JOHANNESBURG (miningweekly.com) – The uncommon earths restoration undertaking which is underway in South Africa’s Limpopo province, is seen as one of many world’s most resilient uncommon earths initiatives at a time when these parts are in widespread demand in everlasting magnets to assist the world go inexperienced.
Rainbow calculates that it has a extremely financial grade of uncommon earths within the gypsum stacks at Phalaborwa, the place the 25-million-tonne useful resource offers for 16 years of restoration of 4 of the world’s most wanted uncommon earth parts (REEs).
Some 150 000 t of those uncommon earths will likely be produced at an working expenditure (opex) believed to be the bottom of any undertaking within the West and doubtless even under that of the East.
Two months in the past, even when the costs of the 2 key everlasting magnet REEs – neodymium and praseodymium – have been at $47/kg to $48/kg, Rainbow would have been worthwhile had it been in manufacturing.
Costs have since recovered to about $60/kg for the 2 parts, which in 2022 have been at $180/kg, all of the forecasts are for rising uncommon earth costs.
“We imagine this is without doubt one of the most resilient uncommon earths initiatives on the earth,” George Bennett, the CEO of the London-listed South Africa-led Rainbow Uncommon Earths, proclaimed at this week’s Mintek@90 occasion, lined by Mining Weekly. (Additionally watch the connected Creamer Media video.)
“The truth that we may obtain such a low opex makes this undertaking very resilient. In the intervening time, no uncommon earth initiatives on the earth are earning money at present uncommon earth pricing,” he mentioned.
A big-scale pilot plant, which has been constructed as a part of Rainbow’s shut collaboration with Mintek since 2022, operated on the excessive degree of 20 kg per hour of feed, making it six to 10 occasions the scale of a standard pilot plant. A reclaim trial run on the phosphate gypsum was run in February this 12 months very efficiently and the plant will likely be rerun in January/February to show up remaining stage separation.
Concerned is the primary industrial restoration of REEs from phosphogypsum, which makes Rainbow Uncommon Earths one thing of a pioneer.
The provision of phosphogypsum is the results of the mining of a hard-rock phosphate deposit, which has been carried out by Foskor for the final 60 years.
The mined materials is concentrated by way of a flotation course of right into a phosphate slurry, which over the interval has been the feed for a close-by phosphoric acid plant, the place two key elements have been added, specifically sulphuric acid and warmth to create phosphoric acid.
The uncommon earths within the phosphate slurry have been additional upgraded within the phosphoric acid sludge within the phosphoric acid plant after which that phosphoric acid manufacturing created a gypsum waste residue that was transported in a concentrated kind to the gypsum stacks.
The occasion was held to mark Mintek’s 9 a long time of pioneering contributions within the minerals and metallurgy sector by South Africa’s Council for Mineral Know-how, which derives its mandate from the Minerals Know-how Act.
At the side of Mintek, Rainbow has developed a one-of-a-kind flowsheet that allows the industrial extraction of key uncommon earths out of the phosphogypsum.
Displayed on a big display screen was an previous opencast mine that had been mined for a few years, an previous Sasol phosphoric acid plant that had not been working for ten years and two unlined environmentally hazardous gypsum stacks.
“Rainbow’s undertaking’s going to scrub this all up into a really environment-friendly state,” Bennett promised.
The ready-fenced and power-lined website has a high-voltage change yard, reflecting the appreciable benefits of being on a brownfield location.
