1, In the past, the kiln speed is slower, generally only 0.5 ~ 075 / min, then gradually increased to 1.0 ~ 1.5r / min. Suspension preheater, especially after the appearance of the precalciner kiln, the kiln speed can reach about 3r / min due to the fact that the decomposition of carbonate in the kiln material has been basically completed in the kiln.
2, Rotary kiln refers to rotary calcined kiln (commonly known as rotary kiln), belonging to the class of building materials equipment. Rotary kiln according to the different materials can be divided into cement kilns, metallurgical chemical kilns and lime kiln. Cement kiln is mainly used for calcining cement clinker, sub-dry production of cement kiln and wet production of cement kiln two categories. Metallurgical chemical kiln is mainly used for the metallurgical industry iron and steel plant magnetite roasted iron ore; chromium, nickel iron oxide roasting; refractory plant roasting high alumina bauxite and aluminum roasting clinker, aluminum hydroxide; chemical plant roasting chromium ore And chrome ore and other minerals. Lime kilns (ie, active lime kilns) are used to roast active lime and light-burned dolomites for steel mills and ferroalloy plants.