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Building Materials - Engineering

Q1:

Pick up the correct statement from the following:

A The heating of a material to redness in contact with air, is known as calcination

B The property of lime by which it sets or hardens in damp places having no free circulation of air is called setting

C The product that remains after calcination of limestone, is called lime

D All the above.

ANS:D - All the above.

The IUPAC defines calcination as " heating to high temperatures in air or oxygen".

However, calcination is also used to mean a thermal treatment process in the absence or limited supply of air or oxygen applied to ores and other solid materials to bring about a thermal decomposition. A calciner is a steel cylinder that rotates inside a heated furnace and performs indirect high-temperature processing (550"1150 °C, or 1000"2100 °F) within a controlled atmosphere.