A. Temperature
B. Time
C. Nature of atmosphere
D. All A., B. and C.
Related Mcqs:
- Scaling of furnace stock is reduced by _______________ in flue gas?
A. CO
B. H2
C. High CO/CO2
D. All A., B. & 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. - 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. - Heat transfer rate to the stock/charge in the furnace does not depend upon the________________?
A. Emissivity of the refractory walls
B. Size of the furnace
C. Use of waste heat recovery equipments
D. Thickness of the stock - 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 - The heating capacity of muffle furnace depends on the_________________?
A. Surface area & emissivity of the stock
B. Properties of the muffle wall (temperature, area, and emissivity)
C. Both A. & B.
D. Neither A. nor B. - 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 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. - Size of the combustion chamber of a furnace depends upon the ___________________?
A. Heat release rate of the fuel
B. Preheat temperature of fuel & air
C. Method of mixing the fuel & air
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