1505904 Reclaiming moulding sand SOC D'APPLICATIONS DE PROCEDES INDUSTRIELS ET CHIMIQUES 10 June 1975 [10 June 1974] 24832/75 Heading B3G Binding agents, for example, are removed from the surface of foundry moulding sand by introducing encrusted sand particles into a gas stream and projecting them against the inner surface of a rotating drum. In Fig. 2 a drum 1, which may be circular in cross-section, is rotated about its horizontal axis and contains a stationary tube 12 with slits in its wall through which streams of air are discharged. The sand falls into the streams via a bonnet 15 from pockets 22 in baffles 8 which convey the same upwardly from the drum bottom. In other embodiments two tubes 12 are provided and some of the drum walls are perforated for the outflow of sand grains freed of their gangue. Waste and fines in dust form may be carried away in an air current.
