RECLAIMING FOUNDRY SAND BY GRAVITY FLOW SYSTEM

摘要

A method of reclaiming foundry sand by (a)providing a treatment tower having a plurality of heatconductive tubes extending across the interior of thetreatment tower, the tubes being arranged in rows andstaggered with respect to tubes in adjacent rows tocreate close spacing therebetween sufficient to permitthe sand to flow continuously and non-turbulently alongthe contours of the exterior under the influence ofgravity before dropping to the next adjacent tube tothereby again flow continuously and non-turbulently insuccessive sequence downwardly of the tower; (b)quiescently heating the interior tower space and tubes toa temperature in excess of 1300°F and introducingsufficient air or oxygen to permit combustion of theresin binder; and ( c) feeding particulated sand to thetop of the tower and tubes whereby such sand controllablyflows along and through such labyrinth of tube spacingswith little or no dwell on each contacted tube and in atime period of 5-15 seconds, said sand exiting from thebottom of said tower with said binder having beencombusted to form a gas that is extracted from the top ofthe tower.