Production of blister copper directly from dead roasted-copper-iron concentrates using a shallow bed reactor

A method of producing blister copper from copper-iron sulfide concentrate containing by weight about 15 to 45% Cu, about 15 to 40% Fe, about 20 to 45% S, the total Cu, Fe and S content being at least about 85% and the balance gangue and residual metals which comprises,

• dead roasting said sulfide concentrate at a temperature above 800.degree. C to remove sulfur therefrom and form ferric iron oxide as evidenced by the formation of substantial amounts of magnetic copper ferrite,
• forming a batch mixture of said roasted concentrate together with a slagging agent comprising SiO.sub.2,
• the amount of SiO.sub.2 present being sufficient to combine with FeO reduced from said ferric iron oxide and provide a slag having a melting point below about 1250.degree. C,
• forming agglomerates from said batch mixture,
• charging said agglomerates into a shallow bed reactor furnace together with an amount of carbonaceous material correlated to reduce copper oxide therein and ferric iron oxide to FeO and provide sufficient heat to effect smelting in said furnace, said charge forming a shallow bed disposed above a tuyere line located peripherally around said furnace, said shallow bed charge ranging up to about 6 feet in height, igniting said carbonaceous material in said shallow bed and blasting air through said bed via said tuyeres, thereby heating and rapidly smelting said batch by raising the temperature thereof in excess of the melting point of copper,
• said charge being maintained in said furnace for a residence time of less than about 1 hour sufficient to reduce said copper oxide selectively to molten blister copper and reduce ferric iron oxide to ferrous oxide to combine with the SiO.sub.2 present to form a molten slag, and
• allowing said molten copper and said molten slag to settle by gravity in said furnace into a confining hearth located at the bottom of said furnace to produce a pool of blister copper with a layer of said molten slag on the top thereof.