Process and apparatus for direct reduction with electrically heated-up reduction gas

Patent metadata

Field	Value
Publication number	US-12209293-B2
Application number	US-201917414368-A
Country	US
Kind code	B2
Filing date	Dec 16, 2019
Priority date	Dec 17, 2018
Publication date	Jan 28, 2025
Grant date	Jan 28, 2025

Abstract

A method of direct reduction of metal oxides that includes catalytic reforming of hydrocarbonaceous gas in a reformer to obtain reformer gas, obtaining at least one precursor gas based on the reformer gas, preparing a reduction gas by heating the at least one precursor gas by means of electrical energy, at least a portion of the electrical energy being introduced by means of plasma.

First claim

The invention claimed is:

1. A method of direct reduction of metal oxides with a reduction gas, comprising:
catalytic reforming of hydrocarbonaceous gas in a reformer to obtain reformer gas, the reformer gas exiting the reformer at a first temperature,
producing at least one precursor gas based on the reformer gas, and
preparing the reduction gas by heating the at least one precursor gas to a second temperature above the first temperature by means of electrical energy
wherein at least a portion of the electrical energy is introduced by means of plasma.

2. The method as claimed in claim 1 , wherein the second temperature is no more than 200° C. above the first temperature.

3. The method as claimed in claim 2 , wherein the at least one precursor gas envisaged for electrical heating, prior to the heating by means of the electrical energy, is already heated in another way to at least 700° C.

4. The method as claimed in claim 3 , wherein the at least one precursor gas envisaged for the electrical heating is heated by means of the electrical energy to more than 800° C.

5. The method as claimed in claim 1 , wherein on introduction of the reduction gas into a reduction unit containing the metal oxides to be reduced, the temperature of the reduction gas is in the range of 800° C. to 1100° C.

6. The method as claimed in claim 1 , further comprising directly reducing metal oxides using at least one additional reduction gas.

7. The method as claimed in claim 1 , further comprising heating one or more further precursor gases, by means of electrical energy.

8. The method as claimed in claim 7 , further comprising adding hydrocarbonaceous additional gas to the further precursor gas which is heated by means of electrical energy.

9. The method as claimed in claim 8 , further comprising reforming at least a portion of the hydrocarbonaceous additional gas in situ before the reduction gas is introduced into a reduction unit containing the metal oxides.

10. The method as claimed in claim 7 , wherein the one or more further precursor gases comprises the at least one precursor gas or another precursor gas.

Assignees

• Primetals Technologies Austria GmbH

Inventors

• Hauzenberger Franz
• Millner Robert
• Ofner Hanspeter
• Rein Norbert
• Rosenfellner Gerald
• Wurm Johann

Classifications

• C21B13/12

  in electric furnaces · CPC title

• C21B13/0073 Primary

  Selection or treatment of the reducing gases · CPC title

• C21B2100/22

  by reforming · CPC title

• Y02P10/143

  of methane [CH4] · CPC title

• Y02P10/134

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