Method and device for direct reduction with dry vent gas de-dusting

Patent metadata

Field	Value
Publication number	US-2020332377-A1
Application number	US-201716305926-A
Country	US
Kind code	A1
Filing date	Jun 8, 2017
Priority date	Jun 9, 2016
Publication date	Oct 22, 2020
Grant date	—

Abstract

A method for direct reduction of metal oxide-containing starting materials to produce metallized material by contact with hot reduction gas in a reduction unit (1), wherein the product of the direct reduction is discharged from the reduction unit (1) by means of a product discharge device (3) which is flushed with seal gas and from which vent gas is drawn and subsequently de-dusted. The vent gas is de-dusted dry and the content of at least one gaseous constituent is reduced by catalytic conversion or combustion. Also, a device for carrying out the method is disclosed.

First claim

1 . A method for direct reduction of metal oxide-containing, to iron oxide-containing, starting materials to produce metallized material comprising:
contacting the starting materials with hot reduction gas in a reduction unit; discharging the product of the direct reduction from the reduction unit by means of a product discharge device, by flushing the product discharge device with seal gas and drawing vent gas from the discharge device and subsequently, de-dusting the vent gas; wherein the vent gas is de-dusted dry, the content of at least one gaseous constituent of the de-dusted vent gas is reduced, wherein the content of the at least one gaseous constituent is reduced by conversion into CO 2 and/or into H 2 O by at least one of catalytic conversion using at least one of oxygen O 2 and/or H 2 O in the form of steam,
and/or
by combustion.

2 . The method as claimed in claim 1 , wherein the gaseous constituent is carbon monoxide CO,
and the content the CO 2 is reduced by conversion into CO 2 by at least one of catalytic conversion using oxygen O 2 and/or H 2 O in the form of steam,
and/or
by combustion.

3 . The method as claimed in claim 1 claim 1 , wherein the at least one of oxygen-containing and/or steam-containing gases are supplied for the conversion into CO 2 and/or H 2 O.

4 . A device for carrying out a method as claimed in claim 1 comprising:
a reduction unit with a reduction gas supply;
a product discharge device, from the reduction unit;
a seal gas supply line opening into the product discharge device;
a vent gas removal line exiting from the product discharge device;
a dry de-dusting device, the vent gas removal line opening into the dry de-dusting device a diverting device exiting from the dry de-dusting device for diverting dry de-dusted vent gas into the atmosphere;
the diverting device comprising a reducing device for reducing the content of at least one gaseous constituent of the de-dusted vent gas, the reducing device reducing the content by
catalytic conversion to at least one of CO 2 and/or H 2 O using at least one of oxygen O 2 and/or H 2 O in the form of steam,

and/or
by combustion to at least one of CO 2 and/or H 2 O.

5 . The device as claimed in claim 4 , further comprising:
the device for reducing the content of at least one gaseous constituent of the de-dusted vent gas is a device for reducing the CO content by catalytic conversion to CO 2 using oxygen O 2 and/or H 2 O in the form of steam,
and/or
by combustion to CO 2 .

6 . The device as claimed in claim 5 , the device for reducing the content of at least one gaseous constituent of the de-dusted vent gas, preferably the CO content, has at least one supply line for supplying oxygen-containing and/or steam-containing gases.

Assignees

• Primetals Technologies Austria GmbH

Inventors

• Eder Thomas
• Millner Robert

Classifications

• F27D17/20

  Arrangements for treatment or cleaning of waste gases · CPC title

• Y02P10/134

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

• F27D17/22

  for removing solid constituents · CPC title

• F27B1/21

  Arrangements of devices for discharging · CPC title

• F27D17/00

  Arrangements for using waste heat; Arrangements for using, or disposing of, waste gases · CPC title