A. All tar is evolved at 700°C
C. Hard semi-coke starts shrinking at 600°C
D. All A., B. and C.
Related Mcqs:
- In low temperature carbonisation (as compared to high temperature carbonisation) of coal__________________?
A. Ammonia yield is more
B. Aliphatic tar is produced
C. Free carbon in tar is more
D. All A., B. and C. - 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 (as compared to low temperature carbonisation) of coal___________________?
A. Coke oven gas yield is more
B. Tar yield is less but free carbon in tar is more
C. Calorific value of coke oven gas is less
D. All A., B. and C. - 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 low temperature carbonisation of coal as compared to high temperature carbonisation _____________ produced is less?
A. Difference in gross & net calorific value of the coke oven gas
B. Free carbon content in tar
C. Yield percentage of coke
D. Yield of ammonia present in coke oven gas - 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 - Presence of phosphorous in metallurgical coal__________________?
A. Is not undesirable
B. Reduces its calorific value
C. Badly affects the quality of steel
D. Increases its caking power - Cannel coal__________________?
A. Is non-coking
B. Has a high volatile matter content and burns with a luminous smoky flame
C. Is a non-banded coal which can be ignited easily with a match stick or candle flame, hence is
so named
D. All A., B. and C. - Sulphur in metallurgical coal__________________?
A. Contributes to its heating value
B. Affects the quality of steel produced as cracks develop on the surface while rolling the steel
C. Both A. and B.
D. Neither A. nor B. - Bright coal__________________?
A. Contains more than 90% durain
B. Contains more than 90% fussain
C. Contains mainly vitrain & clarain and is generally coking
D. Is non-coking
