Abstract: A method of reclaiming foundry sand by (a) providing a treatment tower having a plurality of heat conductive tubes extending across the interior of the treatment tower, the tubes being arranged in rows and staggered with respect to tubes in adjacent rows to create close spacing therebetween sufficient to permit the sand to flow continuously and non-turbulently along the contours of the exterior under the influence of gravity before dropping to the next adjacent tube to thereby again flow continuously and non-turbulently in successive sequence downwardly of the tower; (b) quiescently heating the interior tower space and tubes to a temperature in excess of 1300.degree. F.

Abstract: A heat exchanger is disclosed which comprises an outer shell, a bundle of heat exchange tubes within the shell and positioned within a tube sheet adjacent one end thereof, and a shroud spaced between the shell and the tubes. The exchanger is constructed so that hot incoming fluid passes over the heat exchange tubes inside of the shroud and then, in its cooled state, passes along the back face of the tube sheet and between the outer surface of the shroud and the inner surface of the shell, so that thermal stresses in the tube sheet are minimized.