Chemical Engineering - Refractory Technology

41. 

Cold crushing strength of ordinary fireclay brick is about 950 kg/cm2 . On exposure to a temperature of about 1500°C, its crushing strength may come down to as low as __________ kg/cm2 .

A. 450
B. 250
C. 150
D. 65

Answer: Option D

Explanation:

No answer description available for this question. Let us discuss.

42. 

Zirconia refractory

A. does not react with basic slags.
B. is produced from baddeleyite.
C. can not be used as an insulator.
D. has poor electrical conductivity at high temperature.

Answer: Option B

Explanation:

No answer description available for this question. Let us discuss.

43. 

Which one contains maximum percentage of Al2O3 ?

A. Firebrick
B. Sillimanite
C. Magnesite
D. Aluminous firebrick

Answer: Option B

Explanation:

No answer description available for this question. Let us discuss.

44. 

Which of the following does not occur during firing/burning of refractories ?

A. Removal of water of hydration.
B. Vitrification.
C. Decrease in crushing strength.
D. Development of stable mineral form.

Answer: Option C

Explanation:

No answer description available for this question. Let us discuss.

45. 

Silicon carbide refractories are used in the

A. muffle furnace
B. zinc smelting furnace
C. ceramic recuperators
D. all (a), (b) and (c)

Answer: Option D

Explanation:

No answer description available for this question. Let us discuss.