Quicklime Raw Materials

In actual production, to accelerate decomposition, the calcination temperature is often increased to 1000–1100℃. Due to the large size of the limestone raw materials or uneven temperature distribution in the kiln during calcination, quicklime often contains underburned and overburned lime. Underburned lime contains incompletely decomposed calcium carbonate, resulting in a lack of binding force during use. Overburned lime has a dense structure, often coated with a layer of molten material, and melts very slowly. Because the raw materials often contain magnesium carbonate (MgCO3), quicklime also contains magnesium oxide (MgO) as a minor component. Based on the amount of magnesium oxide, quicklime is classified into calcareous lime (MgO ≤ 5%) and magnesian lime (MgO > 5%).