A dryer is provided with interacting heat transfer stator and rotor for improved processing capability. The stator comprises a stationary row of planar heat exchange banks supported within the vessel of the dryer. The rotor has a complemental number of annular heat exchange vanes interleaved between the heat exchange banks of the stator to create desired low-level agitation of the processed material as the rotor turns and to provide increased heat transfer efficiency. The vanes on the rotor and the banks of the stator each comprise an open grillwork of tubular members whereby the processed material may flow freely through the vanes and banks for additionally increased heat transfer efficiency and reduced residence time for the material.
