Presence of nitrogen in combustion air does not reduce the ____________________?

Related Mcqs:

1. 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

2. 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

3. Which of the following is not increased by using preheated combustion air in place of ordinary air at room temperature ?

   A. Calorific value of the fuel
   B. Flame temperature achieved
   C. Speed of combustion of fuel
   D. Heat transfer rate to the stock in the furnace

4. Furnace oil consumption in a furnace for a given duty employing preheated combination air (at 300°) may be reduced by about ______________ percent as compared to the use of atmospheric combustion air?

   A. 5
   B. 10
   C. 20
   D. 35

5. 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

6. 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

7. Advantages of fluidised bed combustion are ____________________?

   A. Reduced NOx formation in flue gas
   B. Lower furnace operating temperature
   C. High heat transfer rate
   D. All A., B. & C.

8. The internal energy of the combustion products is ____________________ compared to that of reactants?

   A. More
   B. Less
   C. Equal
   D. More or less; (depends on the state of fuel.)

9. Air/gas ratio for complete combustion will be the highest for__________________?

   A. LPG
   B. Gobar gas
   C. Coke oven gas
   D. Carburetted water gas

10. About _____________ Nm3 of air will be required for the complete combustion of 2Nm3 of CO?

    A. 2
    B. 3
    C. 4
    D. 5