Patent ID: 8043408

Claim:
A process for producing lead and zinc from concentrates of zinc and lead sulfides or oxides, comprising the steps of: (a) mixing zinc ore and/or lead ore concentrates, iron bearing and carbon containing materials; metallic iron fines and iron oxide fines; carbonaceous reductant; fluxing agent; and a binder to form a mixture; (b) forming agglomerates from said mixture; (c) introducing said agglomerates to a melting furnace; (d) preventing substantially all air ingress to the melting furnace and maintaining a reducing atmosphere within the melting furnace; (e) forming a liquid iron-iron sulfide mixture in the melting furnace; removing the liquid iron-iron sulfide mixture from the melting furnace, desulfurizing the iron, and solidifying the resulting iron for further use: (f) vaporizing lead and zinc in the melting furnace at a temperature of 1000 to 1650 C, forming metal vapors, and removing the lead and zinc from the melting furnace in vaporized form; (g) cooling and condensing the metal vapors to liquid metal; (h) separating the zinc and lead; (i) recovering the lead and zinc metal separately; (j) forming off-gases in the melting furnace, cleaning and cooling the off-gases, and utilizing the cleaned off-gases as combustion fuel to drive a turbine and to generate electricity; and (k) producing off-gases in the turbine, recovering the off-gases from the turbine and recovering the sensible heat contained therein as steam in a waste heat boiler recovery system.