A coal with high _____________ content, would ignite most easily?

Related Mcqs:

1. Calorific value of coal middling generated in coal washeries during washing of coal may be around _____________ Kcal/kg?

   A. 1000
   B. 4000
   C. 6000
   D. 8000

2. Mineral matter content (M) and ash content A. in coal are approximately related as _______________?

   A. M = 1.1A
   B. M = A
   C. M = 1.5A
   D. M = 2A

3. Which will have the least volatile matter and hence will be the most difficult to ignite ?

   A. Bituminous coal
   B. Coke
   C. Semi-bituminous coal
   D. Anthracite

4. A coal having high volatile matter content will ________________?

   A. Give less yield of tar and gas on carbonisation
   B. Burn with a small non-smoky flame
   C. Have a very high calorific value
   D. None of these

5. A coal with high ash content is undesirable, as________________?

   A. It is abrasive to the coal pulveriser (i.e. ball mill) and the combustion chamber
   B. The ash in molten condition gets absorbed in the pores of the refractory lining of the furnace
   and causes its spalling due to different co-efficient of expansion/contraction of the refractory
   and the ash
   C. The ash retains the sulphur & phosphorus and thus affects the quality of products in
   metallurgical furnace apart from increasing the slag volume. Besides, it may fuse and stick to
   the boiler tubes thereby reducing the heat transfer
   D. All A., B. and C.

6. A good coking coal should have high ______________ content?

   A. Ash
   B. Sulphur & phosphorus
   C. Moisture
   D. None of these

7. A coal having high ratio of volatile matter to fixed carbon as compared to a coal having low ratio of volatile matter to fixed carbon _________________?

   A. Is less liable to spontaneous combustion on storage
   B. Is more difficult to ignite and produces a shorter flame
   C. Requires smaller combustion space and less secondary air
   D. None of these

8. A coal containing very high percentage of durain is called ______________ coal?

   A. Bright
   B. Splint
   C. Non-banded
   D. Boghead

9. Volatile matter content in coking coal may be about _____________ percent?

   A. 1
   B. 7
   C. 22
   D. 46

10. Ash content in the coke produced from a coking coal having 20% ash may be around _____________ percent?

    A. 6
    B. 12
    C. 18
    D. 24