Pressure drop and transfer rate of wood powder pellets were measured using a cold model of a horizontally rotating cylinder with two pairs of internal screw cylinders. The transfer rate was one order of magnitude smaller than that when the pellets are moved along by a screw movement, which indicates their flow over the central shaft of screw cylinders. Using internal cylinders of simple design, the operational range showing good gas-solid contact was narrow. Modification of the internal cylinders with partial cover of the entrance sides allowed high packing of pellets with good gas-solid contact and stable pressure drop.