The document discusses reduction roasting followed by magnetic separation as a promising technique for enriching iron values from low-grade iron ores. It provides an overview of the technique, noting that reduction roasting involves reducing hematite and goethite phases in iron ores to magnetite, which can then be separated magnetically. The document reviews reduction roasting studies on various types of low-grade iron ores, including oolitic iron ores, banded iron ores, iron ore slimes and tailings. Emerging trends in reduction roasting such as microwave-assisted and biomass-assisted methods are also examined.

1. Dr. Hassan Z. Harraz
hharraz2006@yahoo.com
Autum 2023
@Hassan Harraz 2023
Enrichment of Fe by Reduction Roasting-Magnetic Separation
Enrichment Iron Values OF Low-grade
Iron Ore Resources
Using
Reduction Roasting-Magnetic
Separation Techniques -a review

2. Abstract
❑ Because of the rapid depletion of easily processed iron ores, the utilization of refractory ores has
attracted increasing attention .
❑ There several billion tonnes iron deposits, and most are refractory ores, which are difficult to
process by conventional methods because of the low iron grade, fine grain size and complex
mineralogy.
➢ The beneficiation of low-grade iron ores to meet the growing demand for iron and steel is
an important research topic.
➢ At present, magnetization roasting followed by magnetic separation is one of the most
effective technologies for the beneficiation of refractory iron ores.
❑ However, certain ores do not qualify to be treated in physical separation processes, and hence,
alternative strategies are being looked into for upgrading their iron content.
➢ Reduction roasting has many advantages over the physical beneficiation process, such as
enhanced iron recovery and processing of complex and poorly liberated iron ores.
❑ The objective of this presentation is to compile and amalgamate the crucial information regarding
the beneficiation of low-grade iron ores using carbothermic reduction followed by magnetic
separation, which is a promising technique to treat iron ores with complex mineralogy and
liberation issues.
❑ Reduction roasting studies done for different types low-grade iron ores including oolitic iron ores,
banded iron ores, iron ore slimes and tailings, and industrial wastes have been discussed.
❑ Reduction roasting followed by magnetic separation is a promising method to recover the iron
values from low-grade iron ores.
➢ The process involves the reduction of the goethite and hematite phases to magnetite,
which can subsequently be recovered using a low-intensity magnetic separation unit.
❑ The large-scale technological advancements in reduction roasting and the possibilities of the
application of alternative reductants as substitutes for coal have also been highlighted.
@Hassan Harraz 2023
Enrichment of Fe by Reduction Roasting-Magnetic Separation
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3. Contents
1. INTRODUCTION
2. REDUCTION ROASTING AND MAGNETIC SEPARATION
2.1. Oolitic iron ores
2.2. Goethitic and limonitic ores
2.3. Iron ore fines and tailings
2.4. Other low-grade iron ore resources
2.5. Other resources
3. EMERGING TRENDS IN REDUCTION ROASTING
3.1. Microwave-assisted reduction roasting
3.2. Biomass as reductants
3.3. Self-magnetizing roasting
4. LARGE SCALE STUDIES OF REDUCTION ROASTING TECHNIQUE
5. CONCLUDING REMARKS
6. REFERENCES
@Hassan Harraz 2023
Enrichment of Fe by Reduction Roasting-Magnetic Separation
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4. Keywords:
•Low-grade iron ore
•Beneficiation
•Reduction roasting
•Microwave
•Magnetization Roasting
•Magnetic Separation
•Refractory Iron Ores.
@Hassan Harraz 2023
Enrichment of Fe by Reduction Roasting-Magnetic Separation
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5. Objective
❑The objective of the present communication is,
➢ to investigate and summarize the related literature
papers on reduction roasting-magnetic separation of low-
grade iron ore resources.
➢It is anticipated that summarizing the knowledge and
experience on this topic would help the research
community to work further in the appropriate direction
towards the commercialization of the process.
@Hassan Harraz 2023
Enrichment of Fe by Reduction Roasting-Magnetic Separation
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@Hassan Harraz 2023
Enrichment of Fe by Reduction Roasting-Magnetic Separation
41
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