To provide an arrangement permitting fiber floccules to be pneumatically conveyed to a downstream-connected device, and for the sake thereof, making it possible to form a conveying air stream with constant or essentially constant volume.

The arrangement has the following scheme. An essentially vertical filling chute 16 is provided. A pneumatic fiber feeder 2 is assigned to the upper intake opening for the chute while a flocculation device 4 having a draw-in roll and a fast-rotating opening roll 4e is assigned to the lower exit opening. At least one air-permeable surface 10 for filtering out (separating out) a fiber material from a conveying air stream and a device 9 for evacuating the conveying air stream are provided, wherein the conveying air stream is guided along the opening roll. A partial air stream F of the separated out conveying air stream E is guided into an exhaust air device 12 equipped with an air stream regulator 14 inside, the air stream regulator 14 being connected to a control or regulating device 18.