Within foundries sand is used to form moulds into which molten metal is poured to make castings. The sand forming the mould is given strength by adding a binder which may be a resin or clay. After the casting has solidified the metal component is released from the mould at the “shake out”. The shakeout could be a large vibrating screen or a rotating drum which repeatedly lifts and drops the casting and sand mound assembly. Within the shakeout the mould is broken releasing the casting and separating the sand. The sand will then be reclaimed and reprocessed to allow its repeated use. Dust and sometimes residual moisture are released in the shakeout process. There may often be visible water vapour in the emission although not if chemically bonded sand is employed in the mould. Historically a wet scrubber such as the AAF RotoClone type N was the automatic choice for this application because of the water vapour however the increasing use of chemically bonded dry sands and the ability of a modern bag filter to deal with moist air by using thermal insulation and a gas burner to raise the temperature of the air being filtered means that a bag filter such as AAF FabriPulse Fusion – when carefully applied – is often the first choice.