excess fuel.

[B].

supply of excess air.

[C].

burning carbon monoxide and other incombustible in upper zone of furnace by supplying more air.

[D].

none of these.

Answer: Option C

Explanation:

No answer description available for this question.

Question: While the fuel fired furnace can be used upto a maximum temperature of about 1700°C, the electric furnace can be used upto a temperature of about __________ °C.
[A].

2000

[B].

3000

[C].

4500

[D].

6000

Answer: Option C

Explanation:

No answer description available for this question.

Question: __________ furnace is not an electric furnace.
[A].

Arc

[B].

Induction

[C].

Pot

[D].

Resistance.

Answer: Option C

Explanation:

No answer description available for this question.

Question: In furnaces operating at very high temperature (say) 1250°C, e.g. soaking pit), the maximum heat transfer takes place by
[A].

conduction

[B].

convection

[C].

radiation

[D].

can not be predicted.

Answer: Option C

Explanation:

No answer description available for this question.

Question: Out of the following fuels used in a furnace exhausting flue gas at a temperature of 600°C, the percentage stack loss will be maximum in case of complete combustion of
[A].

furnace oil with air.

[B].

furnace oil with oxygen.

[C].

blast furnace gas with air.

[D].

blast furnace gas with oxygen.

Answer: Option C

Explanation:

No answer description available for this question.

Question: Combustion of furnace oil in a furnace (soaking pit) with preheated combustion air at 400°C results in saving of about __________ percent furnace oil as compared to its combustion with atmospheric air, if the flue gas outlet temperature from the soaking pit is 1200°C.
[A].

5

[B].

60

[C].

20

[D].

40

Answer: Option C

Explanation:

No answer description available for this question.

Question: Flue gas outlet temperature from the chimney of any furnace should be ideally about __________ °C.
[A].

50

[B].

100

[C].

150

[D].

250

Answer: Option C

Explanation:

No answer description available for this question.

Question: Large tonnage of refractory bricks are dried in a
[A].

shaft furnace

[B].

rotary hearth furnace

[C].

tunnel kiln

[D].

muffle furnace

Answer: Option C

Explanation:

No answer description available for this question.

Question: Ceramic recuperators (made of SiC) is economical, only when used for preheating combustion air above __________ °C.
[A].

250

[B].

650

[C].

850

[D].

1000

Answer: Option B

Explanation:

No answer description available for this question.

Question: Metallic recuperators are not used for waste heat recovery, if the hot flue gas temperature is above __________ °C, because corrosion prevails at higher temperatures.
[A].

350

[B].

750

[C].

1050

[D].

1250

Answer: Option B

Explanation:

No answer description available for this question.