| 摘要 |
<p>PURPOSE:To recover efficiently valuable metals with a small amount of reducing agent and fuel by charging dust containing the valuable metals and iron and the solid carbonaceous reducing agent to a kiln toreduce the metals and by oxidizing the produced FeO to generate a high temp. CONSTITUTION:Materials to be treated consisting of dust, etc. containing the valuable metals such as Zn, Pb, Cd and Fe group metals are charged together with a reducing agent of solid carbonaceous materials consisting of coke and coal corresponding to the total amount of (1) necessary for reducing the valuable metals contained in the materials to be treated, (2) necessary for reducing Fe component nearly to FeO, and (3) the amount equal to or less than above-mentioned amount (1)+(2), to a rotary kiln 1 from a dust feeding chute 4. The fuel is jetted from a burner 5 under high pressure, the inner pressure of the kiln 1 is maintained to positive pressure and the discharging side and the other sides are maintained to oxidizing and reducing atmospheres, respectively. Thus the valuable metals are reduced and vaporized and recovered as the oxides by a cyclone 8 and a dust collector 9 of bag filter type. Fe is recovered as the oxide and taken out through a chute 13 and a rotary cooler 14.</p> |
