Method of maintaining fires in furnace during standby periods without undue consumption of fuel is called_________________?

Related Mcqs:

1. 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

2. For every 10% increase in the excess air; the fuel consumption increases by _______________ percent?

   A. 0.1
   B. 0.2
   C. 0.5
   D. 1.0

3. Fuel consumption in coke making can be reduced by___________________?

   A. Preheating, blending and de-ashing the coal
   B. Stamped charging of coal
   C. Dry quenching of coke
   D. All A., B. and C.

4. Correct viscosity of furnace oil at the burner tip for proper atomisation is about 25 centistokes. To reduce the viscosity of high viscosity furnace oil (250 centistokes) to the correct atomisation viscosity (i.e. 25 cst), it should be preheated to about ______________°C?

   A. 70
   B. 85
   C. 105
   D. 145

5. Explosion limit of blast furnace gas is 37 to 71% gas in gas-air mixture. It means that the blast furnace gas will explode when burnt in a confined space, if its concentration in the gas-air mixture is _______________ percent?

   A. 71%
   C. In between 37 & 71%
   D. None of these

6. Pitch creosote mixture (PCM) as compared to furnace oil is a better fuel, because its ___________________?

   A. Emissivity factor is higher
   B. Sulphur content is lower
   C. Flue gas has lower dew point thereby facilitating more waste heat recovery
   D. All A., B. and C.

7. Tar is a better fuel than furnace oil, because of its___________________?

   A. Higher calorific value
   B. Lower sulphur content
   C. Higher emissivity (0.8-0.9) resulting in higher radiation heat transfer rate
   D. Both A. and B.

8. White flue gas (resembling steam) coming out of the chimney of a thermal power plant indicates that the fuel used in the boiler furnace is_________________?

   A. Tar
   B. Coke oven gas
   C. Pitch
   D. Pulverised coke

9. Coke oven gas is a better fuel than blast furnace gas, because of its higher________________?

   A. Calorific value, cleanliness and relatively low distribution cost (due to its low specific gravity)
   B. Adiabatic flame temperature
   C. Heat release rate (thus requiring smaller combustion chamber)
   D. All A., B. and C.

10. White flue gas (resembling steam) coming out of the chimney of a thermal power plant indicates that the fuel used in the boiler furnace is_______?

    A. Tar
    B. Sulphide Coke
    C. Coke Oven Gas
    D. Pulverised coke

    Submitted by: Muhammad Mutsadiq Umer