A. Increases
B. Decreases
C. Remain same
D. Either A. or B., depends on other factors
Related Mcqs:
- As the C/H ratio of the fuel increases, the amount of CO2 formed on combustion _______________ for the same percentage of excess air?
A. Decreases
B. Increases
C. Remain same
D. May increase or decrease depending on the type of fuel - The calorific value of a gas of composition CO2 = 20%, H2 = 50%, CH4 = 30%, is y. If the composition of gas is changed to H2 = 50%, CH4 = 30%, CO2 = 10%, N2 = 10%, then the calorific value will be___________________?
A. y
B. 0.95 y
C. 1.05 y
D. 1.8 y - 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 - 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 - 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 - 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 - 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 - A carbonaceous fuel (containing no H2 or hydrocarbons) is burnt and the resulting flue gas contains 21% CO2. It means that___________________?
A. 21% excess air has been used for combustion
B. 21% excess oxygen has been used for combustion
C. Complete combustion of fuel has taken place
D. No excess air has been used for combustion - The maximum percentage of CO2 in a flue gas (from a carbonaceous fuel) can be_________________?
A. 21
B. 77
C. 79
D. 29 - Which of the following will generate maximum volume of product of complete combustion (Nm3/Nm3 of fuel) ?
A. Carburetted water gas
B. Blast furnace gas
C. Natural gas
D. Producers’ gas
