PURPOSE: To enable transport at a low speed and to prevent damage on granules by supplying a small amount of air having its speed less than the floating speed of the granules in a transport pipe in the middle of the pipe, and by repeatedly switching an sucked air capacity between the air capacity corresponding to a speed less than the floating speed and the air capacity corresponding to a speed more than that for a thieving columnar transport.

CONSTITUTION: First, a flow regulating valve 40 is almost opened, and the air capacity flowing in a transport pipe 10 is set extremely smaller than that corresponding to the floating speed. By this, granule 8 from a hopper 28 are retained at a vertical transport part and form a blocking layer. Next, the flow regulating valve 40 is closed to the intermediate position, and a small amount of air less than that corresponding to the floating speed is introduced from the middle of the transport pipe 10 through an electromagnetic valve 34 and an air supply part 36 so as to fluidize the blocking layer. Then, the regulating valve 40 is further closed so as to temporarily increase a suction amount in the transport pipe, and the granules are raised and transferred in the layered state. By this repeated operation, the granules are sent to a separator 14 in the layered state. Thus, the granules which are easy to be damaged and abraded can be carried securely.