A. Decreases the dew point
B. Increases the dew point
C. Reduces the combustion efficiency by limiting the permissible temperature reduction
D. Both B. and C.
Related Mcqs:
- 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 - Incomplete combustion of fuel in the furnace is judged by high _____________ of the flue gases?
A. CO content
B. Dew point
C. CO2 content
D. O2 content - If oxygen content in the flue gas rises too high, fuel is being wasted by _______________?
A. Incomplete combustion
B. Dry gas/stack gas loss
C. Moisture loss
D. None of these - Incomplete combustion of a fuel is characterised by the high _______________ in the flue gas?
A. Smoke
B. Temperature
C. Oxygen
D. Carbon monoxide - For which pair of the fuel gases, calorific value (C.V.) of one fuel is almost double that of the other on volume basis (i.e., kcal/Nm3), while the C.V. is same on weight basis (i.e., kcal/kg) ?
A. Propane and acetylene
B. Propane and LPG
C. Sewage gas and gobar gas
D. B.F. gas and coke oven gas - Oxygen content in a flue gas was found to be 4%. It implies that excess air used for combustion was around ______________ percent?
A. 4
B. 96
C. 20
D. 40 - Efficiency of the combustion of a fuel is judged by the ______________ the flue gas?
A. % of CO2 in
B. % of O2in
C. Temperature of
D. Colour of - 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 - 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 - With increase in C/H ratio of a fuel, the dew point of flue gases______________________?
A. Increases
B. Decreases
C. Remain same
D. May increase or decrease; depends on the type of fuel
