Patent ID: 6387153
Filing Date: 2002-05-14
Classification: C21C

Abstract:
A process for producing molten metal from a metalliferous feed material in a vessel that contains a molten bath having a metal layer and a slag layer on the metal layer, the process comprising:(a) injecting carrier gas, metalliferous feed material, and solid carbonaceous material, and optionally fluxes, into the molten bath via a plurality of solid material injection lances/tuyeres positioned above and extending towards the surface of the metal layer and causing molten material to be projected from the molten bath as splashes, droplets and streams into a space above a nominal quiescent surface of the molten bath to form a transition zone; (b) smelting metalliferous feed material to metal in the molten bath; (c) injecting oxygen-containing gas into the vessel via one or more than one lance/tuyere and post-combusting reaction gases released from the molten bath, whereby the ascending and thereafter descending splashes, droplets and streams of molten material in the transition zone facilitate heat transfer to the molten bath; (d) tapping molten metal and molten slag as required from the vessel; and (e) a hold procedure for situations in which it is necessary to stop production of molten metal for a period of time other than situations in which there has been an interruption to the supply of oxygen-containing gas and/or solid carbonaceous material to the process, the hold procedure comprises: (i) stopping supply of metalliferous feed material into the vessel; (ii) continuing to inject carrier gas and solid carbonaceous material into the molten bath via the solid material injection lances/tuyeres and generating combustible material in the metal layer and causing molten material and combustible material to be projected into the transition zone; and (iii) continuing to inject oxygen-containing gas into the vessel via one or more than one lance/tuyere and combusting combustible material projected into the transition zone, whereby the ascending and thereafter descending splashes, droplets and streams of molten material in the transition zone facilitate heat transfer to the molten bath to maintain the temperature of the molten bath above a temperature at which the bath freezes.