ZINC RECOVERY AS A SOLUBLE SALT AND IRON AS OXIDES FROM GRANULATED SLAG PRODUCED BY THE LEAD EXTRACTION IN A CIVIL WORK.

摘要

The present disclosure is related to the development of the hydrometallurgical and the secondary pyrometallurgical process, for the Zinc recovery as sulfates and iron as oxides coming from granulated slag, as a result of the lead ore smelting in blast furnaces. The process consists in grinding the slag and then treating the same with concentrated sulfuric acid, generating an exothermic reaction; the product obtained from this treatment is leached, to subsequently separate the soluble salts, which later are crystallized and then subjected to a heat treatment in order to convert the iron into oxides, while the zinc sulfate remains unchanged. The product of this roasting is leached to separate the iron oxides from the soluble zinc salts.