Multiple Choice Questions and Answers (MCQ) on Chemical Engineering Furnace Technology
01. In which of the following furnaces, the gases are sucked through the stock bed from below?
(A) Soaking pit
(B) Sintering machine
(C) Beehive oven
(D) None of these
Answer: Option B
02. 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
Answer: Option B
03. Test specimen for determination of refractoriness under load (RUL) of a refractory is heated in a
(A) Furnace employing neutral atmosphere
(B) Carbon resistance furnace
(C) Reducing atmosphere
(D) Furnace employing negative pressure
Answer: Option B
04. The heating capacity of continuous reheating furnace depends upon the
(A) Hearth area and furnace temperature
(B) Emissivity of the stock
(C) Ratio of wall surface to stock surface
(D) All (A), (B) and (C)
Answer: Option D
05. Which of the following variables affects the furnace capacity?
(A) Temperature of flue gas
(B) Thermal conductivity of stock
(C) Thickness of heating stock
(D) All (A), (B) and (C)
Answer: Option D
06. 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
Answer: Option D
07. Scaling of furnace stock is reduced by __________ in flue gas.
(A) CO
(B) H2
(C) High CO/CO2
(D) All (A), (B) & (C)
Answer: Option D
08. Which is not accomplished in an underfired furnace?
(A) Increase in heating capacity/m2 of floor space
(B) Elimination of cold spot at the bottom of the charge
(C) Reduction in the temperature of furnace gases
(D) Protection of the periphery of the charge from excessive radiation
Answer: Option A
09. 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
10. Circulation of gases in furnace is caused by the
(A) Change in volume during a change of temperature
(B) Difference in density between hot and cold gases
(C) Furnace pressure in conjunction with draft in flues
(D) All (A), (B) and (C)
Answer: Option D
11. Forced recirculation of furnace gases is practised
(A) To increase heat transfer by convection
(B) To ensure uniform temperature
(C) In furnaces, operating below 750°C
(D) All (A), (B) and (C)
Answer: Option D
12. Which of the following variables does not affect the furnace capacity?
(A) Size of the furnace
(B) Gas velocity in furnace
(C) Ratio of wall surface to surface of stock
(D) None of these
Answer: Option D
13. In a furnace, the heat taken by the charge/stock and the heat lost to the furnace structure & flue gases depends on the
(A) Rate of firing and emissivity of flame
(B) Thermal conductivity of the charge & structural materials of furnace
(C) Nature of process; whether batch, continuous or intermittent
(D) All (A), (B) and (C)
Answer: Option D
14. An example of a periodic furnace is the
(A) Blast furnace stoves
(B) Blast furnace
(C) Coke oven heating chamber
(D) Rotary kilns
Answer: Option A
15. 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
16. Which of the following advantages is not associated with the use of preheated air for combustion of a fuel in the furnace?
(A) Increase in calorific value of the fuel
(B) Increase in flame temperature
(C) Reduction in scale losses
(D) Saving in fuel consumption
Answer: Option A
17. Which of the following is a batch furnace?
(A) Cupola
(B) Reheating furnace
(C) Glass tank furnace
(D) None of these
Answer: Option A
18. The thermal efficiency of an air/fuel gas preheating recuperator may be as high as __________ percent.
(A) 50
(B) 65
(C) 85
(D) 99
Answer: Option C
19. Which of the following is not a continuous waste heat recovery equipment from the flue gases going out of furnace?
(A) Economiser
(B) Regenerator
(C) Ceramic recuperator
(D) Waste heat boiler
Answer: Option B
20. Which of the following is not a recuperative furnace?
(A) Soaking pit
(B) Reheating furnace
(C) Steam boiler
(D) Coke oven
Answer: Option D
21. Waste heat from the outgoing flue gases in a thermal power plant is recovered by a/an
(A) Economiser
(B) Steam superheater
(C) Air preheater
(D) All (A), (B) and (C)
Answer: Option D
22. An example of shaft furnace is the
(A) L.D. converter
(B) Glass melting tank
(C) Blast furnace
(D) Soaking pit
Answer: Option C
23. Use of pulverised coal in boilers provides
(A) Higher calorific value
(B) Better combustion
(C) Smokeless burning
(D) Less erosion on furnace wall
Answer: Option B
24. In salt bath furnace, heat is transferred to the charge mainly by
(A) Conduction
(B) Convection
(C) Radiation
(D) None of these
Answer: Option A
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)
Answer: Option C