JOHANNESBURG (miningweekly.com) – A bankable feasibility study (BFS) on the Steenkampskraal rare earths mine, in the Western Cape, will be concluded in the next 6 to 12 months, says Steenkampskraal Holdings chairperson Trevor Blench.
The mine is one of the highest-grade rare earth and thorium mines in the world, with average grades of 14.4% rare earths and 2.14% thorium.
“We also have to finalise the process and detailed engineering design of the processing plant that we will build. When the BFS has been completed, we will know what the actual capital budget requirement will be, which we currently estimate at around R500-million,” Blench told Mining Weekly Online.
After finalising the BFS, Steenkampskraal Holdings will work to secure the necessary financing to build the processing plant and other required infrastructure. Construction is estimated to take around 12 months to complete.
Blench noted that the mine’s estimated total cost of production, which includes mining, beneficiation and chemical processing, is about $3/kg of the mixed rare earth oxides.
“Owing to the high-grade resource, we will have low operating costs. To produce one ton of rare earths we need to mine about 10 tons or less ore, whereas most other rare earth projects have to process between 50 t and 100 t of ore to produce 1 t of rare earths because of the lower grades of such resources,” he said.
MINE DESIGN
The mine design was developed to make optimum use of the existing underground infrastructure.
“Steenkampskraal is a former producing mine, with Anglo American having mined it for ten years in the 1950s. There is a shaft, already developed stopes and much additional infrastructure in place. Our mine plan involves making the most of the existing infrastructure, which will save us 80% of mine development costs,” Blench pointed out.
He added that the company would only have to put in around 20% of the required capital for the underground mining operations to start, saving a lot of time and money.
He explained that the mine design was based on conventional stoping techniques, tramming the ore to the bottom of the incline shaft and hoisting the ore up the incline shaft.
With a target production rate of 2 700 t/y of mixed rare earth oxides, about 30 000 t/y of ore will be mined and processed, after allowing for ore dilution during the mining process.
At this rate of production, mine life will be about 25 years.
APPLICATIONS
There are seventeen different rare earth elements, some rarer and others more abundant.
“These elements have many different uses and applications. Their present relevance and importance are related to their uses in technologies that reduce carbon emissions and combat global warming and climate change,” Blench said.
Rare earths are used to make magnets that are used in the electric motors that provide power for appliances, robots and electric vehicles (EVs).
“The most important application is for EVs. [EV demand is] growing rapidly globally and they have electric motors that use rare earths magnets, which is increasing the demand for rare earths,” Blench noted.
He pointed out that renewable energy is another key rare earth application, adding that the magnets that are used in wind turbines are also made from rare earths.
He further pointed out that neodymium magnets, for example, are used in industries such as electrical motor manufacture, medical science and renewable energy which rely on high-strength neodymium magnets.
“Life as we know it would come to a grinding halt without rare earths,” he said.