The Design of Rotary Kiln Type

The rotary kiln type means the diameter change of each barrel diameter section. According to the barrel formation, there are several rotary kiln types as follows:
(1) Heeven type: It is easy to manufacture and install. The speed of the moving material in the kiln is uniform. The operation is easy to control and the kiln body building and maintenance are convenient.

(2) Hot end broaden type: It increases the unit fuel amount and heat transfer amount. Expanding the hot end when the rotary kiln’s diameter is small can raise the output. It is applicable for drying the material with high calcinating temperature.

(3) Cold end broaden type: It is easy to install heat exchanger, enlarges the heating surface of the drying material, speeds up the water evaporation of the slurry, decreases the heat consumption and the fine dust loss and is applicable to deal with materials of large amount evaporation capacity and difficult drying property.

(4) Both ends broaden type (dumbbell): The central fill factor is high and the material flow chance decreases which can save the steels.

(5) Big belly kiln: It refers to the kiln enlarges the calcinating zone or the decomposition zone. This type of kiln is easy to hang kiln skin. When the capacity of the drying zone and the calcinating zone is enough, the output can be raised obviously while it is hard to operate.
In a word, whichever zone is enlarged, the balance between preheating capacity and calcinating capacity must be kept. The obvious effect can be achieved only when after the kiln production and full investigation (including the necessary thermotechnical measurement and calculation) are done and the weak link is found and enlarged.

For the development trends in land, the heeven type rotary kiln is favored, and the rotary kiln size is larger and larger. Other rotary kiln used in non-ferrous metal industry (reduction, volatilization, vulcanizing concentrate calcinating, chloridizing roasting, segregation, calcinating conversion) adopts the shorter heeven kiln.