534
N. Okajima et al.
Role of the HMC in Copper Smelting
An outline of the Cu smelter and HMC flowsheet is shown in Fig. 4. In this process,
eleven non-ferrous metals are recovered efficiently from recycled raw materials and
intermediates of copper smelting by combining pyro- and hydrometallurgical processes with technologies that have been developed in our non-ferrous smelting and
refining businesses [1].
The compositions of the intermediates of copper smelting, i.e., Pb sulfate and a
residue from copper electrolyte purification, are shown in Table 1. Sb is an inhibitor
of the electrorefining process. Increases in antimony concentrations in the anode
and electrolyte cause the formation of suspended solids in the electrolyte and Pb
decreases the current efficiency [2].
Fig. 4 Relationship between copper smelter and HMC
Table 1 Composition of intermediates of copper smelting process (%)
Pb
Sn
Sb
Bi
Cu
Pb sulfate
23–30
8–14
0.3–0.6
5–8
0.7–0.9
Residue from Tankhouse
–
–
20–27
20–22
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