A. Using oxygen enriched combustion air
B. Preheating the combustion air
C. Reducing the heat loss through furnace openings & doors
D. All A., B. and C.
Related Mcqs:
- Thickness of stock does not affect the fuel economy of furnaces, if the material to be heated is of__________________?
A. Low emissivity
B. High thermal conductivity
C. Both A. and B.
D. Neither A. nor B. - Pulverised fuel fired furnaces employ ______________ fuel firing?
A. Horizontal
B. Vertical
C. Tangential
D. All A., B. and C. - Higher furnace temperature cannot be achieved by use of a lean fuel gas in the furnace by_________________?
A. Increasing the draft in the furnace
B. Preheating the fuel gas
C. Oxygen enrichment of combustion air
D. Preheating the combustion air - Fuel economy in an industrial furnace operation cannot be achieved by the use of__________________?
A. Stoichiometric combustion air
B. Non-preheated combustion air
C. Combustion air not enriched with oxygen
D. Recuperators - Hearth furnaces are not used for____________________?
A. Roasting
B. Melting
C. Reheating
D. None of these - Shaft furnaces are used for_______________________?
A. Smelting
B. Calcining
C. Roasting
D. All A., B. and C. - Thermal efficiency of furnaces can be improved by____________________?
A. Waste heat recovery from flue gas
B. Minimising heat losses from furnace walls
C. Maintaining proper draught
D. All A., B. and C. - Means for giving direction to the circulation of gases in furnaces are_____________________?
A. Fans
B. Arrangement of heating stock in the furnaces
C. Location of outlet ports and heating & combustion devices
D. All A., B. and C. - Ingress of cold air in the furnaces through cracks, charging doors, openings etc ________________?
A. Reduces the flue gas temperature and makes the furnace atmosphere oxidising
B. Increases the load on the induced draft fan
C. Reduces the furnace draught
D. All A., B. and C. - Which of the following furnaces will have maximum thermal efficiency ?
A. Soaking pits
B. Walking beam reheating furnace
C. Boiler furnace
D. Rotary kilns
