Process for the reclamation of used foundry sand

摘要

An apparatus for reclaiming used foundry and molding sand comprises a container having a cylinder sidewall and at least one bottom wall or tray is arranged on a sand reclamation device for the mechanical cleaning of grains of sand, particularly organically and inorganically bonded molding sands. A central, hollow drive shaft is arranged in the cylinder and is supported for rotation. The bottom walls are firmly attached to the hollow shaft. A slot is formed between the bottom walls and cylinder. By the rotation of the bottom walls a parting plane is formed between the rotating part and the stationary part of the column of sand, in which plane an intensive rubbing of grain against grain takes place. As a result of the cylindrical force, the sand is brought in the direction towards the wall of the cylinder and through the slot, which additionally leads to an intensive rubbing of grain against grain. The powder produced upon the rubbing, primarily binder particles which have been rubbed off, is drawn off continuously through the hollow shaft by means of the suction via openings which are provided in the hollow shaft.