2331. Heat balance of furnace provides means of determining the
Thermal efficiency of the process
Sources of heat losses
Scope of reduction of heat losses
All of the above
✅ The correct answer is option D.
2336. __________ is an indirectly heated furnace.
Open hearth furnace
Muffle furnace
Soaking pit
Reheating furnace
✅ The correct answer is option B.
2265. The rate of scaling of furnace stock depends upon the
Temperature
Time
Nature of atmosphere
All of the above
✅ The correct answer is option D.
2245. In a furnace, the heat taken by the charge/stock and the heat lost to the furnace structure & flue gases depends on the
Rate of firing and emissivity of flame
Thermal conductivity of the charge & structural materials of furnace
Nature of process ; whether batch, continuous or intermittant
All of the above
✅ The correct answer is option D.
2251. Low stack loss indicates the
Use of sub-stoichiometric air for combustion
Efficient use of fuel
Inefficient use of fuel
Oxygen enrichment of combustion air
✅ The correct answer is option B.
2256. Which is a continuous furnace?
Coke ovens
Annealing furnace
Glass tank furnace
None of these
✅ The correct answer is option C.
2222. Ceramic recuperators (made of SiC) is economical, only when used for preheating combustion air above __________ °C.
250
650
850
1000
✅ The correct answer is option B.
2227. Thermal efficiency of an open hearth furnace may be about __________ percent.
5
20
50
80
✅ The correct answer is option B.
2235. 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.
5
60
20
40
✅ The correct answer is option C.
2238. In a furnace employing forced draught as compared to induced draught,
Air is sucked in, so air leaks are more and hence the furnace efficiency is reduced
The fan operates hot and hence blades are liable to corrosion and erosion
Positive pressure exists in the furnace
None of these
✅ The correct answer is option C.