Rotary cooler - direct or indirect
The rotary cooler is very often used for treating materials downstream of a pyroprocessing process.
In direct-mode, the material is cooled by ambient air passing through the rotary cooler. The heated up exit air from the cooler can be utilised, e.g. as secondary air for a kiln burner. It is also possible to reduce the material temperature very rapidly and effectively by injecting water. A water quantity control system ensures that just the right amount of water is injected to achieve the cooling effect. A combination of the two cooling media is also possible.
In indirect-mode, the material is usually cooled by water being sprayed onto the rotary cooler shell, so that the material being cooled does not come into contact with the cooling medium.
Normally the rotary dryer has two bearing assemblies and welded-on slide rings. It is usually equipped with a chain drive (wrap around), but for high capacities other solutions can also be used, such as floating tyres, girth gear and pinion drive etc..