Chemical Engineering

Question: Heat transfer rate to the charge/stock in a furnace does not depend upon the
[A].

type of fuels viz solid, liquid or gaseous.

[B].

flue gas temperature.

[C].

emissivity of refractory walls.

[D].

initial temperature of the charged stock.

Answer: Option A

Explanation:

No answer description available for this question.

Question: In practical operation of any furnace, zero oxygen percentage or theoretical CO2 percentage in flue gas is rarely achieved, because of
[A].

use of non-preheated combustion air.

[B].

use of pulverised solid fuels.

[C].

imperfect mixing of fuel & air and infiltration of air.

[D].

use of excessive positive draft in the furnace.

Answer: Option C

Explanation:

No answer description available for this question.

Question: Overall thermal efficiency of a lumpy coal fired suitably designed heating furnace, if operated & maintained properly may be about __________ percent.
[A].

10-15

[B].

25-30

[C].

45-50

[D].

65-70

Answer: Option B

Explanation:

No answer description available for this question.

Question: __________ is an indirectly heated furnace.
[A].

Open hearth furnace

[B].

Muffle furnace

[C].

Soaking pit

[D].

Reheating furnace

Answer: Option B

Explanation:

No answer description available for this question.

Question: An improved and fuel efficient version of the pusher type reheating furnace is the __________ furnace.
[A].

walking beam

[B].

shaft

[C].

tunnel

[D].

rotary hearth

Answer: Option A

Explanation:

No answer description available for this question.

Question: Neutral atmosphere is maintained in a/an __________ furnace.
[A].

cold rolled steel coil annealing

[B].

open hearth

[C].

soaking pit

[D].

walking beam reheating

Answer: Option A

Explanation:

No answer description available for this question.

Question: Maximum heat transfer in high temperature furnaces is by
[A].

conduction

[B].

convection

[C].

radiation

[D].

either (a), (b) or (c); depends on the type of furnace

Answer: Option C

Explanation:

No answer description available for this question.

Question: Oxygen enrichment of combustion air does not result in increase of the
[A].

flame temperature.

[B].

oxygen in the flue gas.

[C].

stack loss.

[D].

heat transfer rate in the furnace.

Answer: Option B

Explanation:

No answer description available for this question.

Question: Low stack loss indicates the
[A].

use of sub-stoichiometric air for combustion.

[B].

efficient use of fuel.

[C].

inefficient use of fuel.

[D].

oxygen enrichment of combustion air.

Answer: Option B

Explanation:

No answer description available for this question.

Question: Acid dew point temperature (ADT) of a flue gas produced by the combustion of a fuel containing 1% sulphur may be about __________ °C.
[A].

80

[B].

130

[C].

180

[D].

250

Answer: Option B

Explanation:

No answer description available for this question.