In these type of Dryers, air and feed are introduced from opposite directions. Feed is introduced from the top and hot air is introduced from the bottom.Counter Current Dryers have better efficiency and output, but are not ideal for heat sensitive material. Typically, these type of Dryers are ideal for products like Soaps, Dyestuff, Detergents etc.
Here feed first comes in contact of warm at its lowest temperature and gradually gets exposed to the hotter air. Counter Current Dryers are more effective and have better thermal efficiency then that of a Co-current Spray Dryer.