Abstract: A single pass rotary dryer in which heated gas and a moist material is blown through a rotating drum. The drum has inwardly extending flights or vanes which deflect particles of the material back into the gas flow. A flight is oriented at an oblique angle to the longitudinal axis of the drum in order to present an ascending ramp to incoming material. There is a core oriented longitudinally in the drum. The core may be hollow and perforated with holes through which particles of material may pass. The core may have flights and a narrowing closed end facing the incoming material.