Abstract: The invention provides a method and an apparatus for separating and collecting fibrous material in a silo having a side wall defining an interior for storing fibrous material and having an inlet and outlet, the apparatus comprising a flat disc having a perforated portion and an imperforate annular edge portion and mounted for rotation on a horizontal shaft in the interior of the silo adjacent the outlet, a driving device for rotating the disc, an inlet conduit connected to said inlet for impingement of the pneumatically conveyed air-fibrous material mixture on the disc, a suction conduit connected to said outlet and having an end edge projecting into the silo and disposed in closely spaced relationship with the imperforate annular portion of the disc, to provide, during the rotation of the disc, an aerodynamic seal formed in an annular duct defined between the annular imperforate portion of the disc, the side wall of the silo and the outer surface near the edge of the suction conduit, the suction conduit draw