Fuels And Combustion Questions MCQs


fuels and combustion Questions

Total Questions : 498

Page 1 of 25 pages
Question 1. Incomplete combustion of fuel in the furnace is judged by high __________ of the flue gases.
  1.    CO content
  2.    Dew point
  3.    CO₂ content
  4.    O₂ content
Answer: Option A
Question 2. Fusion point of coal ash generally varies from 1000 to 1700° C. Ash having fusion point less than __________ °C is liable to form clinker.
  1.    1100
  2.    1250
  3.    1350
  4.    1400
Answer: Option A
Question 3. High sulphur content in a fuel __________ of the flue gases.
  1.    Decreases the dew point
  2.    Increases the dew point
  3.    Reduces the combustion efficiency by limiting the permissible temperature reduction
  4.    Both B & C
Answer: Option D
Question 4. Kopper-Totzek coal gasifier (installed in a coal based nitrogeneous fertiliser plant) employs a/an __________ bed gasifier.
  1.    Entrained
  2.    Moving
  3.    Fixed
  4.    Fluidised
Answer: Option A
Question 5. Coal tar fuel - 200 (CTF 200) is a mixture of
  1.    Pitch and creosote oil
  2.    Light oil and pitch
  3.    Anthracene and crecosote oil
  4.    Solar oil and pitch
Answer: Option A
Question 6. Which of the following combustibles is absent in blast furnace gas?
  1.    H₂
  2.    CH₄
  3.    CO
  4.    None of these
Answer: Option B
Question 7. Which of the following would require maximum amount of % excess air for complete combustion?
  1.    Coke oven gas
  2.    Furnace oil
  3.    Pulverised coal
  4.    Lump coal (fixed on chain grate)
Answer: Option D
Question 8. A sample of natural gas containing 80% methane (CH₄) and rest nitrogen (N₂) is burnt with 20% excess air. With 80% of the combustibles producing CO₂ and the reminder going to CO, the Orsat analysis in volume percent is
  1.    CO₂ : 6.26, CO : 1.56, O₂ : 3.91, H₂O :15.66, N₂ : 72.60
  2.    CO₂ : 7.42, CO : 1.86, O₂ : 4.64, N₂:86.02
  3.    CO₂ : 6.39, CO : 1.60, O₂ : 3.99, H₂O:25.96, N₂:72.06
  4.    CO₂ : 7.60, CO : 1.90, O₂ : 4.75, N₂ : 85.74
Answer: Option B
Question 9. Calorific value of gobar gas (containing CH₄ = 60% , H₂ = 10% ; CO₂ = 30%) may be about __________ Kcal/Nm³.
  1.    1800
  2.    3200
  3.    5400
  4.    10200
Answer: Option C
Question 10. Calorific value of coal middling generated in coal washeries during washing of coal may be around __________ Kcal/kg.
  1.    1000
  2.    4000
  3.    6000
  4.    8000
Answer: Option B
Question 11. Calorific value of dry wood may be around __________ Kcal/kg.
  1.    5
  2.    50
  3.    500
  4.    5000
Answer: Option A
Question 12. Calorific value of bituminous coal may be around __________ Kcal/kg.
  1.    500
  2.    1500
  3.    6500
  4.    20000
Answer: Option C
Question 13. Calorific value of a typical dry anthracite coal may be around __________ Kcal/kg.
  1.    1000
  2.    4000
  3.    8000
  4.    15000
Answer: Option C
Question 14. Ash content in the coke produced from a coking coal having 20% ash may be around __________ percent.
  1.    6
  2.    12
  3.    18
  4.    24
Answer: Option D
Question 15. Pick out the wrong statement.
  1.    Pulverised fuel can be completely burnt with less percentage of excess air compared to lump coal
  2.    Low grade coal can be used, but generally high volatile matter coals are more suitable for making pulverised fuel
  3.    Regulation of furnace temperature and atmosphere (oxidising or reducing) is easily possible with pulverised fuel firing
  4.    None of these
Answer: Option D
Question 16. Volatile matter content of metallurgical coke may be around __________ percent.
  1.    1-2
  2.    10-15
  3.    22-26
  4.    30-33
Answer: Option A
Question 17. Quantity of coke produced from metallurgical coal may be around __________ percent.
  1.    30
  2.    50
  3.    75
  4.    95
Answer: Option C
Question 18. Abrasion index of blast furnace coke should be around __________ percent.
  1.    20
  2.    35
  3.    55
  4.    80
Answer: Option D
Question 19. Natural draught produced by a chimney depends upon the
  1.    Density of the chimney gases
  2.    Height of the chimney
  3.    Both A & B
  4.    Neither A nor B
Answer: Option C
Question 20. Which of the following is not a binder for coal briquetting?
  1.    Coal tar
  2.    Bitumen
  3.    Molasses
  4.    None of these
Answer: Option D