Lime calcining is the conversion of limestone (CaCO3) to lime (CaO).
Limestone is a sedimentary rock, the third most abundant mineral. Limestone is mostly quarried above ground; however, some underground limestone mining is done. Limestone is found with many different characteristics and different impurities. The limestone characteristics change from different parts of the world and even different depths of mining. These characteristic differences are largely due to how it was formed. Limestone can be formed by chemically, organically, or clastic formation. Common impurities that can become a problem depending on the use or application are: SiO2 (Silica), Al2O3 (aluminum oxide), Fe2O3 (iron oxide). Limestone and it’s products are used in agriculture, soil stabilization, building, chemical and industrial purposes such as cement, steel, and alumina production; water purification and as an alkali for many mineral and chemical processes.
Normally a complete limestone evaluation is done at the Metso laboratory.
Even thought the chemical reaction is the same, the technologies are drastically different. The photos above show the different plant layouts.