Product Temperature and Vapour Removal

The gas inside the process area consists only of vapour from the present solvent. The vapours are removed from the solids because of a pressure difference to the 

Under these conditions the drying process is so called heat transfer controlled . 

For the removal of the vapours that accrue inside the capillaries a pressure gradient from inside the capillaries to the particle surface is necessary. This pressure gradient is developed by heating up the product to a temperature above the 

The drying capacity is no longer only depending on the heat transfer but also on diffusion processes inside the capillaries and so from the structure of the product itself. 

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