After almost 5 exciting years, the SisAl Pilot project has ended. These years have been filled with lots of labs and pilot-scale experiments both in pyro and hydro, intense discussions about Life Cycle Assessment and future business cases, and last but not least incredible memories from project meetings around the globe. The consortium has constantly worked on implementing innovative pilots for Silicon production, with low environmental impact, using secondary Aluminium and silicon raw materials.We have demonstrated that the SisAl process is not just possible on a small scale but also on a large scale! It has been shown that different types of silicon and alumina qualities can be produced with the process.
METLEN’s hydrometallurgical pilot teams achieved the replication of NTUA’s lab scale results, in producing more than 50 kg of ACH (AlCl3*6H2O) from the SISAL slag. The ACH is a precursor for the production of High Purity Alumina (HPA) of 4N grade. The results and data collected from this pilot campaign were used to make the final techno-economic and environmental analysis of the SISAL process with the HPA slag valorization option.
Precipitation of ACH from slag leach solution through HCl gas purging @ METLEN
MINTEK demonstrates SisAl process by producing silicon metal with a carbon-free reductant. This process focuses on the production silicon and silicon alloys from secondary silica-containing materials by using secondary aluminium sources as reductants. Mintek pilot test work demonstrated aluminothermic reduction smelting of a calcium-silicate slag through addition of solid aluminium bars.
SisAl Pilotis approaching the end of the second year and thereby also the mid-term of the project. Looking back at the time that has passed many promising results have been produced at different scales by the project partners both on the pyro- and hydrometallurgical side. The mass flow models, LCA models and business cases have been improved, which together with the experimental and modelling results have given us more confidence in the implantation and commercialisation of the SisAl pilot process. This year has also given us many positive memories from meeting partners at different locations in Europe and also at Mintek in South Africa. We hope that you will enjoy reading each partner’s summery of their achievements during this year and last but not least we would like to thank all our partners for very fruitful and successful collaboration that we hope and believe will continue during the third and fourth year of the project.
During this first year, the project successfully performed small-scale experiments in WP2 used as input in the upcoming pilot trials at Elkem. The separation of the different compounds through hydrometallurgical treatment has been optimized in WP3 and the modelling team in WP5 has created initial HSC and LCA models in which data from small-scale experiments have been used to verify the models. Data from the pilot experiments in WP2 and WP3 will be included when these will be available.
