Dry air required to burn 1 kg of carbon completely may be around ______________ kg?

Related Mcqs:

1. Pure carbon is completely burnt in oxygen. The flue gas analysis is 70%CO2, 20%CO and 10%O2. The percent excess oxygen used is __________________?

   A. 20
   B. 12.5
   C. 0
   D. 10

2. Dry air requirement for burning 1 Nm3 of CO to CO2 may be around _______________ Nm3 ?

   A. 2.4
   B. 1.75
   C. 0.87
   D. 11.4

3. 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

4. Volumetric ratio of N2 to O2 in dry atmospheric air is ______________?

   A. 0.21
   B. 3.76
   C. 4.76
   D. 0.79

5. 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

6. Carbon Content by weight in air dried wood may be about _______________ percent?

   A. 10
   B. 25
   C. 50
   D. 80

7. Tar yield in the low temperature and high temperature carbonisation of dry coal may be respectively ______________ percent?

   A. 3 & 10
   B. 10 & 3
   C. 10 & 20
   D. 15 & 8

8. Quantity of coke oven gas produced by high temperature carbonisation of one ton of dry coal may be around ______________ Nm3?

   A. 30
   B. 300
   C. 3,000
   D. 30,000

9. Calorific value of dry wood may be around ______________ Kcal/kg?

   A. 5
   B. 50
   C. 500
   D. 5000

10. 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