The main aim of SCALE is the efficient exploitation of EU high concentration scandium containing resources including bauxite residues (100-150 ppm) resulting from alumina production and acid wastes (50-100 ppm) from TiO2 pigment production to develop a stable and secure EU scandium supply chain to serve the needs of EU aerospace and high tech industry. This will be achieved through the development of a number of innovative extraction, separation, refining and alloying technologies that will be validated in an appropriate laboratory and bench scale environment to prove their technical and economic feasibility.
Among them, Scandium (Sc) is one of the highest valued elements in the periodic table and an element which is often grouped in REE as it shares many characteristics of Yttrium. Scandium technological applications are unique, as it is a key component in producing Solid Oxide Fuel Cells (Scandia-Stabilized-Zirconia solid electrolyte layer), high strength Aluminum alloys used in aerospace, 3D printing applications (SCALMALLOY®) and also finds important applications in electronics and ceramics.
Its average crustal abundance is 15-25 ppm and the possible, independent, scandium mineral deposits are generally insignificant in size and grade, with certain notable exceptions in some clay resources where scandium concentration may be in the the range of 100 – 150 ppm. For this reason most of today’s scandium production tends to come as a byproduct of the leaching activity associated with production of other metals, minerals, or rare earths, specifically U, Th, Al, W, Sn, Ta, P and REE’s.
A potentially significant scandium resource is the bauxite residue (red mud) tailings from the Bayer process, employed in bauxite processing into alumina. Bauxite residue typically contains 50-100 ppm Sc, but certain tailings can show concentrations of up to 150 ppm, rendering them as highly important resources for scandium production, provided that there is a technically feasible and economically viable technology for the recovery of scandium from the bauxite residue. Titanium dioxide production residues (acid waste) also contain similar Sc concentrations.
The principal Sc-producing countries today are China, Russia, Ukraine, and Kazakhstan. Currently there is no Scandium production in Europe. There are important EU based industries including Airbus, II-VI, KBM Affilips and others, that need to use scandium in a good number of applications that will give them significant competitive advantage and are not deploying their Sc applications due to the lack of a stable and secure Sc supply.
Recent studies show that the forecast for scandium consumption will grow from today’s 14 t/y to about 300 t/y with Solid Oxide Fuel Cells (SOFC) and Aerospace industry sharing the biggest part in this consumption. A major industrial interest is shown in the use of scandium in the construction of a new generation of lighter aircrafts and this fact stimulates the need to urgently establish an indigenous EU scandium production to preserve the competitive advantage of our strong and healthy aerospace industry.
Moreover, it has to be emphasised that on contrary to the dropping prices of REE the last years, scandium prices remain considerably high ranging between 1500 – 4500 USD/kg according to scandium oxide purity. Taking into consideration the scarcity of scandium resources and the increased scandium demand in the near future it is not expected that this trend will be reversed additionally stressing the need for a stable, secure and of reasonable cost EU scandium source.
In this frame the main aim of SCALE is the efficient exploitation of EU high concentration scandium containing resources including bauxite residues (100-150 ppm) resulting from alumina production and acid wastes (50-100 ppm) from TiO2 pigment production to develop a stable and secure EU scandium supply chain to serve the needs of EU aerospace and high tech industry. This will be achieved through the development of a number of innovative extraction, separation, refining and alloying technologies that will be validated in an appropriate laboratory and bench scale environment to prove their technical and economic feasibility.
The industrially driven SCALE consortium is led by 2 European alumina refineries (AoG, AOS) and one TiO2 pigment producer (TRONOX) who are joined by the key Sc producers and end-users in Europe like II-VI (Sc2O3 producer / optical applications), LCM (REE metal producer), KBM (Al-Sc alloy producer) and AIRBUS (Al-Sc end user/ SCALMALLOY® 3D-Printing technology). Furthermore SCALE features 8 academic & research institutes and 4 engineering companies with track records in their fields; SCALE builds on the success of previous and on-going European research projects like ENEXAL, EURARE, REECover, REE4EU and REMAGHIC.