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.
Related Mcqs:
- Cannel coal and boghead coal are the examples of _________________?
A. Humic coals
B. Liptobiolites
C. Sapropelic coals
D. None of these - 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. - 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 - 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. - During the carbonisation of coal__________________?
A. All tar is evolved at 700°C
C. Hard semi-coke starts shrinking at 600°C
D. All A., B. and C. - 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 - Which of the following would require least amount of secondary air for combustion ?
A. Coke breeze containing 25% ash and 2% volatile matter
B. Anthracite containing 10% volatile matter and 8% ash
C. Bituminous coal containing 20% ash and 25% volatile matter
D. Semi-bituminous coal containing 25% ash and 20% volatile matter - Very ______________ coals are completely devoid of cokability i.e., it is non-coking ?
A. Young
B. Mature
C. Both A & B
D. Neither A nor B - In general, the limit of inflammability/explosion limit of fuel gases is widened by the__________________?
A. Increase in gas pressure
B. Increase in temperature (i.e. preheating)
C. Use of pure oxygen for combustion instead of air
D. All A., B. & C. - Calorific value of a typical dry anthracite coal may be around _____________ Kcal/kg?
A. 1000
B. 4000
C. 8000
D. 15000
