DAPZOI
Home Ask MCQ Quiz Topics Login


Furnace Technology MCQ Questions & Answers

Furnace Technology MCQs : This section focuses on the "Furnace Technology". These Multiple Choice Questions (MCQs) should be practiced to improve the Furnace Technology skills required for various interviews (campus interview, walk-in interview, company interview), placement, entrance exam and other competitive examinations.




Question 1

Thermal efficiency of blast furnace stoves used for heating blast (air) may be about __________ percent.

A. 20
B. 40
C. 60
D. 80

View Answer

Question 2

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

View Answer

Question 3

Which furnace employs preheating, heating and soaking zones ?

A. Soaking pit
B. Reheating furnace
C. Open hearth furnace
D. Cupola

View Answer

Question 4

Ceramic recuperators compared to metallic recuperators for the same duty

A. are lighter.
B. occupy more space.
C. are less costly.
D. have higher pressure differential between flue gas & air side.

View Answer

Question 5

Thickness of stock does not affect the fuel economy of furnaces, if the material to be heated is of

A. low emissivity
B. high thermal conductivity
C. both (a) and (b)
D. neither (a) nor (b)

View Answer

Question 6

Fuel used in B.F. stove is

A. pulverised coal
B. furnace oil
C. blast furnace gas/mixed gas
D. coke oven gas

View Answer

Question 7

An example of shaft furnace is the

A. L.D. converter
B. glass melting tank
C. blast furnace
D. soaking pit

View Answer

Question 8

Which of the following is not a directly fired furnace ?

A. By-product coke oven
B. Calcination kiln
C. Sintering furnace
D. Open hearth furnace

View Answer

Question 9

Calcination of limestone to produce lime is done in a __________ kiln.

A. tunnel
B. rotary
C. vertical shaft
D. both (b) and (c)

View Answer

Question 10

In a muffle furnace, the muffle

A. retards the heat transfer.
B. assists in temperature equalisation in the charge.
C. permits the use of controlled atmosphere for the protection of stock.
D. all (a), (b) and (c).

View Answer

Question 11

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

View Answer

Question 12

Regenerators are installed in

A. coke ovens
B. open hearth furnace
C. both (a) & (b)
D. neither (a) nor (b)

View Answer

Question 13

Means for giving direction to the circulation of gases in furnaces are

A. fans.
B. arrangement of heating stock in the furnaces.
C. location of outlet ports and heating & combustion devices.
D. all (a), (b) and (c).

View Answer

Question 14

Which is a continuous furnace ?

A. Coke ovens
B. Annealing furnace
C. Glass tank furnace
D. None of these

View Answer

Question 15

Which of the following is a heat treatment furnace ?

A. Muffle furnace
B. Annealing furnace
C. Reheating furnace
D. Rotary kiln

View Answer

Question 16

Which is the most thermally efficient furnace ?

A. Reheating furnace
B. Reverberatory furnace
C. Rotary kilns
D. Boiler furnace

View Answer

Question 17

To reduce the stack loss, heat recovery from flue gas can be done by

A. preheating of cold stock.
B. preheating of combustion air.
C. steam generation in waste heat boilers.
D. all (a), (b) and (c).

View Answer

Question 18

In producer gas making furnace, steam is added along with air to mainly control the

A. fusion of coal ash & clinker formation.
B. C. V. of producer gas.
C. temperature of producer gas.
D. tar content in producer gas.

View Answer

Question 19

The purpose of controlling the furnace atmosphere is to prevent surface attack by

A. oxidation/scaling
B. decarburising
C. sulphur penetration
D. either of the above

View Answer

Question 20

Cement Kiln is a

A. rotary Kiln
B. tunnel Kiln
C. natural draft furnace
D. batch furnace

View Answer

Question 21

The thermal efficiency of an air/fuel gas preheating recuperator may be as high as __________ percent.

A. 50
B. 65
C. 85
D. 99

View Answer

Question 22

Which is not a hearth furnace ?

A. Glass tank furnace
B. Open hearth furnace
C. Cupola
D. Reheating furnace

View Answer

Question 23

Soaking pits are meant for heating steel

A. ingots
B. coils
C. sheets
D. slabs

View Answer

Question 24

Pulverised fuel fired furnaces employ __________ fuel firing.

