Economics of Electrowinning Iron from Ore for Green Steel Production

The transition to green steel production is pivotal for reducing global carbon emissions. This study presents a comprehensive techno-economic analysis of various green steel production methods, including hydrogen reduction and three different electrolysis techniques: aqueous hydroxide electrolysis (AHE), molten salt electrolysis, and molten oxide electrolysis (MOE). By comparing process flow diagrams, capital and operational expenditures, specific energy consumption, and production footprint, this work provides a high-level assessment of the economic viability of these processes as they mature. The analysis reveals that MOE, despite its ongoing development, offers a promising route for iron production given its ability to process a wide range of ore qualities and the potential to sell electrolyte as a cement product. However, the best balance between deployment ready technology and economic benefit is AHE. Operational challenges are also discussed, such as electrolyte loss and slag handling. We suggest that the sale of by-products like oxygen may not significantly impact the economics due to market saturation. The findings underscore the importance of continued research and development in process optimization to realize the full potential of green steel technologies. All the calculations have been released as supplementary electronic material (MS Excel workbook). The format has been inspired by the techno-economic assessment template (TECHTEST) distributed by the US Dept. of Energy.

Graphical Abstract