Periodic Reporting for period 3 - HARARE (Hydrogen As the Reducing Agent in the REcovery of metals and minerals from metallurgical waste)
Período documentado: 2024-06-01 hasta 2025-11-30
The HARARE project is a consortium aiming to demonstrate sustainable methods for producing non-ferrous metals by using hydrogen to remove waste and valorise materials in carbon-free processes. The metallurgical sector is vital to a sustainable future as vast amounts of metals, such as steel, aluminum, and copper are required for solar panels, wind turbines, electrification of transport and upgrading of the electricity grid. However, the metallurgical industry is also one of the largest CO2 emitting sectors, and Europe imports a significant amount of metal produced with carbon-based processes.
To tackle these challenges, HARARE aims to make the metallurgical industry more sustainable by implementing a circular concept based on two strategies. The first strategy involves recovering waste materials such as flash smelter slag from primary copper production and bauxite residue from aluminum production, which are typically disposed of as waste, creating environmental issues. By using hydrogen instead of carbon as a reductant, the industry can become free of CO2-emissions and decrease its dependence on hard coal imports.
HARARE's initiative is important for creating a less carbon-dependent metallurgical industry necessary for a sustainable future. The use of hydrogen-based processes offers a promising avenue for decarbonizing the sector, reducing greenhouse gas emissions, and increasing energy efficiency, thereby contributing to sustainable development goals. Additionally, HARARE's approach can have a significant impact on the economy, as the metallurgical sector is a significant contributor to Europe's economy, with over 300,000 people employed in the EU alone. By reducing energy costs and becoming more sustainable, the sector can increase its competitiveness in the face of intense competition from low-cost producers outside Europe.
To tackle these challenges, HARARE aims to make the metallurgical industry more sustainable by implementing a circular concept based on two strategies. The first strategy involves recovering waste materials such as flash smelter slag from primary copper production and bauxite residue from aluminum production, which are typically disposed of as waste, creating environmental issues. By using hydrogen instead of carbon as a reductant, the industry can become free of CO2-emissions and decrease its dependence on hard coal imports.
HARARE's initiative is important for creating a less carbon-dependent metallurgical industry necessary for a sustainable future. The use of hydrogen-based processes offers a promising avenue for decarbonizing the sector, reducing greenhouse gas emissions, and increasing energy efficiency, thereby contributing to sustainable development goals. Additionally, HARARE's approach can have a significant impact on the economy, as the metallurgical sector is a significant contributor to Europe's economy, with over 300,000 people employed in the EU alone. By reducing energy costs and becoming more sustainable, the sector can increase its competitiveness in the face of intense competition from low-cost producers outside Europe.
The HARARE project (Hydrogen As the Reducing Agent in the REcovery of metals and minerals from metallurgical waste) was a four-year initiative funded by the European Union’s Horizon 2020 program. Its primary objective was to eliminate waste from the metallurgical industry by recovering valuable materials through CO2-emission free processes using hydrogen as a reductant. The project focused on two major waste streams: copper slag and bauxite residue (red mud) from alumina production.
Work Performed and Main Results
Work has been structured across several work packages (WPs) to validate hydrogen-based technologies from laboratory to demonstration scales.
• Bauxite Residue Treatment: Research has focused on two primary pathways: the "Calcium (Ca) route" and the "Sodium (Na) route".
• Copper Slag Valorization: The project explored the reduction of copper slag by injecting hydrogen into liquid slag.
• Sustainability and Safety: Comprehensive Life Cycle Assessments (LCA) and socio-economic impact assessments were initiated to compare hydrogen reduction pathways against current waste management practices. Additionally, specialized work packages addressed the health and safety logistics of handling hydrogen in high-temperature metallurgical environments.
Overview of Final Period Results
As the project reaches its final stages, the focus has shifted toward integrating individual unit operations into cohesive flowsheets for industrial application. Key results include the demonstration of iron concentrate recovery and the validation of multi-stage leaching processes for rare earth element extraction. While technical feasibility has been established, economic analysis suggests that bauxite residue treatment currently requires optimized reagent recycling, lower electricity prices, or gate fees to be fully economically viable. Conversely, copper slag treatment has shown a positive cash flow potential early in the assessment.
Exploitation and Dissemination
• Exploitation: Commercial activities include the development of business plans for new products and services, such as specialized binders and recovered metallic products. Non-commercial exploitation focuses on spin-off research and contributing to new standards for hydrogen use in process metallurgy.
• Dissemination: Dissemination efforts have been robust, featuring an international seminars like the one held in May 2024 in Trondheim, Norway. This event facilitated the sharing of results with stakeholders from industry and academia, covering topics from hydrogen safety to the kinetics of iron ore reduction. The project also maintains an innovation database to manage intellectual property and ensure that findings reach the European Clean Hydrogen Alliance and other relevant industrial pillars.
Work Performed and Main Results
Work has been structured across several work packages (WPs) to validate hydrogen-based technologies from laboratory to demonstration scales.
• Bauxite Residue Treatment: Research has focused on two primary pathways: the "Calcium (Ca) route" and the "Sodium (Na) route".
• Copper Slag Valorization: The project explored the reduction of copper slag by injecting hydrogen into liquid slag.
• Sustainability and Safety: Comprehensive Life Cycle Assessments (LCA) and socio-economic impact assessments were initiated to compare hydrogen reduction pathways against current waste management practices. Additionally, specialized work packages addressed the health and safety logistics of handling hydrogen in high-temperature metallurgical environments.
Overview of Final Period Results
As the project reaches its final stages, the focus has shifted toward integrating individual unit operations into cohesive flowsheets for industrial application. Key results include the demonstration of iron concentrate recovery and the validation of multi-stage leaching processes for rare earth element extraction. While technical feasibility has been established, economic analysis suggests that bauxite residue treatment currently requires optimized reagent recycling, lower electricity prices, or gate fees to be fully economically viable. Conversely, copper slag treatment has shown a positive cash flow potential early in the assessment.
Exploitation and Dissemination
• Exploitation: Commercial activities include the development of business plans for new products and services, such as specialized binders and recovered metallic products. Non-commercial exploitation focuses on spin-off research and contributing to new standards for hydrogen use in process metallurgy.
• Dissemination: Dissemination efforts have been robust, featuring an international seminars like the one held in May 2024 in Trondheim, Norway. This event facilitated the sharing of results with stakeholders from industry and academia, covering topics from hydrogen safety to the kinetics of iron ore reduction. The project also maintains an innovation database to manage intellectual property and ensure that findings reach the European Clean Hydrogen Alliance and other relevant industrial pillars.
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.
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.