Rotary kiln refers to rotary calcination kiln, belonging to cement building materials equipment. It is widely used in ore beneficiation, metallurgy, building materials, chemicals, electricity, petroleum, coal, transportation, fertilizer, gas and other industries. Rotary kiln is mainly used for calcination of cement clinker, including dry and wet production cement kilns. Metallurgical chemical kiln is mainly used for the magnetization and calcination of lean iron ore in metallurgical industry, the oxidation and calcination of chromite and josephinite, etc.