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Chemical Engineering :: Fuels and Combustion

  1. In low temperature carbonisation of coal, the

  2. A.
    yield of coke oven gas is 290 Nm3 /ton dry coal.
    B.
    volatile matter in coke is zero.
    C.
    temperature maintained is 700°C.
    D.
    yield of tar is about 3% of dry coal.

  3. Low temperature oxidation and spontaneous combustion of freshly mined coal is accentuated, if

  4. A.
    it contains large amount of volatile matter.
    B.
    it is stored in tall heaps.
    C.
    smaller fines are stored in large quantity.
    D.
    all (a), (b) and (c).

  5. Coking time in narrow by-product coke ovens is around __________ hours.

  6. A.
    18
    B.
    48
    C.
    8
    D.
    80

  7. Blast furnace gas is a very poisonous gas because of its predominantly high __________ content.

  8. A.
    H2O
    B.
    CO2
    C.
    CO
    D.
    CH4

  9. Which of the following is a lean fuel gas ?

  10. A.
    Coke oven gas
    B.
    LPG
    C.
    Blast furnace gas
    D.
    Natural gas

  11. Which of the following fuel gases will require maximum amount of air for combustion of 1 Nm3 gas ?

  12. A.
    Blast furnace gas
    B.
    Natural gas
    C.
    Producer gas
    D.
    Water gas

  13. High rate of heating of coke ovens

  14. A.
    may damage its walls due to abrupt excessive swelling of coal.
    B.
    produces larger size coke.
    C.
    increases the time of carbonisation.
    D.
    none of these.

  15. A certain thickness of the coal, if stored unscientifically on soft (katcha) ground having no metallic/concrete flooring gets sunked into the ground, which is termed as the 'carpet loss'. The carpet loss may be of the order of __________ cms.

  16. A.
    1 to 2
    B.
    3 to 4
    C.
    5 to 15
    D.
    20 to 40

  17. Coalification means the

  18. A.
    process of conversion of lignite into anthracite.
    B.
    underground gasification of coal.
    C.
    complete combustion of coal.
    D.
    direct hydrogenation of coal.

  19. Hard coke is manufactured from

  20. A.
    lignite
    B.
    bituminous coal
    C.
    semi-anthracite
    D.
    anthracite