Bayer + Pedersen the Perfect Match for the Future of Alumina Production, with Benefits

Within the EU-funded ENSUREAL project (GA No. 767533), significant efforts have been undertaken to recover and improve expertise from the past (Norwegian Pedersen process from the 1920s) and reach more sustainable alumina production.
The current work uses the data from ENSUREAL’s upscaling study and demonstrates a possible way to use bauxite residues from the Bayer process as feed material for the Pedersen process. Generated and available data allowed for a case evaluation considering the foreseen process equipment. An initial approximate assessment of the economic feasibility was conducted.
Treatment of bauxite residue via the electrical route of the Pedersen process produces a significant amount of pig iron. This approach fittingly meets the increasing need to electrify and decarbonize the steel industry. Combining these two processes presents the alumina industry with a promising opportunity for diversification or joint-venture activities for making better use of the raw materials.
Considering a merging of the Bayer and Pedersen processes, the typical alumina extraction rate from the bauxite increases from approximately 80% to more than 95%. Valuable pig iron is generated, covering process oncosts and generating additional revenue. The utilization of the by-product gray mud is under evaluation, and initial positive market feedback has been received. In addition to decreasing its environmental footprint, shifting alumina production to a zero-waste process reduces the financial efforts for disposal and remedial activities.
According to Charles Darwin, “It is the long history of humankind (and animal kind, too) that those who learned to collaborate and improvise most effectively have prevailed,” a perspective that could be applicable to the alumina industry as well.