E-PolyLearning

1. Which of the following is the most suitable for preheating combustion air above 650°C ?
a. Regenerator
b. Metallic recuperator
c. Ceramic recuperator
d. None of these
View Answer Report Discuss 50-50!
Answer: (c).Ceramic recuperator

2. Soaking pits are meant for heating steel
a. ingots
b. coils
c. sheets
d. slabs
View Answer Report Discuss 50-50!
Answer: (a).ingots

3. The purpose of controlling the furnace atmosphere is to prevent surface attack by
a. oxidation/scaling
b. decarburising
c. sulphur penetration
d. either of the above
View Answer Report Discuss 50-50!
Answer: (d).either of the above

4. Thermal efficiency of a limestone calcination rotary kiln may be around __________ percent.
a. 20
b. 40
c. 65
d. 80
View Answer Report Discuss 50-50!
Answer: (b).40

5. In producer gas making furnace, steam is added along with air to mainly control the
a. fusion of coal ash & clinker formation.
b. C. V. of producer gas.
c. temperature of producer gas.
d. tar content in producer gas.
View Answer Report Discuss 50-50!
Answer: (a).fusion of coal ash & clinker formation.

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