Ironmaking method

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.

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.