Ironmaking represents the first step in steelmaking.
The iron and steel industry is the most energy-intensive and capital-intensive manufacturing sector in the world (Strezov, 2006).
Steelmaking processes depend on different forms of iron as primary feed material. Traditionally, the main sources of iron for making steel were Blast Furnace hot metal and recycled steel in the form of scrap.
The Blast Furnace (BF) has remained the workhorse of worldwide virgin iron production (i.e., hot metal) for more than 200 years. Over the years, BFs have evolved into highly efficient chemical reactors, capable of providing stable operation with a wide range of feed materials.
However, operation of modern efficient BFs normally involves sintering and coke making and their associated environmental problems.
More than 90% of iron is currently produced via the BF process, while the rest is coming from Direct Reduction (DR) processes, Mini Blast Furnaces (MBFs), Corex, Finex, Ausmelt, etc. Additionally, the severe shortage of good-quality metallurgical coal has remained an additional constraint all over the world. In view of this, there is an increasing awareness that the BF route needs to be supplemented with alternative ironmaking processes that are more environment friendly and less dependent on metallurgical coal.
1. Dr. Hassan Z. Harraz
hharraz2006@yahoo.com
Autum 2023
“Iron Ore is more Integral to the Global
Economy than any Other Commodity,
Except Perhaps Oil”.
Christopher LaFemina, mining analyst at Barclays Capital
(In 2011 the Financial Times quoted)
@Hassan Harraz 2023
IRONMAKING
IRON PRODUCTION
(IRONWORKS)
DOI: 10.13140/RG.2.2.32002.45767
6. Table 1: Ironmaking Processes
IRON
PRODUCTION
(IRONWORKS)
Smelting
• Blast Furnace (produces Pig Iron)
o Cold blast
o Hot blast
o Anthracite iron
• Direct Reduction Furnace (produces DRI)
• Bloomery (produces Sponge Iron)
Secondary
• Wrought Iron (via Finery Forge or
Reverberatory Puddling Furnace)
• Cast Iron (via Cupola Furnace or Induction
Furnace)
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IRONMAKING
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16. Reforming natural gas has a H2/CO ratio of 1.6, the temperature is 900 C. Part of the exhaust gas is mixed
with natural gas and reformed, and the remainder is used as the fuel for the reformer furnace. Higher
furnace temperatures result in higher productivity, because the metal is reduced by an endothermic
reaction. However, an excessive furnace temperature will cause the pellets and lump ore to melt during
reduction and agglomeration. The maximum reduction rate is about 95%, and the carbon content is limited
to about 2.5%.
Example of Direct Reduction Process
@Hassan Harraz 2023
IRONMAKING
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18. References
1. "What is direct reduced iron (DRI)? definition and meaning". Businessdictionary.com.
Retrieved 2011-07-11.
2. "Direct reduced iron (DRI)". International Iron Metallics Association. 14 November 2019.
3. R. J. Fruehan, et al. (2000). Theoretical Minimum Energies to Produce Steel (for
Selected Conditions)
4. "2020 World Direct Reduction Statistics" (PDF). Midrex Technologies. 2020. Retrieved 25
January 2020.
5. "Steel making today and tomorrow". Archived from the original on 20 December 2020.
6. Direct Reduced Iron (DRI) - Cargo Handbook - the world's largest cargo transport
guidelines website". www.cargohandbook.com. Retrieved 2022-06-18.
7. Hattwig, Martin; Steen, Henrikus (2004), Handbook of explosion prevention and
protection, Wiley-VCH, pp. 269–270, ISBN 978-3-527-30718-0. (dead link 24
October 2019).
8. "MIDREX" (PDF).
9. Zimmermann, Michael B.; Winichagoon, Pattanee; Gowachirapant, Sueppong; Hess,
Sonja Y.; Harrington, Mary; Chavasit, Visith; Lynch, Sean R.; Hurrell, Richard F.
(2005). "Comparison of the efficacy of wheat-based snacks fortified with ferrous
sulfate, electrolytic iron, or hydrogen-reduced elemental iron: Randomized, double-
blind, controlled trial in Thai women". The American Journal of Clinical
Nutrition. 82 (6): 1276–1282. doi:10.1093/ajcn/82.6.1276. PMID 16332661.
10. Shah, Bhagwan G.; Giroux, Alexandre; Belonje, Bartholomeus (1977). "Specifications
for reduced iron as a food additive". Journal of Agricultural and Food
Chemistry. 25 (3): 592–594. doi:10.1021/jf60211a044. PMID 858856.
@Hassan Harraz 2023
IRONMAKING
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