A. horizontal
B. vertical
C. tangential
D. all (a), (b) and (c)

View Answer

Question 25

Example of an indirectly heated furnace is

A. hood annealing furnace
B. muffle furnace
C. both (a) and (b)
D. neither (a) nor (b)

View Answer

Question 26

Ceramic coating material for furnace refractory, which increases its emissivity and thus the radiation heat transfer rate in the furnace, comprises of

A. graphite powder
B. thoria
C. zircon powder
D. beryllium

View Answer

Question 27

The reason for excessive clinker formation in gas producers is the

A. use of coal/coke containing a high % of fines and ash.
B. use of fuel having too low an ash fusion temperature.
C. development of hot spots in the fuel bed and an abnormally high rate of gasification.
D. all (a), (b) and (c).

View Answer

Question 28

Which of the following is a natural draft furnace ?

A. Blast furnace stoves
B. Power plant boilers
C. Sintering furnace
D. None of these

View Answer

Question 29

Tunnel kilns are usually used for

A. roasting of pyrites.
B. drying/tempering of refractories.
C. reheating of slabs.
D. melting of glass.

View Answer

Question 30

Thermal efficiency of a limestone calcination rotary kiln may be around __________ percent.

A. 20
B. 40
C. 65
D. 80

View Answer

Question 31

Large tonnage of refractory bricks are dried in a

A. shaft furnace
B. rotary hearth furnace
C. tunnel kiln
D. muffle furnace

View Answer

Question 32

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

A. 250
B. 650
C. 850
D. 1000

View Answer

Question 33

__________ is an indirectly heated furnace.

A. Open hearth furnace
B. Muffle furnace
C. Soaking pit
D. Reheating furnace

View Answer

Question 34

The heat recoverable from flue gases of furnaces depends on the

A. thermal efficiency of furnace.
B. quantity of flue gases.
C. flue gas temperature drop through the furnace.
D. all (a), (b) and (c).

View Answer

Question 35

An example of a periodic furnace is the

A. blast furnace stoves
B. blast furnace
C. coke oven heating chamber
D. rotary kilns

View Answer

Question 36

Heat transfer rate to the stock/charge in the furnace does not depend upon the

A. emissivity of the refactory walls.
B. size of the furance.
C. use of waste heat recovery equipments.
D. thickness of the stock.

View Answer

Question 37

The thermal efficiency of a steel slab reheating furnace (walking beam type) may be about __________ percent.

A. 15
B. 40
C. 70
D. 85

View Answer

Question 38

Which of the following is not an additive for flue gases from furnace to reduce its dew-point?

A. Ammonia
B. Fine dolomite
C. Alkaline powders
D. None of these

View Answer

Question 39

Ostwald charts are meant for

A. computing the excess/deficiency of combustion air.
B. calculation of flue gas temperature.
C. computation of flue gas analysis.
D. none of these.

View Answer

Question 40

Temperature of a furnace fired with low calorific value fuel gas (i.e. lean gas) can be increased by

A. preheating the combustion air.
B. oxygen enrichment of combustion air.
C. preheating the fuel gas.
D. all (a), (b) & (c).

View Answer

Question 41

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.

View Answer

Question 42

The amount of combustible escaping uncon-sumed from the furnace, depends upon the

A. air supplied and furnace temperature.
B. burner design (thoroughness of mixing versus stratification).
C. air preheat and the flow of gases in the furnace (mixing by induction, by acceleration or by change of direction).
D. all (a), (b) and (c).

View Answer

Question 43

Higher furnace temperature can not be achieved by use of a lean fuel gas in the furnace by

A. increasing the draft in the furnace.
B. preheating the fuel gas.
C. oxygen enrichment of combustion air.
D. preheating the combustion air.

View Answer

Question 44

Which of the following is the most suitable for preheating combustion air above 650°C ?

A. Regenerator
B. Metallic recuperator
C. Ceramic recuperator
D. None of these

View Answer

Question 45

Coke ovens in steel plant are heated by

A. electricity
B. blast furnace gas/mixed gas
C. coke oven gas
D. both (b) and (c)

View Answer

Question 46

__________ atmosphere is maintained inside an iron blast furnace.

A. Oxidising
B. Reducing
C. Inert
D. Decarburising

View Answer

Question 47

In a furnace employing forced draught as compared to induced draught,

A. air is sucked in, so air leaks are more and hence the furnace efficiency is reduced.
B. the fan operates hot and hence blades are liable to corrosion and erosion.
C. positive pressure exists in the furnace.
D. none of these

View Answer

Question 48

In reverberatory furnace, charge is heated mainly by

A. conduction.
B. natural convection.
C. radiation of heat from the roof of the combustion chamber.
D. none of these.

View Answer

Question 49

In order to maintain a reducing atmosphere in a furnace, it should have

A. no O2 in flue gas
B. CO in flue gas
C. high excess air
D. none of these

View Answer