Out of the following, which is the most important parameter for the blast furnace grade coke ?

Related Mcqs:

1. Explosion limit of blast furnace gas is 37 to 71% gas in gas-air mixture. It means that the blast furnace gas will explode when burnt in a confined space, if its concentration in the gas-air mixture is _______________ percent?

   A. 71%
   C. In between 37 & 71%
   D. None of these

2. Blast furnace gas compared to coke oven gas has_________________?

   A. Lower ignition temperature
   B. Narrower limit of inflammability
   C. Higher calorific value
   D. Lower theoretical flame temperature

3. Abrasion index of blast furnace coke should be around _____________ percent?

   A. 20
   B. 35
   C. 55
   D. 80

4. Caking index of coal blend used for blast furnace coke making is about_________________?

   A. 8
   B. 12
   C. 22
   D. 36

5. Blast furnace coke is made from coal by_____________________?

   A. Low temperature carbonisation
   B. High temperature carbonisation
   C. Medium temperature carbonisation
   D. Heating the coal in an oven in presence of air

6. Coke oven gas is a better fuel than blast furnace gas, because of its higher________________?

   A. Calorific value, cleanliness and relatively low distribution cost (due to its low specific gravity)
   B. Adiabatic flame temperature
   C. Heat release rate (thus requiring smaller combustion chamber)
   D. All A., B. and C.

7. Coke oven gas compared to blast furnace gas is________________?

   A. More explosive and inflammable
   B. Less poisonous
   C. Lighter
   D. All A., B. and C.

8. Higher percentage of ash in coal meant for the production of metallurgical grade coke ___________________?

   A. Decreases the hardness of coke
   B. Decreases the abrasion resistance of coke
   C. Causes brittleness in steel
   D. None of these

9. Critical Air Blast (CAB) value of coke is a direct measure of its__________________?

   A. Reactivity
   B. Hardness
   C. Strength
   D. None of these

10. Width of the coke oven towards coke side is slightly more than that on pusher side to____________________?

    A. Facilitate easy discharging of coke as it swells during carbonisation
    B. Facilitate uniform heating of the oven
    C. Increase the output of the coke
    D. None of these