Fabian Imanasa Azof
The metallography characterization, chemical reactions, and leaching mechanism of calcium aluminate-slags for alumina production are investigated. The slags are produced from the smelting reduction of bauxite ore. This project employs pyro-hydrometallurgical technique, as known as Pedersen process that yields pure alumina and saleable by-product, i.e. pig iron and grey mud. It is worth to note, this process do not yield high alkaline and low utilized by-product; red mud.
The red mud has been a problem since the renowned Bayer process is practiced by over 95 % of world’s commercial production of alumina to date. Iron oxide constitutes the major compound (~ 60 wt.%) of red mud slurry, which is insoluble during digestion of bauxite in Bayer process. On dry basis, the production amount of red mud is as same as alumina, which was 120 million tons per year in 2015. Consequently, the storage size and secure location are very well concerned. Therefore, this project is believed will benefit region that has huge reserves of bauxite ore with high-iron content, i.e. central Europe.
Supervisor: Jafar Safarian (NTNU)