ABSTRACT OF THE DISCLOSUREStructure is provided defining a flow path for granular materialsto be dried and laterally through which drying air may be passed. The flowpath includes inlet and outlet end portions and supply means is provided forsupplying granular material to the inlet end portion and discharge means isprovided for discharging granular material from the outlet end portion. Airpassage structure is provided including means for passing heated drying airlaterally through the inlet end portion of the flow path and cooled dryingair laterally through the outlet end portion of the flow path. The airpassage structure includes a substantially closed loop circuit and pumpstructure for pumping air through the circuit. Also, the air passage struc-ture includes heating structure for heating the drying air immediately priorto its passage laterally through the inlet end portion of the flow path andcooling structure for cooling and dehumidifying the drying air after itspassage laterally through the inlet end portion of the flow path and prior toits passage laterally through the outlet end portion of the flow path. Stillfurther, the air passage structure includes bypass structure operative tocause variable amounts of the drying air within the circuit to bypass theoutlet end portion of the material flow path. Further, structure is providedto obtain and maintain sub-atmospheric pressure in the drying chamber.
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