煆焼

Calcination is a chemical process that involves heating a substance to high temperatures in the supply of air or oxygen. This thermal treatment causes the decomposition or transformation of the material, often leading to the removal of volatile components, water, or other impurities. Calcination is commonly used in various industries, such as metallurgy, ceramics, cement production, and the chemical industry.

Some substances undergo chemical changes during calcination, decomposing into simpler or more stable compounds. For example, certain metal carbonates decompose into metal oxides and carbon dioxide upon calcination. Calcination can change the physical and chemical properties of the material, leading to the formation of new crystal structures or phases.

One of the most well-known examples of calcination is the conversion of limestone (calcium carbonate) into quicklime (calcium oxide) by heating it at high temperatures:

CaCO₃ (limestone) → CaO (quicklime) + CO₂ (carbon dioxide) > 900°C

Calcination is an essential step in many industrial processes, contributing to the production of various materials, chemicals, and products at temperatures up to 1500°C.