TSEE MCQ part 4

16. Air venting in a steam system is required because air is ___________.

a) A good conductor b) An insulator

c) Inert d) Diluent

Answer B

 

17. Furnace wall heat loss does not depend on

a) Temperatures of external wall surfaces b) Velocity of air around the furnace

c) Thermal conductivity of wall brick d) Material of stock to be heated

Answer D

 

18. In a CFBC boiler _________ are required to capture large recycled amount of bed material

a) Settling chambers b) Mechanical cyclones

c) Bag filters d) Scrubbers

Answer B

 

19. Example for basic type of refractory is

a) Chrome b) Chrome magnesite

c) Alumina d) All the above

Answer B

 

20. Which material is used to control SO2 emissions in FBC boilers

a) CaO b) Lime stone

c) Silica d) Sand

Answer B

 

21. The effectiveness of a heat exchanger does not depend on

a) Specific heat of hot fluid b) Specific heat of cold fluid

c) Inlet temperature of hot fluid d) LMTD

Answer D

 

22. Which of the following fuel needs maximum amount of excess air for complete

combustion?

a) Furnace oil b) Natural gas

c) Pulverised coal d) Wood

Answer D

 

23. In a coal fired boiler, which parameter influences flame profile the most?

a) Fixed carbon b) Volatile matter

c) Hydrogen d) All of the above

Answer B

 

24. Which one of the following boilers utilizes the combination of suspension and grate

firing?

a) Spreader stoker boiler b) Fluidized bed boiler

c) Traveling grate stoker boiler d) Pulverized fuel boiler

Answer A

 

25. In an oil fired steam boiler the Air to Fuel ratio by mass is 15:1 & evaporation ratio is

14:1. The flue gas to fuel ratio will be

a) 29:1 b) 16:1

c) 1:1 d) 15:1

Answer B

 

26. The maximum possible evaporation ratio of a boiler (From & At 100 ºC basis) fired with coal having a calorific value of 4050 kcal/kg and operating at 80 % efficiency will be

a) 5 b) 6

c) 7.5 d) 9.4

Answer B

 

28. Radiation losses from the surface of a boiler practically

a) Increase with increase in boiler loading

b) Decrease with increase in boiler loading

c) Are independent of boiler loading

d) Are dependent on boiler loading

Answer C

 

29. Desirable boiler water pH should be ?

a) 5 - 7 b) 7 - 9

c) 9 - 11 d) None of the above

Answer B

 

30. Soot deposition on boiler tubes is due to

a) Poor water treatment b) High moisture content in fuel

c) High excess air d) Incomplete combustion

Answer D