摘要 |
<p>A metallurgical residue comprising non-ferrous metal is charged on the heel contained in plasma arc electric furnace and metallurgical residues are fused in fluid slag at slag/copper bath interface. The non-ferrous metals in the residue are reduced to the oxidation state of zero. The copper heel is stirred intensely by injecting inert gas, preferably nitrogen and/or argon such that formation of crust is prevented and reduction reaction is accelerated. Then, copper-miscible non-ferrous metal is injected into the copper heel. Thus, the non-ferrous metal is recovered. A metallurgical residue comprising non-ferrous metal is charged on the heel contained in the plasma arc electric furnace and metallurgical residues are fused in the fluid slag at slag/copper bath interface. The non-ferrous metals in the residue are reduced to the oxidation state of zero. The copper heel is stirred intensely by injecting inert gas, preferably nitrogen and/or argon such that the formation of crust is prevented and reduction reaction is accelerated. Then, the copper-miscible non-ferrous metal is injected into the copper heel. Thus, the non-ferrous metal is recovered. The alternating current type plasma arc electric furnace comprises several electrode and liquid copper heel which is covered by fluid slag comprising at least one fusion-reduction phase. The reduction process is carried out in presence of carbon, preferably anthracite or calcium oxide. The method further recovers volatile heavy metals such as zinc and lead. The method involves oxidation of iron and metals having high oxidization than iron such as silicon, manganese or aluminum. The method further recovers molybdenum oxide.</p> |