A major part of the project focused on understanding the economic potential of the new technologies being developed. HARARE showed that the processing routes for bauxite residue could create valuable products such as alumina, iron, and even scandium. However, the profitability of these processes turned out to be more challenging than expected. High energy prices and the cost of hydrogen in particular place a heavy burden on the economics. Some routes, especially those involving scandium recovery, require significant redesign before they can realistically become commercial. In contrast, the copper slag route appears more promising economically, although uncertainties remain due to the lack of full pilot scale data.
If the most optimistic economic scenarios are realised, the project estimates that hundreds of new jobs could be created at processing sites in Greece and Germany, with additional benefits for equipment suppliers, alumina producers, and industries that rely on iron, copper, nickel, or other recovered materials. The technologies developed in HARARE rely largely on existing industrial equipment, making scale up more feasible.
From a resource perspective, HARARE showed that very large quantities of valuable materials could be recovered annually if the processes were implemented at full scale. These include significant amounts of alumina, iron products, slag that can be used in cement, and other metals such as copper and nickel. Because these materials can then circulate within Europe’s industrial system, the project contributes directly to a more circular and self reliant European economy.
Environmental performance was another major area of evaluation. By replacing fossil fuels with renewable hydrogen and by recovering more resources from waste, HARARE’s processes offer substantial reductions in greenhouse gas emissions. In particular, the bauxite residue routes involving smelting or sodium based leaching emit considerably less CO2 than today’s standard alumina production methods. The copper slag routes also perform well, especially due to the benefits of replacing clinker in cement production, which is normally very emission intensive.
The project’s work also extended to health and safety, where guidelines for the safe use of hydrogen in laboratories and pilot plants were published openly for others to use.