7
the context of improving the environmental friendliness of
steelmaking.
Blast furnace smelting of iron ore could safely be said
to be one of the oldest industrial processes, with the associ-
ated centuries of refinements and optimizations. The scale,
both in terms of time requirements and material resource
requirements of effectively designing and operating a blast
furnace in the modern day are very considerable. The most
major optimizations that remain which can be addressed by
an iron ore concentrator are those which are required of the
final agglomerate product in the first place. The advantages
of the blast furnace process are primarily the tremendous
capacity provided and the considerable proven history of
the process to provide a consistent reduced iron product.
Especially given a high quality and consistent feed for the
blast furnaces, it is perhaps rather unlikely that any alterna-
tive process will find itself economically competitive with
blast furnace operations.
Of course, that is also exactly the reason why alter-
native processes exist: high quality and consistent feeds,
as required by the blast furnaces, are not always available
– even if high grade iron sources are available, there may
be various impurities or practical difficulties involved the
material that suggest that alternative processes be used
instead. Additionally, not all iron ore sources which are
worth exploiting (e.g., perhaps due to co-located minerals
of other elements, or iron rich tailings from the processing
of other materials) are conveniently located to efficiently
ship material to blast furnaces.
Most of the new opportunities in the iron ore reduc-
tion process are thus primarily to be found in faster mov-
ing, smaller scale, and more flexible alternatives to blast
furnace processing, and likely to process otherwise difficult
iron sources.
One such process is the iron nugget process (Anameric
and Kawatra, 2006 Anameric et al., 2006 Archambo and
Kawatra, 2021a). This is essentially an alternative to blast
furnace processing in which lump agglomerated materials
are mixed with a reducing agent and fired directly, creating
mixed nuggets consisting of metallic iron and the separated
slag. Similar to blast furnace processing, many impurities
can be removed into the slag phase, which in turn tends to
physically separate from the metallic iron product. Unlike
blast furnace processing, the metallic iron product is pro-
duced in relatively small nuggets rather than as a large casted
product or as molten metal. The resulting iron product is
typically pig iron suitable for further refining into steel.
This process has been shown on a laboratory scale to
be able to effectively process even very difficult iron-bear-
ing materials such as Bayer process red mud (Archambo
and Kawatra, 2021a), which is otherwise very difficult to
upgrade using mineral processing techniques.
SUMMARY
The process of transforming various iron resources, espe-
cially the most important iron ore minerals, into metal-
lic iron and workable steel products is a vital technology
for the continuation of everyday living. For the relatively
low-grade ores mined in the United States and around the
world in several locations today, the overall process follows
the fundamental steps of mineral processing directly into
the steps required to prepare a high quality feed stock for
the reduction of the iron ore.
Each of these steps presents unique opportunities both
to further our understanding of the iron ore concentration
process and to improve our productivity and effective use of
resources. These opportunities, if approached and exploited,
should help maintain these technologies to ensure the avail-
ability of our iron resources into the far future, as they allow
for the processing of the vast reserves of lower grade iron
deposits along with improved recycling of iron materials
from other sources.
REFERENCES
Anameric, B., and Kawatra, S.K. (2006). “Laboratory
study related to the production and properties of pig
iron nuggets,” Mining, Metallurgy &Exploration, 23,
pp. 52–56.
Anameric, B., Rundman, K.B., and Kawatra, S.K. (2006).
“Carburization effects on pig iron nugget making,”
Mining, Metallurgy &Exploration, 23, pp. 139–150.
Araujo, A.C., Viana, P.R.M., and Peres, A.E.C., “Reagents
in iron ores flotations,” Minerals Engineering, 18(2),
pp. 219–224.
Archambo, M., and Kawatra, S.K., (2021a). “Utilization
of Bauxite Residue: Recovering Iron Values Using the
Iron Nugget Process,” Mineral Processing and Extractive
Metallurgy Review, 42(4), pp. 222–230.
Archambo, M., and Kawatra, S.K., (2021b). “Red mud:
Fundamentals and new avenues for utilization,”
Mineral Processing and Extractive Metallurgy Review,
42(7), pp. 427–450.
Campos, T.M., Bueno, G., Barrios, G.K.P., and
Tavares, L.M., (2019). “Pressing iron ore concentrate
in a pilot-scale HPGR. Part 1: Experimental results,”
Minerals Engineering, 140, pg. 105875.
Carlson, J.J., and Kawatra, S.K., 2011. “Effects of CO2 on
the zeta potential of hematite,” International Journal of
Mineral Processing, 98(1–2), pp. 8–14.
the context of improving the environmental friendliness of
steelmaking.
