| 摘要 |
Solid state iron oxide reduction in a gas-solid reduction zone is combined with continuous melting of the hot solid reduced iron in a fuel-fired gas-solid-liquid melting zone within a rotary furnace by pneumatic transfer of the hot reduced iron by carrier gases through a transfer duct connected into an injection lance projecting into the melting zone and carrying a nozzle which directs a jet of hot reduced iron downwards into the metal bath, with a preferred embodiment of continually traversing the lance and thereby the jet of carrier gases and hot reduced iron longitudinally forwards and backwards enhancing heat transfer. The invention embraces a broad range of known solid-state reduction processes, classified either as: Group A. those employing gases within a gravity contact-supported or fluidized moving bed at substantial pressures of 1-5 atmospheres; or Group B. solid carbonaceous reductants in a rotary kiln or rotary hearth conducted at near ambient atmospheric pressure. A preferred embodiment applied to Group A reduction includes in situ reforming of a major portion of the hydrocarbons applied as reducing gases in the reduction zone, in combination with reforming a minor portion by partial oxidation with oxygen. The process provides for a high degree of in-process post-combustion with oxygen in the melting zone and various other preferred features to improve energy requirements, production rates, yields, costs and control of the liquid iron and steel product composition and quality in relation to the prior art.
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