The production of a pig iron and calcium aluminate slags for alumina recovery from bauxite ore.

Bauxite ore is the main raw material used to produce alumina, through the dominant
industrial method called the Bayer Process. This method causes the generation of Bauxite Residue (BR)
or red mud that creates environmental challenges. An alternative process with no BR production called
the Pedersen Process was running in Norway for almost 50 years. This process is a combined pyro and
hydro-metallurgical process in which the bauxite ore first is treated with lime and coke through a
smelting reduction process. This yields a calcium aluminate slag with pig iron as a by-product. The slag
is further hydrometallurgically treated to produce alumina. For recovering the alumina, the generated
phases must be leachable, that is containing 12CaO.7Al2O3, 3CaO.Al2O3 or CaO.Al2O3. The pig iron
byproduct can be further used in the ferrous industry and foundries. In this work, the smelting reduction
of a Greek bauxite ore is studied by using coke and biocarbon. Moreover, the characteristics of the
produced slag and pig iron are studied. The smelting reduction of bauxite shows that iron can be
separated from the slag, in addition to a suitable slag formation for further alumina extraction.