Blast furnace smelting of iron ore could safely be said
to be one of the oldest industrial processes, with the associ-
ated centuries of refinements and optimizations. The scale,
both in terms of time requirements and material resource
requirements of effectively designing and operating a blast
furnace in the modern day are very considerable. The most
major optimizations that remain which can be addressed by
an iron ore concentrator are those which are required of the
final agglomerate product in the first place. The advantages
of the blast furnace process are primarily the tremendous
capacity provided and the considerable proven history of
the process to provide a consistent reduced iron product.
Especially given a high quality and consistent feed for the
blast furnaces, it is perhaps rather unlikely that any alterna-
tive process will find itself economically competitive with
blast furnace operations.
Of course, that is also exactly the reason why alter-
native processes exist: high quality and consistent feeds,
as required by the blast furnaces, are not always available
– even if high grade iron sources are available, there may
be various impurities or practical difficulties involved the
material that suggest that alternative processes be used
instead. Additionally, not all iron ore sources which are
worth exploiting (e.g., perhaps due to co-located minerals
of other elements, or iron rich tailings from the processing
of other materials) are conveniently located to efficiently
ship material to blast furnaces.
Most of the new opportunities in the iron ore reduc-
tion process are thus primarily to be found in faster mov-
ing, smaller scale, and more flexible alternatives to blast
furnace processing, and likely to process otherwise difficult
iron sources.
One such process is the iron nugget process (Anameric
and Kawatra, 2006 Anameric et al., 2006 Archambo and
Kawatra, 2021a). This is essentially an alternative to blast
furnace processing in which lump agglomerated materials
are mixed with a reducing agent and fired directly, creating
mixed nuggets consisting of metallic iron and the separated
slag. Similar to blast furnace processing, many impurities
can be removed into the slag phase, which in turn tends to
physically separate from the metallic iron product. Unlike
blast furnace processing, the metallic iron product is pro-
duced in relatively small nuggets rather than as a large casted
product or as molten metal. The resulting iron product is
typically pig iron suitable for further refining into steel.
This process has been shown on a laboratory scale to
be able to effectively process even very difficult iron-bear-
ing materials such as Bayer process red mud (Archambo
and Kawatra, 2021a), which is otherwise very difficult to
upgrade using mineral processing techniques.
SUMMARY
The process of transforming various iron resources, espe-
cially the most important iron ore minerals, into metal-
lic iron and workable steel products is a vital technology
for the continuation of everyday living. For the relatively
low-grade ores mined in the United States and around the
world in several locations today, the overall process follows
the fundamental steps of mineral processing directly into
the steps required to prepare a high quality feed stock for
the reduction of the iron ore.
Each of these steps presents unique opportunities both
to further our understanding of the iron ore concentration
process and to improve our productivity and effective use of
resources. These opportunities, if approached and exploited,
should help maintain these technologies to ensure the avail-
ability of our iron resources into the far future, as they allow
for the processing of the vast reserves of lower grade iron
deposits along with improved recycling of iron materials
from other sources.
REFERENCES
Anameric, B., and Kawatra, S.K. (2006). “Laboratory
study related to the production and properties of pig
iron nuggets,” Mining, Metallurgy &Exploration, 23,
pp. 52–56.
Anameric, B., Rundman, K.B., and Kawatra, S.K. (2006).
“Carburization effects on pig iron nugget making,”
Mining, Metallurgy &Exploration, 23, pp. 139–150.
Araujo, A.C., Viana, P.R.M., and Peres, A.E.C., “Reagents
in iron ores flotations,” Minerals Engineering, 18(2),
pp. 219–224.
Archambo, M., and Kawatra, S.K., (2021a). “Utilization
of Bauxite Residue: Recovering Iron Values Using the
Iron Nugget Process,” Mineral Processing and Extractive
Metallurgy Review, 42(4), pp. 222–230.
Archambo, M., and Kawatra, S.K., (2021b). “Red mud:
Fundamentals and new avenues for utilization,”
Mineral Processing and Extractive Metallurgy Review,
42(7), pp. 427–450.
Campos, T.M., Bueno, G., Barrios, G.K.P., and
Tavares, L.M., (2019). “Pressing iron ore concentrate
in a pilot-scale HPGR. Part 1: Experimental results,”
Minerals Engineering, 140, pg. 105875.
Carlson, J.J., and Kawatra, S.K., 2011. “Effects of CO2 on
the zeta potential of hematite,” International Journal of
Mineral Processing, 98(1–2), pp. 8–14.