摘要 |
The invention relates to a process for the mechanical cleaning of foundry used sand by means of thermomechanical regenerations, in which the sand is blown pneumatically against a deflection hood and the mechanical-pneumatic cleaning is performed batchwise in a separate container. The process can be used both as pre-cleaning and as after-cleaning. In the case of pre-cleaning there is a simultaneous drying, preheating, pre-cleaning and sifting, whereas with after-cleaning there is a simultaneous cooling, after-cleaning and sifting. As a result of the batchwise operation, all the quartz particles are exposed roughly to the same friction treatment and consequently, in conjunction with a simple control of the cleaning process, reduced grain destruction is achieved. |