Red mud or bauxite residue contains significant quantities of industrial
metals such as Fe, Al and Ti, and rare earths such as Sc, Ce, and La. The
authors performed a laboratory-scale project work dealing with stepwise
recovery of valuable elements from two bauxite residues, namely Iranian red
mud (IRM) and Turkish red mud (TRM). In the first stage, it was tried to
recover iron which is present in large quantities in red mud. Two different
methods have been investigated for this purpose: 1) solid state reduction
followed by wet magnetic separation, 2) smelting. In the scope of this
paper, some results of pyrometallurgical part of this project are presented.
According to solid-state reduction experiments, it was found that more
excess coal was needed for IRM (35%) than TRM (15%) to maximize iron
reduction. Temperature had significant effect on the reduction process and
metallization increased from about 70% to about 95% when the temperature was
raised from 1000 to 1200?C. Metallization degree was reported to be slightly
higher for IRM (96.2%) than TRM (94.1%). The results demonstrated that a
high degree of iron metallization can be achieved regardless of the chemical
and mineralogical composition of the bauxite residue sample.