A. keep the burner tips cool
B. aid in proper combustion
C. cause sputtering, possibly extinguish¬ing flame
D. clean the nozzles
E. reduce flame length
A. provide air around burners for obtaining optimum combustion
B. transport and dry the coal
C. convert CO (formed in lower zone of furnace) into C02 at higher zone
D. air-delivered by forced draft fan
E. none ot the above
A. 21%
B. 23%
D. 30%
D. 40%
E. 70%
A. increase thermal efficiency of boiler
B. economise on fuel
C. extract heat from the exhaust flue gases
D. increase flue gas temperature
E. to heat feed water by bled steam
A. correct fuel air ratio
B. proper ignition temperature
C. 02 to support combustion
D. all the three above
E. none of the above
A. Higher calorific value at constant volume
B. Lower calorific value at constant volume ,
C. Higher calorific value at constant pressure
D. Lower calorific value at constant pressure
E. None of the above
A. carbon, hydrogen, nitrogen, sulphur, moisture
B. fixed carbon, ash, volatile matter, moisture
C. higher calorific value
D. lower calorific value
E. rough analysis
A. entropy
B. enthaply
C. pressure
D. temperature
E. all of the above
A. desirable
B. economical
C. essential
D. optional
E. uneconomical
A. boiler drum
B. superheater tubes
C. economiser
D. a separate coil
E. a separate coil located in convection path