A Critical Review on the Magnetization Roasting of Low/Lean-Grade Iron Ore Resources Using Renewable/Non-Renewable Reductant: An Approach Towards Iron ore Sustainability

Abstract

Iron ores are naturally occurring, non-renewable, limited, and are vital raw materials for iron and steel-making companies. In China and India, production has expanded significantly in recent years and is predicted to touch 2600 million tonnes (MT) or more in 2030. Approximately 650 million tonnes of scrap per annum (MTPA) can be recycled to meet the iron demand. Moreover, fresh iron ore will be required to compensate for the remaining 3200 MTPA, significantly increasing the need for iron ore resources. However, long-term mining ultimately deteriorated the quality of iron ore deposits worldwide, and the existing mines are facing challenges in supplying high-grade iron values using crushing and screening. Thus, receiving the right quality iron ore in lump or pellet/sinter form is a concern for steel industries, leading to a strong desire to recover the iron value of the ore during the preparation of raw material by a physical beneficiation or magnetization roasting route followed by a magnetic separation process. This paper critically reviews the challenges and methodology to recover iron values by beneficiation using lower-grade iron ore resources. Moreover, the opportunities lying in the magnetization roasting process for different mineralogical behaviors of iron ore such as banded iron ores, low-grade high LOI iron ores, iron ore upgradation plant tailings, and oolitic iron ores using fossil fuel and biomass reductant to generate synthesized magnetite pellet feed concentrate were discussed. A comprehensive review of the beneficiation practices visualizing the importance of feed ore mineralogy and the reductant used on the operating parameters and process to be chosen was summarized.