PURPOSE: To efficiently carry out suction and discharge of rice straw waste and to prevent clogging of the waste to a passageway, by horizontally setting a part corresponding to a dust sending port of a handling barrel of a selecting member and upward slanting a part influenced by sucking action of a cross-sectional flow fan by suction at the rear part.

CONSTITUTION: A part corresponding to the lower part of a dust sending port 14 of a handling barrel of a transporting and selecting member 6 is horizontally made and constitutes a receiving part A. A part behind the receiving part A of the transporting and selecting member 6, namely a part being influenced by sucking action from a suction hole 15-3 through a positioned cross-sectional flow fan 16 by suction is upward slanted at the rear part and comprises a sucking action part B.