Process for mechanically cleaning a powder and apparatus for making the same

摘要

In the invented process for mechanically cleaning a powder, particularly powder aluminium oxide (25) the powder is projected at a predetermined speed ranging from 20 to 30 m/s and at a frequency higher than 10 se1 during a defined time against at least one surface in order to separate therefrom particles of impurities (35) that adhere to its surface. The thus obtained powders particularly aluminium oxides (30, 31) and impurities (35) are then sorted according to size. A cleaning apparatus (1) for carrying out the process has a separator (2) that is designed as an impact mill and is mounted upstream of a wind sifter (3) or a cyclone. A simplified embodiment of the cleaning apparatus (1) has only a wind sifter (3).