Cement clinker is made of limestone, clay and iron raw materials as the main raw materials. It is prepared into raw materials in an appropriate ratio, burned until partially or completely melted, and cooled to obtain semi-finished products. In the cement industry, the main chemical components of Portland cement clinker are calcium oxide, silica and a small amount of alumina and iron oxide. The main mineral composition is tricalcium silicate, dicalcium silicate, tricalcium aluminate and tetra calcium iron aluminate. Portland cement clinker and appropriate amount of gypsum are ground together to form Portland cement. Under normal circumstances, it is mainly composed of CaO.SiO2.Al2O3 and Fe2O3, the total content of which is usually above 95%.
