| 摘要 |
1318977 Treatment of pyrite cinders EMPRESA AUXILIAR DE LA INDUSTRIA SA 23 Oct 1970 [31 Oct 1969] 50594/70 Heading C1A Pyrite cinders containing oxidizable sulphur are heated in an oxidizing atmosphere containing SO 2 in an amount not greater than 14% by vol., and O 2 at a temp., e.g. 300-750‹ C. sufficient to form sulphates of, e.g. Cu and Zn. The oxidizing atmosphere may contain 5-21% by vol. O 2 . The temp. of heating may be controlled by the variation of the solid/gas ratio, and by the introduction of cooling surfaces, water or washing acids into the cinders. A fluidized bed may be used. In an example the cinders produced in the single-stage roasting of pyrites at 850‹ C. containing γFe 2 O 4 , Cu, Zn, Pb, As and S is contacted in a fluidized bed with a gas stream containing 8% SO 2 and 10% O 2 at a temp. of 500‹ C. The resulting cinders contain iron as hematite and Cu and Zn as easily leachable sulphates. |
