Volumetric ratio of N2 to O2 in dry atmospheric air is ______________?
A. 0.21
B. 3.76
C. 4.76
D. 0.79
Fuels and Combustion
Bituminous coal___________________?
Bituminous coal___________________?
A. Ignites less easily than anthracite
B. Is generally coking
C. Burns with smoky yellow flame
D. Both B. and C.
Washing of coal _________________?
Washing of coal _________________?
A. Reduces its ash & sulphur content
B. Improves its coking properties
C. Increase the fusion point of its ash by removing chlorine compounds
D. All A., B. and C.
Coalification means the ___________________?
Coalification means the ___________________?
A. Process of conversion of lignite into anthracite
B. Underground gasification of coal
C. Complete combustion of coal
D. Direct hydrogenation of coal
The ratio of % total carbon obtained in the ultimate analysis of coke and % fixed carbon obtained in the proximate analysis is always ___________________?
The ratio of % total carbon obtained in the ultimate analysis of coke and % fixed carbon obtained in the proximate analysis is always ___________________?
A. 1
B. < 1
C. > 1
D. Unpredictable
Low temperature oxidation and spontaneous combustion of freshly mined coal is accentuated, if __________________?
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.
If the specific heat of gaseous products of combustion of a fuel is high, the abiabatic flame temperature will be_____________?
If the specific heat of gaseous products of combustion of a fuel is high, the abiabatic flame temperature will be_____________?
A. Low
B. High
C. Very high, if the fuel is of low calorific value
D. None of these
The main advantage of forced draft over natural draft is that____________________?
The main advantage of forced draft over natural draft is that____________________?
A. Combustion of fuel is complete
B. Smaller height chimney can be used
C. Furnace control is easier
D. All A., B. & C.
Oxygen percentage (by weight) in atmospheric air is_________________?
Oxygen percentage (by weight) in atmospheric air is_________________?
A. 19
B. 21
C. 23
D. 29
Gasification of the solid fuel converts its organic part into combustible by interaction with air/oxygen and steam so as to obtain a secondary gaseous fuel of high calorific value having no ash. Gasification reactions are normally carried out at about _____________ °C?
Gasification of the solid fuel converts its organic part into combustible by interaction with air/oxygen and steam so as to obtain a secondary gaseous fuel of high calorific value having no ash. Gasification reactions are normally carried out at about _____________ °C?
A. 400-500
B. 900-1000
C. 1400-1500
D. 1700-1800