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US 2025/0146091 A1Published application
Method for treating steel mill slag
AssigneeOcs 2 Ug (HaftungsbeschräNkt)
InventorGünther BELLMANN
Life of this patent
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Abstract
The method according to the invention for treating steel mill slag includes the steps of A) providing steel mill slag in solid form having a fineness such that the steel mill slag has a specific surface area according to BET of 0.1 m2/g or more; step B) treating the steel mill slag by heating it to a temperature of at least 800° Celsius, while adding oxidizing agents and auxiliary agents; and step C) separating iron (III) oxide and iron (II,III) oxide out of the treated steel mill slag.
Claims15
A method for treating steel mill slag comprising the following steps:
- A) providing steel mill slag, which, when solidified, has iron (II) oxide (FeO) and, if solidified, has a fineness such that the steel mill slag has a specific surface area according to BET of 0.1 m2/g or more;
- B) treating the steel mill slag at a temperature of at least 600° C., while adding oxidising agents and auxiliary agents,
- a) wherein the oxidising agents oxidise at least a part of the iron (II) oxide (FeO) present to iron (III) oxide (Fe2O3) and/or iron (II,III) oxide (Fe3O4) and
- b) wherein the auxiliary agents form a bond at least with calcium from calcium-iron compound present and bound in the steel mill slag and
- b1) thereby release iron (III) oxide (Fe2O3) and/or iron (II,III) oxide (Fe3O4) and
- b2) further increase the proportion of 2 CaO·SiO2 (belite) and/or other calcium silicates, such as alite, wollastonite and/or rankinite, in the treated steel mill slag,
- C) separating iron (III) oxide (Fe2O3) and iron (II,III) oxide (Fe3O4) out of the treated steel mill slag.
4 more elements
Dependencies are inferred from the claim text.