Abstract: Waste paper contains sticky foreign material, and the recovery and sending of this sticky foreign material to a paper-making process together with fiber is liable to lead not only to the sticky foreign material sticking to and contaminating the paper making machine or dryer but also paper peeling and tearing, causing a decline in paper quality.

Abstract: In vertical concentrating washing machines, processed raw material is transported upward but ends up containing shower water. That is, the moisture content ends up increasing during the transport process even though the material has been dewatered. A transport blade (8) has a plate-like shape in plan view and includes a fan-shaped portion (10) that extends rearward in the rotational direction, developing into a fan shape, and the transport blade is attached such that a plate surface thereof has a slanted orientation with respect to the axis direction of a rotary shaft (6), with a forward side, in the rotational direction, of the plate surface being disposed lower than a rearward side thereof. A plurality of the transport blades (8) is attached so as to delineate a helix along the circumferential direction of the rotary shaft (6) while leaving a communicating portion that is straight in the vertical direction. Shower water falls from gaps (S) between the transport blade (8).