Calcium oxide, also known as quicklime, is manufactured industrially by the thermal decomposition of calcium carbonate (limestone) in a lime kiln.
The process typically involves the following steps:
Quarrying and crushing of limestone
Large deposits of limestone are quarried and crushed into smaller pieces. The size of the limestone pieces depends on the requirements of the lime kiln.
Calcination of limestone
The crushed limestone is then heated to a high temperature (around 900-1000°C) in a lime kiln. This process, known as calcination, causes the limestone to decompose into calcium oxide and carbon dioxide.
The calcium oxide produced in the lime kiln is then processed further to remove impurities and convert it into a usable product. This may involve crushing the quicklime into smaller pieces, hydrating it to produce calcium hydroxide, and then drying it to produce calcium oxide.
Packaging and transportation
The final product is packaged and transported to customers for use in various industrial applications, such as steelmaking, water treatment, and construction.
The production of calcium oxide is an energy-intensive process that requires a large amount of heat. Therefore, the cost of manufacturing quicklime is influenced by the cost of fuel and energy used in the process.