PROJECT DESCRIPTION
BACKGROUND
Energy-intensive activities including steel and aluminium production use refractory, or heat-resistant, products as protective linings in furnaces. Refractory products are produced from industrial minerals including magnesite, graphite, dolomite and bauxite. For producing melted aluminium, bauxite-based refractory castables – or bauxite moulded into bricks or other shapes – are essential.
The European Union is heavily dependent on imports of refractory industrial minerals, including bauxite. The EU imports around half a million tonnes of refractory-grade bauxite each year, mainly from China. EU importers are therefore at the mercy of (restrictive) Chinese export policies.
Bauxite could be substituted by a secondary raw material that arises in the recycling of salt slag – the residue of salt used in aluminium refining. The European aluminium industry produces one million tonnes per year of salt slag from the secondary melting of aluminium scraps. Salt slag contains salts, aluminium oxide, aluminium metal and impurities and is classified in the EU as hazardous waste. It can be treated and separated into metals and non-metal residues, from which a substitute for bauxite could be derived.
OBJECTIVES
The LIFE BAUXAL-II project will set up a pilot plant and use an innovative process to transform the non-metallic concentrate which is a by-product of the recycling of aluminium salt slag into a refractory material – known as BAUXAL. This will be a suitable substitute for refractory-grade bauxites and its production will therefore reduce the EU’s reliance on imports of bauxite.
The project will demonstrate resource efficiency and contribute to the implementation of circular economy policy by replacing natural minerals with a secondary material derived from a recycling process.
RESULTS
Expected results:
- Recycle 1 000 tonnes of salt slag (hazardous waste code 100308 in the European Waste Catalogue);
- Produce at least 200 tonnes per year of the secondary refractory mineral BAUXAL from the recycled salt slag;
- Render unnecessary the extraction of 250 tonnes of bauxite and thus avoid the associated negative environmental impacts;
- Creation of a defined target market and business plan for BAUXAL;
- In the longer run, 100% of the salt slag managed by Befesa (600 000 tonnes per year) will be reprocessed using the BAUXAL process, reducing EU imports of refractory-grade bauxite by 43%.
