Abstract: A method and apparatus are shown for improving the collapsibility characteristics of foundry cores and molds after being contacted with a heated, cast product. The foundry cores/molds are contacted with an oxidant impregnating liquid after being formed and prior to contact with the heated, cast product. The heat of the cast product is sufficient to sustain combustion of the chemical coating of the sand particles making up the cores/molds to facilitate removal with a minimum of force after casting.

Abstract: The waste sands are passed to a calcining chamber having a floor, connecting sidewalls and a top. The floor of the calcining chambers provided with a plurality of vents. The calcining chambers also connected to a separate firebox which produces fluidizing hot gases for fluidizing waste sands within the calcining chamber and forming a fluidized sand bed. The fluidizing hot gases are introduced into the calcining chamber by means of the floor vents. By precisely controlling the temperature of the waste sands within the fluidized bed, a more consistent product is produced while maintaining the temperature of the waste sands below a critical temperature at which the organic binders present on the sand grains would be fused to the waste sand grains.

Abstract: Hazardous substances are separated from used foundry sand by means of a triple fluid bed thermal reactor, second stage sand cooler and third stage pneumatic attrition scrubber. Temperatures in each of the reactor's beds are precisely controlled, depending upon the nature of the sand being treated, so that hazardous substances can be separated and disposed of, rather than fixing the substances onto the sand grains in insoluble form.

Abstract: A method and apparatus for reclaiming used foundry sands including organic resin-bonded sands and clay-bonded sands is shown. The method includes passing used sand downward through a series of vertical, fluid sand beds. Hot air is forced upward in countercurrent fashion through the beds in turn so that a boiling action is achieved in the sand masses. The combination of thermal and abrasive action removes both organic resin and clay-bonded materials from the sand in one continuous operation.

Abstract: Used foundry sand is passed downward through a series of vertical, fluid sand beds. Hot air is forced upward in countercurrent fashion through the beds in turn so that a boiling action is achieved in the sand masses. The combination of thermal and abrasive action removes both organic resin and clay-bonded materials from the sand in one continuous operation.