Method of reducing the iron content of steel slag
AssigneeIpcor NV
InventorDirk Guustaaf Mantel
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Abstract
A method of reducing the iron content of starting material containing calcium, silicon and oxygen, and iron in the form of a ferrite and/or oxide, for example a steel slag, includes the steps of heating the starting material to a temperature of at least 800° C. and preferably between 900° C. and 1150° C. inclusive, in the presence of a reductant such as carbon monoxide and in the presence of a siliceous material with which non-ferrous oxides released during the reduction form high melting point compounds, to produce a magnetic form of iron, and removing at least some of the magnetic form of iron to produce a product, which may be used as a raw material in the cement industry.
Claims14
A method of reducing the iron content of a steel slag starting material that contains calcium, silicon, and oxygen and iron in the form of at least one of a ferrite and an oxide, which includes the steps of:
- (i) heating the starting material in finely divided form together with a reductant and a siliceous material, which forms high melting point compounds with non-ferrous oxides released during the reduction, by means of a cyclone suspension heat exchanger to a temperature from 800° C. to 1050° C. to form a magnetic form of iron;
- and
- (ii) removing at least some of the magnetic form of iron.
Dependencies are inferred from the claim text.