Use of tail gas made of the discharged gas of a reduction process of iron oxide-containing material

Patent metadata

Field	Value
Publication number	US-2026035758-A1
Application number	US-202319139437-A
Country	US
Kind code	A1
Filing date	Dec 13, 2023
Priority date	Dec 20, 2022
Publication date	Feb 5, 2026
Grant date	—

Abstract

A method for producing molten iron. The reduction of iron oxide-containing material to form a metallized product is performed using a reduction gas consisting at least largely of hydrogen H2. Top gas is accumulated during the reduction process. First sub-quantity of top gas is combined with reducing reduction gas components to provide reduction gas, and second sub-quantity of the top gas, as a discharged gas, is subjected to a gas separation process into a hydrogen-enriched gas flow and a hydrogen-depleted tail gas flow. Metallized product of the reduction process is combined with carbon carriers to be melted in a melting device to form a molten iron, and a smelting exhaust gas is accumulated. Sub-quantity of the tail gas flow is combined with at least a sub-quantity of the smelting exhaust gas, and a tail gas mixture is produced. Sub-quantity of the tail gas mixture is supplied to a thermal use.

First claim

1 - 8 . (canceled)

9 . A method for producing an iron melt, comprising:
reducing iron oxide-containing material to obtain a metallized product using a reduction gas composed at least predominantly of hydrogen H2; generating top gas by the reducing operation; combining a first sub-amount of the top gas with reducing reduction gas components to prepare reduction gas; separating, using a gas separation apparatus, a second sub-amount of the top gas as discharge gas into a hydrogen-enriched gas stream and into a hydrogen-depleted tail gas stream; melting, in a melting apparatus, the metallized product of the reduction combined with carbon carriers to obtain an iron melt, a melting offgas being generated; combining at least a sub-amount of the tail gas stream with at least a sub-amount of the melting offgas to form a tail gas mixture; and sending at least a sub-amount of the tail gas mixture to a thermal utilization.

10 . The method as claimed in claim 9 , wherein the combining of the first sub-amount of the top gas is with the reducing reduction gas components is performed after a treatment of the top gas.

11 . The method as claimed in claim 9 , wherein the thermal utilization comprises supplying heat to a member of a group comprising:
a reformer; a reduction gas heater; a drying apparatus for iron oxide-containing material; a heating apparatus for iron oxide-containing material; a treatment apparatus for iron oxide-containing material; and a steam or hot water generation apparatus.

12 . The method as claimed in claim 9 , wherein at least a sub-amount of the tail gas mixture is utilized in an inert gas generator.

13 . The method as claimed in claim 9 , wherein at least a sub-amount of the melting offgas is utilized in a reformer.

14 . The method as claimed in claim 9 , wherein the discharge gas is admixed with at least a sub-amount of the process-intrinsic vent gas before separating the second sub-amount of the top gas into the hydrogen-enriched gas stream and into the hydrogen-depleted tail gas stream.

15 . The method as claimed in claim 9 , wherein the thermal utilization is performed with supply of at least one fuel to the tail gas mixture.

16 . The method as claimed in claim 9 , wherein the tail gas mixture is sent to a gas storage before the thermal utilization and withdrawn from the gas storage for the thermal utilization.

17 . The method as claimed in claim 16 , wherein at least one fuel is also introduced into the gas storage.

Assignees

• Primetals Technologies Austria GmbH

Inventors

• Millner Robert
• Rein Norbert
• Wurm Johann
• Zellinger Karl-Heinz

Classifications

• C21B2100/66

  Heat exchange · CPC title

• C21B2100/40

  Gas purification of exhaust gases to be recirculated or used in other metallurgical processes · CPC title

• C21B13/0073 Primary

  Selection or treatment of the reducing gases · CPC title

• Y02P10/134

  by avoiding CO2, e.g. using hydrogen · CPC title

• C21B2100/26

  by adding additional fuel in recirculation pipes · CPC title