The process principle of burning limestone into lime
The main component of limestone is calcium carbonate (CaCO3), which is burned into lime. The core process principle is based on the decomposition reaction of calcium carbonate under high temperature conditions.
When limestone is placed in high-temperature equipment such as lime kilns, as the temperature continues to rise and reaches the decomposition temperature of calcium carbonate (about 900 ℃), calcium carbonate begins to decompose. The chemical reaction equation is: CaCO ∝ (high temperature)=CaO+CO ₂ ↑. In this reaction, calcium carbonate decomposes to produce calcium oxide (CaO, the main component of lime) and carbon dioxide gas. Carbon dioxide will escape from the lime kiln, while calcium oxide remains inside the kiln.
To ensure sufficient reaction, it is necessary to continuously provide sufficient heat to stabilize the temperature inside the kiln within a suitable range and ensure sufficient reaction time. At the same time, the particle size of limestone raw materials can also affect the reaction effect. Appropriate particle size can increase the reaction contact area and accelerate the reaction rate.
After high-temperature calcination, the obtained lime (calcium oxide) has strong alkalinity and is widely used in many fields such as construction, chemical industry, metallurgy, etc. It is an important basic industrial raw material.
