A. Emissivity of the refractory walls
B. Size of the furnace
C. Use of waste heat recovery equipments
D. Thickness of the stock
Related Mcqs:
- Heat transfer rate to the charge/stock in a furnace does not depend upon the________________?
A. Type of fuels viz. solid, liquid or gaseous
B. Flue gas temperature
C. Emissivity of refractory walls
D. Initial temperature of the charged stock - In a furnace, the heat taken by the charge/stock and the heat lost to the furnace structure & flue gases depends on the__________________?
A. Rate of firing and emissivity of flame
B. Thermal conductivity of the charge & structural materials of furnace
C. Nature of process; whether batch, continuous or intermittent
D. All A., B. and C. - Ceramic coating material for furnace refractory, which increases its emissivity and thus the radiation heat transfer rate in the furnace, comprises of_________________?
A. Graphite powder
B. Thoria
C. Zircon powder
D. Beryllium - An electric furnace producing heat by means of an electric arc struck between each of three electrodes and the charge is called ____________ furnace?
A. Resistance
B. Arc
C. Low frequency induction
D. None of these - The rate of scaling of furnace stock depends upon the_________________?
A. Temperature
B. Time
C. Nature of atmosphere
D. All A., B. and C. - Design of waste heat boiler for recovery of waste heat from furnace gases depends upon the_________________?
A. Quantity & temperature of waste gas
B. Dust concentration & nature of dust in waste gas
C. Corrosive nature of the waste gas
D. All A., B. and C. - The amount of combustible escaping unconsumed from the furnace, depends upon the________________?
A. Air supplied and furnace temperature
B. Burner design (thoroughness of mixing versus stratification)
C. Air preheat and the flow of gases in the furnace (mixing by induction, by acceleration or by
change of direction)
D. All A., B. and C. - 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 - Rate of heat release in a furnace, which is the measure of heat intensity, is defined as_________________?
A. kcal/hr/m3 combustion space
B. kcal/m3 combustion space
C. kcal/hr
D. None of these - In salt bath furnace, heat is transferred to the charge mainly by __________________?
A. Conduction
B. Convection
C. Radiation
D. None of these
