RE: Very informative article on PGM’s8 Jun 2022 14:30
"Tharisa’s new fine chrome processing is through their new Vulcan plant in comparison...." ...which is almost a year late and cost north of $100 million ... However, JLP has an ULTRA-fine Chrome facility ....From the WHI report in December:
Following years of research, Jubilee has refined its processing approach and now has developed a viable circuit to recover a fine chrome concentrate and a PGM-rich concentrate from the tailings associated with chromite mining. This opens up a range of waste dumps on the Bushveld for retreatment as well as allowing Jubilee to slot in a fine
recovery plant to treat tailings arising from standard chromite processing. For many years, the PGM potential in the chromite layers in the Bushveld has been recognised – indeed, the UG2 layer (see Figure 17) is one of the world’s largest resources of platinum. However, the grade of PGM in the main chromitite beds is too low to be able to process economically just for the PGMs. What the Jubilee process does is remove even more of the chromite from the waste material treated, thereby increasing the grade of the PGM and enabling a standard flotation process to recover a PGM concentrate, which can be smelted.
The chromitites are remarkably consistent (with some natural variation) but, in principle, the grade of PGM is roughly 1g/t 4E in the chromite beds, which is increased on the first standard removal of chromite to ~3g/t 4E in tailings. This “tail” from the standard chrome plants can be treated by Jubilee’s fine chrome recovery process (treating chrome <70µm) to produce a ~6g/t 4E stream for flotation and also remove a saleable fraction of chromite at the same time. Jubilee’s ultra-fine chromite plant (relocated from Dikolong) will also recover a portion of very fine-grained chrome.
The Jubilee chrome plant and ultra-fine chrome plant treats material grading ~3.2g/t PGM and 22% Cr2O3, which is classified through a cyclone with the -38µm fraction going straight to the flotation circuit rougher via a polishing mill. The +38µm fraction goes back to the spirals for fine chrome recovery (C-plant), producing a chromite concentrate grading ~40% Cr2O3 with the tails from this going to the PGM flotation circuit rougher. After scavenging and cleaner circuits, the final concentrate grading ~100g/t PGM (4E) and <2.3% Cr2O3 is sent to a PGM smelter.