Materials re-processing often includes a shredding process which when followed by an air swept separator allows for the segregation of different material streams for reprocessing. Because of the wide range of materials that may pass through the shredder the downstream air pollution control equipment has to be capable of reliable performance regardless of what unexpected pollutants that it may be faced with. These could, and do, from time to time include explosive dusts and vapours. The AAF RotoClone type N is ideal. Paper and board (cardboard) shredding also requires a downstream scrubber and in this case the AAF RotoClone type W compact scrubber is the recommended choice.