Copper Enrichment from Copper contained Iron Scrap by Liquid Phase Separation of the Fe-Cu-P System

在日本，来自焚烧炉或焚烧炉底灰的熔化炉的金属残留量已经增加。金属残留物中含有铜、银、金等有价值的金属。金属残渣的主要成分是铜、磷、硅和铁，其余为铁。针对传统铜冶炼厂铜含量低，难以回收有价金属的问题，研究了利用熔融金属体系相分离法提质有价金属的新途径。尽管铁和铜的二元熔体在所有组成上是可混溶的，但向二元熔体中添加碳或磷导致铁相与铜相之间的相分离。吸附贵金属的铜相在常规铜熔炼炉中精炼是可行的。介绍了相分离、铜回收率和有价金属分配比的基本情况，根据本研究得到的质量平衡反应和铜在铁相中的溶解度以及铁在铜相中的溶解度，计算了含铁和铜的焚烧金属渣中铜的回收率。假设铜相中的铜全部回收，溶解在铁相中的铜损失，则铜回收率相对于残渣中的铜品位表示，如图8所示。当应用Cu-Fe-P体系的相分离进行铜回收时，从含10%和30%铜的金属残渣中铜的回收率分别为35%和80%。另一方面，用Cu-Fe-P-C体系的相分离，从含10和30%铜的金属残渣中库珀的回收率分别为50和90%，银、金、钯、铂和铑的分配比列于表II中。金、银、钯富集在铜相中，而铑则更多地分布在铁相中。铂在两相中的分布比较均匀。

Amount of metal residue from incinerators or melting furnaces of incinerator bottom ash has been increased in Japan. The metal residue contains valuable metals such as copper, silver and gold. Main components of the metal residue are copper, phosphorus, silicon and iron of the remainder. Copper content is 5 to 20% and too low to recover the valuable metals in a conventional copper smelter, so a new approach to upgrading the valuable metals with phase separation in molten metal system was researched. Whereas the binary melt of iron and copper is miscible over all composition, the addition of carbon or phosphorus to the binary melt leads to phase separation between an iron phase and a copper phase. The copper phase absorbing the precious metals is feasible for refining in a conventional copper smelter. Fundamental information about the phase separation, recovery of copper and distribution ratio of the valuable metals are presented.Based on the mass-balance reaction and the solubility of copper in iron and iron in copper phases obtained in this study, copper recovery from the incineration metal residue containing iron and copper was calculated. Assuming that all copper in copper phase is recovered, and the copper dissolved in iron phase is loss, copper recovery is represented against copper grade in residue as shown in Fig. 8. When copper recovery by applying the phase separation of Cu-Fe-P system is carried out, copper recoveries from metal residues containing 10 and 30% copper are 35 and 80%, respectively. On the other hand, cooper recoveries with the phase separation of Cu-Fe-P-C system are 50 and 90% from metal residues containing 10 and 30% copper, respectively.The distribution ratios of silver, gold, palladium, platinum and rhodium are listed in Table II. We can recognize the gold, silver and palladium are enriched in copper phase, on the contrary rhodium is more distributed to iron phase than to copper. Platinum is comparatively distributed to both phases.