2. Which furnace employs preheating, heating and soaking zones ?
3. Calcination of limestone to produce lime is done in a __________ kiln.
4. Thickness of stock does not affect the fuel economy of furnaces, if the material to be heated is of
5. Ceramic recuperators compared to metallic recuperators for the same duty
6. In order to maintain a reducing atmosphere in a furnace, it should have
7. Which is the most thermally efficient furnace ?
8. The heat recoverable from flue gases of furnaces depends on the
9. Ceramic recuperators (made of SiC) is economical, only when used for preheating combustion air above __________ °C.
10. Which is a continuous furnace ?
11. Which of the following is the most suitable for preheating combustion air above 650°C ?
12. Soaking pits are meant for heating steel
13. The purpose of controlling the furnace atmosphere is to prevent surface attack by
14. Thermal efficiency of a limestone calcination rotary kiln may be around __________ percent.
15. In producer gas making furnace, steam is added along with air to mainly control the
16. Fuel used in B.F. stove is
17. Tunnel kilns are usually used for
18. The thermal efficiency of a steel slab reheating furnace (walking beam type) may be about __________ percent.
19. Higher furnace temperature can not be achieved by use of a lean fuel gas in the furnace by
20. Temperature of a furnace fired with low calorific value fuel gas (i.e. lean gas) can be increased by
21. Ceramic coating material for furnace refractory, which increases its emissivity and thus the radiation heat transfer rate in the furnace, comprises of
22. In reverberatory furnace, charge is heated mainly by
23. An example of a periodic furnace is the
24. Ostwald charts are meant for
25. Maximum heat transfer in high temperature furnaces is by