| 摘要 |
<p>The invention relates to a process of recovering a non-ferrous metal from a dross containing the same. The process involves introducing into a furnace (preferably a rotary furnace) the dross and a coalescing aid for the metal, heating the dross and fluoride compound to a treatment temperature above the melting point of the metal, using a heating device which substantially maintains a non-oxidizing atmosphere in the furnace, agitating the dross until it reaches the treatment temperature, removing the molten metal thereby separated from a solid dross residue and removing the solid dross residue from the furnace. The coalescing aid is fluoride salt or mixture that remains substantially solid at the treatment temperature, for example, cryolite, recovered cryolite, AlF3 or NaF, or a mixture thereof. The salt or mixture remains in the dross during the process and does not make the dross become sticky, thus avoiding agglomeration of the dross particles. The use of the fluoride improves the rate of recovery of the metal content of the dross without producing environmental difficulties either during the heating operation or during the disposal or use of the dross residue.</p> |
