Preheating of a gaseous fuel results in increased____________________?

Related Mcqs:

1. 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

2. A gaseous fuel in order to develop luminosity on burning, must contain __________________?

   A. Carbon monoxide
   B. Hydrocarbons
   C. Hydrogen
   D. Oxygen

3. 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

4. Presence of ______________ in a dry gaseous fuel does not contribute to its calorific value?

   A. Sulphur
   B. Oxygen
   C. Hydrogen
   D. Carbon

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. A liquid/gaseous fuel containing hydrocarbons and high amount of sulphur is burnt with 40% excess air. The flue gas still contains large amount of carbon monoxide. This may be due to the_________________?

   A. Presence of large quantity of hydrogen in the fuel
   B. Low calorific value of the fuel
   C. High sulphur content in the fuel
   D. Lack of thorough mixing of fuel with air

7. During combustion of a gaseous fuel, the presence of a non-luminous flame is an indication of the____________________?

   A. Incomplete combustion
   B. Complete combustion
   C. High oxygen in flue gas
   D. None of these

8. Optimum preheating temperature for pitch creosote mixture (PCM) which is also termed as C.T.F-200, before atomisation through burners is_________________?

   A. 200 °F
   B. 200 °C
   C. 200 °K
   D. 200 °R

9. Preheating of coal charge for the coke ovens reduces the __________________?

   A. Time of carbonisation
   B. Yield of gas and tar
   C. Fuel consumption in coking
   D. All A., B. and C.

10. Preheating of ______________ the flame temperature?

    A. The gaseous fuel before combustion decreases
    B. Combustion air decreases
    C. Either the fuel or the air or both, increases
    D. Either the fuel or the air does not affect