SCALE-Up demonstrates a commercialization-ready flowsheet for producing Sc-products from Bauxite Residue. Leaching and separation takes place as integrated process within the MYTILINEOS’s alumina plant, extracting from 850,000t/a of Bauxite Residue, 67t/y of crude Sc concentrate. The concetrate is refined at SCAVANGER into 22t/y of pure Sc2O3, which is then returned to MYTILINEOS’ Al smelter for production of 733t/y of Al-Sc2% master alloy.
Following the recent successful conclusion of the H2020 SCALE-730105 Research & Innovation Action, SCALE-Up pursues the commercialization of the Sc production value chain from Bauxite Residue (BR). The “SCALE-technology” for leaching and extracting Sc from BR was validated at TRL 6 at the MYTILINEOS industrial pilot plant (Greece). 9 t of BR were processed producing 10 m3 of leach solution, which was processed in an ion-exchange (I-X) pilot to produce the first Sc concentrate at 22 wt. % Sc. To fuel this demonstration and to extract reliable upscaling data, MYTILINEOS will process 30-40 t of BR (~1.5 year of operations) in its pilot plant. The overall process flowsheet will be optimized by recycling waste streams and investigating alternative reagents/resins for key operational points reaching TRL 9. Using the produced concentrate, SCALE-Up will demonstrate at TRL 8 the refinement steps for Sc concentrate to produce 99.99% Sc2O3 at pilot scale. Finally, SCALE-Up will design the upscaling plant and establish the business model for a processing unit of 850,000 t of BR/a to produce 14.6 t of Sc/y .
The envisioned upscaled plant, at MYTILINEOS with a processing capacity of 2000 t of BR/d, will deliver 62 t of Scandium concentrate/a. The concentrate will be processed at ScaVanger company (MEAB+KTH), which will produce up to 22 t/y of Sc2O3 and/or up to 32 t/y ScF3. These compounds will be either sold for SOFC production or used in MYTILINEOS for AlSc master alloy production at each primary Aluminium Smelter.Thus, the recovered 14.6 t of Sc from the 850,000 t of BR will be converted into 733 t of AlSc2 master alloy/y, currently priced at 100-150 €/kg. AlSc2% alloys are forecasted to dominate heat exchangers and lightweight mobility (aerospace) applications in the coming decade. Current EU Sc production is non-existing , and Al-Sc production is limited to 1-2 t/y.