Reformer-gas-based reduction process with decarbonization of the fuel gas for the reformer

Patent metadata

Field	Value
Publication number	US-9797026-B2
Application number	US-201514811037-A
Country	US
Kind code	B2
Filing date	Jul 28, 2015
Priority date	Jul 31, 2009
Publication date	Oct 24, 2017
Grant date	Oct 24, 2017

Abstract

In a process and apparatus for the reduction of metal oxides to form metalized material by contact with hot reducing gas, which is produced at least partially by catalytic reformation of a mixture of—a gas containing carbon dioxide (CO 2 ) and/or steam (H 2 O) with—gaseous hydrocarbons, the fuel gas for burners which provide the heat for the endothermal reformation processes which take place during the reformation is obtained at least partially from a partial quantity of the top gas produced during the reduction of metal oxides to form metalized material, wherein this partial quantity of the top gas, before it is used as a component of the fuel gas, is firstly subjected to dedusting and then to a CO conversion reaction, and the conversion gas obtained during the CO conversion reaction is subjected to CO 2 removal after cooling.

First claim

What is claimed is:

1. An apparatus comprising:
a reduction unit for the reduction of metal oxides to form metalized material, the reduction unit having a discharge line for discharging top gas from the reduction unit,
a reformer that carries out catalytic reformation of a mixture of gas containing at least one of carbon dioxide and steam with gaseous hydrocarbons,
wherein the reformer is provided with a mixture supply line for supplying the mixture of gas, and wherein the reformer is provided with burners, which are connected to an oxygen supply line, the burners providing heat for the catalytic reformation by combustion of a fuel gas and oxygen supplied by the supply line,
the reformer having a drawing-off line for drawing off combustion off-gas from the reformer, and
the reformer having a reducing gas supply line for providing hot reducing gas from the reformer into the reduction unit, the drawing-off line and the reducing gas supply line being different lines,
wherein the burners are connected to the discharge line via a connection line which branches off from the discharge line, and
wherein a dedusting apparatus is present either in the discharge line, between the reduction unit and the connection line, or in the connection line itself, and
wherein the following devices are positioned between the dedusting device and the burners, in sequence: a CO conversion reactor, a gas cooling apparatus, and a CO 2 removal apparatus.

2. The apparatus according to claim 1 , wherein a hydrocarbon feed line for gaseous hydrocarbons issues into the connection line.

3. The apparatus according to claim 2 , wherein the hydrocarbon feed line for gaseous hydrocarbons issues into the connection line downstream from the CO 2 removal apparatus.

4. The apparatus according to claim 1 , wherein the dedusting apparatus is a dry-dedusting apparatus.

5. The apparatus according to claim 1 , wherein the dedusting apparatus is a wet-dedusting apparatus.

6. The apparatus according to claim 5 , wherein a gas heating apparatus is present in the connection line between the wet-dedusting apparatus and the CO conversion reactor.

7. The apparatus according to claim 1 , wherein the reduction unit is a fluidized bed cascade.

8. The apparatus according to claim 1 , wherein the reduction unit is a fixed-bed reduction shaft.

9. A system for the reduction of metal oxides to form metalized material by contact with a reducing gas in a reduction unit, wherein the reducing gas is produced at least partially by catalytic reformation, in a reformer, of a mixture of gas containing at least one of carbon dioxide and steam with gaseous hydrocarbons, and the reducing gas is supplied from the reformer to the reduction unit via a reducing gas supply line, the system comprising:
a burner that combusts a fuel gas to provide at least part of the heat for the endothermal reformation processes which take place during the catalytic reformation in the reformer, and
a drawing-off line for drawing off the combustion off-gas produced by the burner for the endothermal reformation processes, the drawing-off line and the reducing gas supply line being different lines,
wherein the system is configured to obtain fuel gas at least partially from a partial quantity of the top gas produced during the reduction of metal oxides to form metalized material,
wherein the system is further configured to subject the partial quantity of the top gas, from which the fuel gas is obtained, firstly to dedusting and then to a CO conversion reaction in a CO conversion reactor to obtain conversion gas, and to subject the conversion gas obtained during the CO conversion reaction to CO 2 removal after cooling to obtain CO 2 -depleted conversion gas, and to use the CO 2 -depleted conversion gas produced in the process at least as a component of the fuel gas, the CO conversion reactor being located within the system to receive top gas from the reduction unit.

10. The system according to claim 9 , wherein the system includes a reduction unit and the gas containing at least one of carbon dioxide and steam is top gas from the reduction unit.

11. The system according to claim 9 , wherein the system includes a smelting reduction unit and the gas containing at least one of carbon dioxide and steam is export gas from the smelting reduction unit, or the system includes a coal gasification unit and the gas containing at least one of carbon dioxide and steam is syngas from the coal gasification unit.

12. The system according to claim 9 , wherein gaseous hydrocarbons are admixed to the CO 2 -depleted conversion gas in order to obtain fuel gas.

13. The system according to claim 9 , wherein the dedusting takes place in dry form.

14. The system according to claim 9 , wherein the dedusting takes place in wet form.

Assignees

• Primetals Technologies Austria GmbH

Inventors

• Millner Robert
• Peer Guenter

Classifications

• C22B5/12 Primary

  by gases · CPC title

• C21B2100/282

  of carbon dioxide · CPC title

• C21B2100/44

  Removing particles, e.g. by scrubbing, dedusting · CPC title

• C21B13/00 Primary

  Making spongy iron or liquid steel, by direct processes · CPC title

• C21B13/02

  in shaft furnaces · CPC title