Rotary kiln is refer to rotate calcination kiln, belongs to construction material equipment. Rotary kiln can be divided into cement kiln, metallurgy chemical kiln and lime kiln according to different materials. Cement kiln is used for making of cement clinker and there are dry and wet methods to make cement. Metallurgy chemical kiln is used in metallurgy industry and ironworks for lean iron ore, chromium ore and ferronickel ore calcination.