Ironmaking method

Patent metadata

Field	Value
Publication number	US-2024384364-A1
Application number	US-202218693787-A
Country	US
Kind code	A1
Filing date	Sep 29, 2022
Priority date	Sep 29, 2021
Publication date	Nov 21, 2024
Grant date	—

Abstract

An ironmaking method includes ore beneficiating a high combined water content iron ore including a loss of ignition of 3 to 12 mass % into a goethite-rich part including at least a loss of ignition of 4 mass % or more and an iron content of 55 mass % or more; agglomerating the goethite-rich part into first fired pellets in a pellet induration furnace; and the first fired pellets into a shaft furnace while the first fired pellets have a surface temperature of 600° C. or higher, and directly reducing the first fired pellets using a reducing gas containing 60 volume % or more of hydrogen.

First claim

1 . An ironmaking method, comprising:
a high combined water content iron ore including a loss of ignition of 3 to 12 mass % into a goethite-rich part including at least a loss of ignition of 4 mass % or more and an iron content of 55 mass % or more; the goethite-rich part into first fired pellets in a pellet induration furnace; and charging the first fired pellets into a shaft furnace while the first fired pellets have a surface temperature of 600° C. or higher, and directly reducing the first fired pellets using a reducing gas containing 60 volume % or more of hydrogen.

2 . The ironmaking method according to claim 1 ,
wherein, in the directly reducing, the first fired pellets are directly reduced to a metallization degree of 60% to 95%.

3 . The ironmaking method according to claim 1 , further comprising:
a hematite-rich part into second fired pellets in a pellet induration furnace, wherein, in the ore beneficiating, the hematite-rich part including a loss of ignition of less than 4 mass % and an iron content of 55 mass % or more is additionally beneficiated.

4 . The ironmaking method according to claim 3 , further comprising:
the second fired pellets in a shaft furnace using a reducing gas containing 60 volume % or more of hydrogen to produce direct reduction iron including a metallization degree of 90% or more.

5 . The ironmaking method according to claim 1 , further comprising:
tailings from the high combined water content iron ore before the ore beneficiating.

6 . The ironmaking method according to claim 2 , further comprising:
removing tailings from the high combined water content iron ore before the ore beneficiating.

7 . The ironmaking method according to claim 3 , further comprising:
removing tailings from the high combined water content iron ore before the ore beneficiating.

8 . The ironmaking method according to claim 4 , further comprising:
removing tailings from the high combined water content iron ore before the ore beneficiating.

9 . An ironmaking method, comprising:
an ore beneficiation step in which a high combined water content iron ore including a loss of ignition of 3 to 12 mass % is beneficiated into a goethite-rich part including at least a loss of ignition of 4 mass % or more and an iron content of 55 mass % or more; a first agglomeration processing step in which the goethite-rich part is agglomerated into first fired pellets in a pellet induration furnace; and a first reduction step in which the first fired pellets are charged into a shaft furnace while the first fired pellets have a surface temperature of 600° C. or higher, and directly reduced using a reducing gas containing 60 volume % or more of hydrogen.

Assignees

• Nippon Steel Corp

Inventors

• Mizutani Moritoshi

Classifications

• C22B1/20

  in sintering machines with movable grates · CPC title

• C22B1/2406

  pelletizing · CPC title

• C22B1/214

  in shaft furnaces · CPC title

• C21B13/14

  Multi-stage processes {processes carried out in different vessels or furnaces} · CPC title

• C21B13/02

  in shaft furnaces · CPC title