| 摘要 |
<p>PURPOSE:To recover valuable metals and free acids from factory waste by leaching a waste metallic oxide/metal mixture with a waste acid, subjecting the liquid to diffusion dialysis after leaching, recovering the free acids therefrom and recovering the metals from the liquid after the dialysis. CONSTITUTION:The waste metallic oxide/metal mixture obtd. after metallic lumps are recovered by screening from the slag generated from a melting stage of a metal working factory is crushed to about -40-80 mesh. The crushed matter is subjected to the selective leaching of the metallic oxides with the waste acid generated in a pickling stage while air is blown thereto at about 40-90 deg.C. The metals are thereby recovered. The liquid after the leaching is subjected to the diffusion dialysis by using an ion exchange membrane while water is properly added thereto. The free acids such as sulfuric acid are thus recovered. The liquid after the dialysis is further subjected to solvent extraction after partial neutralization and the metals are recovered therefrom by back extraction, electrolysis, cementation, etc.</p> |
