What is the process of manufacturing lime?
Lime, mainly composed of calcium oxide (CaO), is a vital material in construction, agriculture, and industry. The manufacturing process of lime primarily involves the calcination of limestone.
First, high - quality limestone, rich in calcium carbonate (CaCO₃), is selected and crushed into appropriate - sized lumps. This size control is crucial as it ensures uniform heating during the subsequent calcination process.
Next comes the calcination stage, which is the core of lime production. The crushed limestone is loaded into a lime kiln, such as a vertical lime kiln. Fuel, like coal or natural gas, is introduced to heat the kiln. As the temperature rises to around 900 - 1200°C, a chemical reaction occurs: calcium carbonate decomposes into calcium oxide (lime) and carbon dioxide (CO₂). The reaction equation is CaCO₃ → CaO + CO₂↑.
The newly formed lime, still extremely hot, is discharged from the bottom of the kiln. It then undergoes cooling to prevent spontaneous combustion and to make it safe for storage and transportation. Through these steps, limestone is transformed into useful lime, ready to serve various industrial and daily - life purposes.
