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US 4,304,595 AGranted
Method of manufacturing crude iron from sulphidic iron-containing material
AssigneeBoliden Aktiebolag
InventorStig A. Peterson
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AssigneeBoliden Aktiebolag
InventorStig A. Peterson
Estimating the term…
A method of producing crude iron from sulphidic iron-containing material, where an iron sulphide containing material is charged to a furnace space and there, together with a silica containing material and oxygen, is smelted to an iron-silicate smelt during combustion of sulphidebound sulphur present, so that said smelt contains approximately 70-90% by weight iron calculated as iron (II) oxide. To the smelt is then added a reducing agent in a manner such that the iron content calculated as iron (II) oxide falls to approximately 60% by weight or lower in the presence of lime and/or other fluxing agents and that formed crude iron is separated. The iron content of the iron silicate smelt is then increased by adding further iron sulphide containing material and oxygen for smelting and reducing agent for another reduction.
A method for producing crude iron from iron sulphide containing materials comprising charging the iron sulphide containing material to a furnace space, smelting the same together with a silica containing material and oxygen to an iron silicate smelt during combustion of sulphide-bound sulphur present, so that said smelt contains approximately 70-90% by weight iron calculated as iron (II) oxide, adding a reducing agent to said iron silicate smelt in a manner such that the iron content calculated as iron (II) oxide falls to approximately 60% by weight or lower in the presence of lime and/or other fluxing agents, separating crude iron formed, charging further iron sulphide containing material to the furnace space containing already formed iron silicate smelt and smelting the same by adding oxygen so that the iron content is again increased in the iron silicate smelt and adding a reducing agent for a further reduction in iron content.
A method for producing crude iron from iron sulphide containing materials comprising charging the iron sulphide containing material to a smelting furnace, smelting the same together with a silica containing material and oxygen to an iron silicate smelt during combustion of sulphide-bound sulphur present, so that said smelt contains approximately 70-90% by weight iron calculated as iron (II) oxide, transferring said smelt to a reduction furnace, adding a reducing agent to said iron silicate smelt in a manner such that the iron content calculated as iron(II) oxide falls to approximately 60% by weight or lower in the presence of lime and/or other fluxing agents, separating crude iron formed returning iron silicate smelt to said smelting furnace, charging further iron sulphide containing material to the smelting furnace and smelting the same by adding oxygen so that the iron content is again increased in the iron silicate smelt, and transferring said smelt to said reduction furnace to which is added a reducing agent for again reducing the iron content.
Dependencies are inferred from the claim text.