A. Decreases with increase in surface area
B. Does not vary with increase in surface area
C. Is more for low volatile coal compared to high volatile coal
D. Is accelerated by storage in large heaps with small surface to volume ratio
Related Mcqs:
- Low temperature oxidation of coal resulting from bad storage conditions does not decrease its______________________?
A. Caking power
B. Calorific value
C. Hydrogen content
D. Oxygen content - Low temperature oxidation of coal during storage does not decrease its__________________?
A. Oxygen content
B. Caking power
C. Calorific value
D. None of these - To avoid fire by spontaneous combustion of coal due to its low temperature oxidation, it should be stored in___________________?
A. Shallow and small piles
B. Fine sizes without the presence of any lump
C. Closed space without any ventilation facility
D. Large heaps with small surface to volume ratio - Low temperature oxidation of stored coal results in the________________?
A. Decrease in its caking power & calorific value
B. Decrease in its carbon & hydrogen content
C. Increase in its oxygen content
D. All A., B. and A. - Low temperature oxidation and spontaneous combustion of freshly mined coal is accentuated, if __________________?
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. - Low temperature oxidation of coal is accelerated by the____________________?
A. Storage in large heaps
B. Storage in compressed piles
C. Absence of porous or friable particles
D. All A., B. and C. - Yield of coke oven gas in low temperature carbonisation of coal is about ______________ Nm3 /ton of dry coal?
A. 60
B. 160
C. 500
D. 750 - Coke oven gas produced by high temperature carbonisation of coal (as compared to that produced by low temperature carbonisation), has_________________?
A. Higher calorific value
B. Lower hydrogen content
C. Both A. and B.
D. Neither A. nor B. - In high temperature carbonisation of coal compared to low temperature carbonisation ?
A. Yield of ammonia is less
B. Aromatic content of tar is low
C. H2 content in the coke oven gas is more
D. Calorific value of the coke oven gas is lower - In high temperature carbonisation (as compared to low temperature carbonisation) of coal, the______________?
A. Gas yield is less
B. Tar yield is more
C. Ignition temperature of coke produced is less
D. Aromatic content of tar produced is more
