A Review of Beneficiation Practices in the United States Iron Ore Industry

In 2022, the U.S. iron ore industry produced 46 Mt of iron ore concentrate, primarily driven by the Mesabi and Marquette Ranges in Minnesota and Michigan, respectively. Notably, seven processing facilities contributed 98% of usable iron ore. The iron ores in the US are highly variable in mineralogy, necessitating tailored processing strategies for each type. This paper provides a detailed overview of the evolution, challenges, and opportunities for the iron ore industry in the U.S. A detailed review and comparison of the mineralogy, and beneficiation strategies for the different iron ores in the U.S. is also presented. Processing methodologies have evolved from direct shipping of high-grade iron ores to complex beneficiation flowsheets to process low-grade, mineralogically complex iron ores, with oxidized magnetite, goethite, and siderite. The challenges associated with the declining ore grades, mineralogically complex ores and stringent environmental regulations have pushed the iron ore industry to seek sustainable processes and technologies such as fine processing, selective flocculation, and flotation along with dewatering options. The success of the future iron ore industry hinges on historical tailings and mine overburden reprocessing, the adoption of emerging and sustainable technologies to not only improve energy, water, and metallurgical efficiencies, but also produce high-quality concentrate for advanced iron-making techniques, such as hydrogen direct reduction and direct smelting.