Abstract: A method for smelting reduction of iron ore comprises the steps of: preheating and prereducing iron ore; charging said preheated and prereduced iron ore, carbonaceous material and flux into a smelting reduction furnace; blowing oxygen gas through a top blow oxygen lance having decarburizing nozzles and post-combustion nozzles into said smelting reduction furnace, an end of said top blow oxygen lance being arranged between an upper side level of a slag layer and a lower side level of said slag layer; blowing a stirring gas through at least one side tuyere placed in side wall of said smelting furnace and at least one bottom tuyer placed in bottom wall of said reduction furnace so that at least part of said stirring gas introduced through at least one said side tuyere hits a swollen portion of the molten metal by said stirring gas introduced through at least one said bottom tuyere; and controlling a flow rate of said oxygen gas and said stirring gas blown in said smelting reduction furnace so that an OD of infur
Abstract: A method for smelting reduction of iron ore, comprises the steps of: introducing iron ore into a preheat and prereduction furnace and preheating and prereducing the iron ore, a prereduction degree being less than 30%; charging the iron ore, carbonaceous material and flux into a smelting reduction furnace; blowing oxygen gas, through decarburization nozzles and post-combustion nozzles placed in a top end of an oxygen lance, into the smelting reduction furnace, the top end of the oxygen lance being located so as to be between a top level and a bottom level of a slag layer; blowing a stirring gas through side tuyeres placed in a side wall and bottom tuyeres placed in a bottom wall of the smelting reduction furnace; and controlling a flow amount of the oxygen gas and the stirring gas so that an oxidation degree of an exhaust gas generated in the smelting reduction furnace ranges 0.4 to 0.9 and still a temperature of the exhaust gas ranges 300.degree. to 1300.degree. C.
Abstract: Energy for melting iron oxide or wustite is supplied by pre-heated natural gas which is combusted with oxygen in gaseous form and the oxygen contained in the preheated feed materials. Such combustion produces carbon monoxide and hydrogen gas, thus the combustion products are carbonizing to molten iron. The carbon monoxide and hydrogen evolved at the surface of the molten metal is post-combusted above the bath to form a mixture of carbon monoxide, carbon dioxide, hydrogen, steam and nitrogen. The heat generated by this post-combustion is sufficient to supply the energy for all chemical reaction requirements as well as to melt the wustite charge or smelt the preheated iron oxide charge.
Type:
Grant
Filed:
November 27, 1989
Date of Patent:
January 15, 1991
Assignee:
Midrex International BV, Rotterdam, Zurich Branch
Abstract: A method and apparatus for producing, in a reactor, a suitable prereduced product for final reduction from material containing metal oxide. The material is preheated in a fluidized bed by means of hot gases from a subsequent prereduction stage. The hot material is smelted and prereduced in a flame chamber utilizing hot reducing gases from a subsequent final reduction stage. The prereduced material is completely reduced in the final reduction stage.
Abstract: Described herein is a smelting reduction process for smelting and reducing an iron oxide material by introducing same into a smelting reduction furnace together with a solid carbonaceous material, a fluxing agent and an oxygen-containing gas, process comprising: subjecting part or all of the solid carbonaceous material to primary combustion using an oxygen-containing gas with an oxygen content corresponding to a theoretical air ratio of 0.4 to 0.9: separating the resulting reducing gas from combustion residue of the solid carbonaceous material; and introducing the reducing gas into a smelting reduction furnace to effect secondary combustion with supply of a separately introduced oxygen-containing gas for smelting and reducing said iron material.
Abstract: A method for smelting and reducing iron ores comprises the steps of: the step of preheating and prereducing iron ores; the step of charging the preheated and prereduced iron ores into a smelting reduction furnace; the step of charging carbonaceous material and fluxing material into the smelting reduction furnace; the step of blowing in oxygen gas into the smelting reduction furnace through a top-blow oxygen lance having decarbonizing nozzles and post combustion nozzles; and the step of blowing in stirring gas through side and bottom tuyeres set respectively in a side wall and a bottom of the smelting reduction furnace.