Quality assessment for Suitability for Ironmaking Process

Iron-containing raw materials like iron ores or pellets are the metallic feed for the Blast Furnace process. Mostly these materials consist of iron oxides which are chemically reduced inside the Blast Furnace to metallic iron. 

 

Iron Ore (in general)

The quality of the introduced iron containing burden materials is decisive for the economic efficiency of the Blast Furnace process.

There are many quality items which define the suitability of the different materials (physical,chemical and metallurgical testing methods).

  • Assessment of Iron Ore Qualities
    • Mineralogy
    • Chemical Composition
    • Grain Size distribution
    • Further Processing by Beneficiation
    • Final Product: Lump Ore, Sintering Fines, Concentrates

 

  • Suitability for Ironmaking Processes
    • Reducibility
    • Disintegration
    • Physical Strenght
    • Grain Size distribution
    • Melting Behaviour
    • Slag Formation

 

Iron Ore Fines

Nowadays most of the iron ores are available as "Fines" i.e. the range of the grain sizes of these materials lies between 0 and 10 mm.

These Iron Ore Fines represent a natural grain size distribution resulting from basic beneficiation processes like crushing, washing and screening.

Concentrates are ores which have been processed in more complicate beneficiation processses resulting in grain sizes of 0 to 1 mm approximately.

  • Concentrates
    • Mineralogy
    • Chemical Composition
    • Grain Size distribution
    • Suitability for Sintering Process
    • Suitability for Handling

 

  • Sinter Fines
    • Mineralogy
    • Chemical Composition
    • Grain Size distribution
    • Suitability for Sintering Process
    • Suitability for Handling

 

Pellets

Pellets are agglomerated iron ores which have been beneficiated in a more complicate process after being crushed very finely and the use of additives like limestone and bentonite. In a second step the pellets are calcinated in order to get a high strenght of the product. Grain size range lies normally between 6 and 20 mm.

  • Suitability for Ironmaking Process
    • Chemical Composition
    • Reducibility
    • Disintegration
    • Physical Strength
    • Grain Size distribution
    • Melting Behaviour in a Burden Mix with Winter and Lump Ore
    • Slag Formation
    • Swelling

 

Lump Ores

Lump Ores are naturally mined ores which have only been crushed and screened to a grain size appropriate to the Blast Furnace process.

The availability of lump ores today is declining because of depletion of the mineral deposits.

 

  • Suitability for Ironmaking Process
    • Chemical Composition
    • Reducibility (ISO 4692, ISO 7992)
    • Disintegration (ISO 13930, ISO 4696.2)
    • Physical Strength (ISO 3271)
    • Grain Size distribution
    • Melting Behaviour in a Burden Mix with Sinter and Lump Ore (Quality assessment for Suitability for Ironmaking Process)
    • Slag Formation (Quality assessment for Suitability for Ironmaking Process)

 

  • Other Burden Components
    • Limestone
    • Olivine, Dunite as MgO carrier