A. Reduces its thermal efficiency
B. Is indicated by flame sting out
C. Increases the flue gas temperature
D. None of these
Related Mcqs:
- Combustion of furnace oil in a furnace (soaking pit) with preheated combustion air at 400°C results in saving of about __________ percent furnace oil as compared to its combustion with atmospheric air, if the flue gas outlet temperature from the soaking pit is 1200°C ?
A. 5
B. 60
C. 20
D. 40 - The thermal efficiency of an air/fuel gas preheating recuperator may be as high as _____________ percent?
A. 50
B. 65
C. 85
D. 99 - Combustion of fuel in a furnace with oxygen enriched air results in higher__________________?
A. Flue gas volume
B. Flame temperature
C. Fuel consumption
D. Stack loss - Ceramic recuperators (made of SiC) is economical, only when used for preheating combustion air above _____________ °C?
A. 250
B. 650
C. 850
D. 1000 - In producer gas making furnace, steam is added along with air to mainly control the____________________?
A. Fusion of coal ash & clinker formation
B. C. V. of producer gas
C. Temperature of producer gas
D. Tar content in producer gas - Thermal efficiency of blast furnace stoves used for heating blast (air) may be about _____________ percent?
A. 20
B. 40
C. 60
D. 80 - Advantages of use of preheated combustion air are__________________?
A. Saving in fuel consumption
B. Reduction in scale losses
C. Increase in flame temperature
D. All A., B. and C. - Which of the following advantages is not associated with the use of preheated air for combustion of a fuel in the furnace ?
A. Increase in calorific value of the fuel
B. Increase in flame temperature
C. Reduction in scale losses
D. Saving in fuel consumption - In case of pulverised coal fired steam boiler, the secondary air serves the main purpose of_________________?
A. Transportation of coal
B. Drying of coal
C. Combustion of coal by supplying it around the burner
D. Preheating the primary air - If fuel and air are mixed ahead of the burner, it is called a/an ______________ burner?
A. Premix
B. Outside mixing type
C. Rotary
D. Diffusion
