The invention relates to a processing system (1) andto a method for processing in particular pharmaceuticalpowders. The processing device (5) comprises a plurality ofconverting stations (41, 42) which are employed in a cyclicalmanner. The processing system (1) displays at least one firstzone (I) and one second zone (II), wherein each zone (I, II)is in each case assigned at least one converting station (41,42) of the processing device (5). A cleaning tunnel (44)which transgresses at least one converting station (42) ofthe second zone (II) is disposed in the second zone (II). Afirst end (45) of the cleaning tunnel (45) adjoins the firstzone (I). A suction installation (6) is disposed in theregion of an opposite second end (46) of the cleaning tunnel(44). By means of the suction installation (6), a purifying-gas stream (56) is generated in the cleaning tunnel (44).
