The lowest temperature, at which a solid fuel produces enough vapors to support continuous combustion, is called ?

Related Mcqs:

1. For the case of a fuel gas undergoing combustion with air, if the air/fuel ratio is increased, the adiabatic flame temperature will_____________________?

   A. Increase
   B. Decrease
   C. Increase or decrease depending on the fuel type
   D. Not change

2. Higher efficiency in the combustion of solid fuel cannot be achieved by________________?

   A. Proper fuel preparation
   B. Keeping the flue gas exhaust temperature very high
   C. Adopting efficient-fuel firing technique & equipment
   D. Supplying correct quantity of combustion air

3. Theoretical flame temperature of a fuel is that temperature which is attained, when the fuel is completely burnt ‘using theoretical amount of air in___________________?

   A. Air
   B. Oxygen
   C. Either A. or B.
   D. Either A. or B. without gain or loss of heat

4. 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

5. 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

6. Use of excess of combustion air in the combustion of fuels results in__________________?

   A. Heat losses
   B. Long flame
   C. Condensation of water vapour from the fuel gas
   D. None of these

7. Deficiency of combustion air during combustion of a gaseous fuel_____________________?

   A. Lengthens the flame
   B. Causes heat loss of fuel by its partial combustion
   C. Both A. & B.
   D. Shortens the flame

8. Short/intense flame is produced during combustion of gaseous fuel by using________________?

   A. High amount/current of combustion air
   B. Low amount/current of combustion air
   C. Preheated secondary air
   D. Very little excess air

9. Flue gas obtained on complete combustion of pure acetylene (a hydrocarbon fuel) will contain __________________?

   A. CO
   B. CO2
   C. H2O
   D. Both B. & C.

10. As the C/H ratio of the fuel increases, the amount of CO2 formed on combustion _______________ for the same percentage of excess air?

    A. Decreases
    B. Increases
    C. Remain same
    D. May increase or decrease depending on the type of fuel