| 摘要 |
<p>The process includes the steps of heating a charge of ore in a furnace having a reducing atmosphere therein comprising a mixture of reconditioned and recycled top gas from the reducing furnace and off-gas rich in hydrogen and carbon monoxide produced by a melting unit to reduce the ore to partially carburized iron, and melting the product together with scrap, slag forming additives and fluxes in a melting unit having a reducing atmosphere therein produced by the combustion of a rich fuel/oxidant mixture to form a molten slag and molten iron suitable for the further refining to produce steel. In an alternative form of the process, the reduced and carburized iron is cooled within or outside the reducing furnace to form prereduced metal pellets suitable for the use as a part of the burden in a melting unit. The apparatus comprises a refractory lined cupola melting unit portion equipped with burners capable of burning a rich fuel/oxidant mixture to produce a reducing atmosphere within the melting unit and off-gas rich in gaseous reductants, a direct reducing unit portion communicating with the upper end of the melting unit to receive the melting unit off-gas, and recirculating and conditioning means to recycle at least a portion of the top gas from the upper region of the reducing portion to the lower region of the reducing unit portion.</p> |
