Patent ID: 8313690

Claim:
A direct smelting plant for producing molten metal from a metalliferous feed material using a molten bath based direct smelting process, the plant comprising: (a) a fixed direct smelting vessel to hold a molten bath of metal and slag and a gas space above the bath, the vessel including a hearth and a side wall; (b) a solids feed assembly to supply solid feed material, including metalliferous feed material and carbonaceous material, from a solid feed material supply location away from the vessel into the vessel; (c) an oxygen-containing gas feed assembly to supply an oxygen-containing gas from an oxygen-containing gas supply location away from the vessel into the vessel, the oxygen-containing gas feed assembly including: (i) a gas injection assembly including a plurality of gas injection lances to inject the oxygen-containing gas into the vessel, the gas injection lances extending through openings in the vessel, and (ii) a gas delivery duct assembly extending from a gas supply location away from the vessel to deliver the oxygen-containing gas to the gas injection assembly, the gas delivery duct assembly including a single gas supply main in the form of a ring main connected to the gas injection lances to supply the oxygen-containing gas from the gas supply location to the gas injection lances; (d) an offgas duct assembly to facilitate flow of offgas from the vessel, the offgas duct assembly including two offgas ducts of matching diameter extending outwardly from a cylindrical upper section of the side wall of the vessel, the offgas ducts being positioned below the ring main and above the plurality of gas injection lances, and wherein the offgas ducts are positioned with respect to the cylindrical upper section of the side wall so that central axes of the ducts intersect each other and intersect a point on a radial line that extends from a central vertical axis of the vessel away from the ducts; (e) a metal tapping assembly to tap molten metal from the bath during a smelting operation; and (f) a slag tapping assembly to tap slag from the bath during a smelting operation.