Powdery/granular solids drying

In view of the fact that most materials needing to be dried are powdery or granular solids, the development of the circulative impinging stream dryer is aimed at this kind of material. 

Wet feed enters the dryer at the upper end of the shell and tumbles around the steam tubes and dries. Gentle airflow (generally countercurrent to solids flow) is normally applied to the drying chamber to carry away the evaporated moisture. This type of dryer is used for continuous drying or heating of granular or powdery solids, which cannot be exposed to ordinary atmospheric or combustion gases. It is especially... 

When drying gas flows through a solid bed of granular, or powdery, or short fibrous product, it behaves like a liquid (fluidized... 

Solids which ordinarily can be dried on trays, such as powdery and granular materials, heavy sludges and pastes, beads and crystalline solids, can be continuously dried in a turbo-type drier, a form of direct drier. The simplest of these is shown in Fig. 12.18, The drier is fitted with a series of annular trays arranged in... 

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