Patent ID: 7641712

Claim:
A method for use in production of metallic iron nuggets comprising the steps of: providing a hearth comprising refractory material; providing reducible mixture above at least a portion of the hearth where the reducible mixture comprises: reducible iron bearing material, reducing material such that the reducible mixture has a quantity of reducible iron bearing material and between about 70 percent and about 90 percent of a stoichiometric amount of reducing material necessary for complete iron reduction of the reducible iron material, and one or more additives selected from the group consisting of calcium oxide, one or more compounds capable of producing calcium oxide upon thermal decomposition thereof, sodium oxide, and one or more compounds capable of producing sodium oxide upon thermal decomposition thereof, and at least one fluxing agent selected from the group consisting of fluorspar, CaF 2 , borax, NaF, and aluminum smelting industry slag; and thermally treating the reducible mixture in the presence of other carbonaceous material separate from the reducible mixture to form one or more metallic iron nuggets by melting.