Home / Chemical Engineering / Fuels and Combustion :: Section 2

Chemical Engineering :: Fuels and Combustion

  1. The calorific value of a gas of composition CO2 = 20%, H2 = 50%, CH4 = 30%, is y. If the composition of gas is changed to H2 = 50%, CH4 = 30%, CO2 = 10%, N2 = 10%, then the calorifice value will be

  2. A.
    y
    B.
    0.95 y
    C.
    1.05 y
    D.
    1.8 y

  3. For which pair of the fuel gases, calorific value (C.V.) of one fuel is almost double that of the other on volume basis (i.e., kcal/Nm3 ), while the C.V. is same on weight basis (i.e., kcal/kg) ?

  4. A.
    Propane and acetylene
    B.
    Propane and LPG
    C.
    Sewage gas and gobar gas
    D.
    B.F. gas and coke oven gas

  5. One kg of carbon for theoretically complete combustion requires __________ kg of air.

  6. A.
    11.5
    B.
    0.5
    C.
    23
    D.
    12

  7. If CO2 is not fully absorbed by the KOH solution meant for its absorption in the orsat apparatus, it will appear as

  8. A.
    O2
    B.
    CO
    C.
    N2
    D.
    SO2

  9. By-products are __________ recovered in 'Beehive ovens'.

  10. A.
    fully
    B.
    partially
    C.
    not at all
    D.
    negligibly

  11. Use of pulverised coal in boiler furnace provides

  12. A.
    high calorific value.
    B.
    better combustion.
    C.
    smokeless burning.
    D.
    less erosion on furnace walls.

  13. Deficiency of combustion air during combustion of a gaseous fuel

  14. A.
    lengthens the flame.
    B.
    causes heat loss of fuel by its partial combustion.
    C.
    both (a) & (b).
    D.
    shortens the flame.

  15. Froth floatation is used for

  16. A.
    washing fine coal dust (< 0.5 mm size).
    B.
    washing lump coal (> 80 mm size).
    C.
    removing ash from the coal based on difference in specific gravity of coal and ash.
    D.
    all (a), (b)and(c).

  17. (64-132) rank coal (ASTM) means a coal with 64%

  18. A.
    fixed carbon and having a heat value of 13, 200 BTU/1b.
    B.
    ash and a heating value of 13, 200 BTU/1b.
    C.
    fixed carbon and a heating value of 132 BTU/1b.
    D.
    none of these.

  19. The sequence of absorption in flue gas analysis by Orsat's apparatus is respectively

  20. A.
    CO2, O2, CO
    B.
    CO, O2, CO2
    C.
    CO2, CO, O2
    D.
    O2, CO2, CO