Refuse washer for the removal of toxic substances

摘要

Refuse, especially from the streets, needs to be separated from toxic materials that must not enter the dumpsite. Refuse is fed into the washer where it falls through agitated water and is directed by the tapered sides of the vessel into an open screw conveyor (8). The conveyor rises at an angle of more than 30 deg and passes through a closed housing (9) outside the washer to its discharge. The conveyor is driven, and supported, only at its upper end (9a). A plate (15) above the conveyor screw prevents extrusion of the compressed material back into the washer along most of its open portion but stops short of the closed portion of (9) to allow pressure relief. Water is fed at (7) into a distributor (5) at the low end of the screw. At the same time compressed air is fed into (5) at (6) as an agitating medium and also to create large bubbles which float off light refuse that eventually passes over a weir at (14).