Perth-based Lotus Resources (ASX: LOT) has moved a step closer to a production restart at the mothballed Kayelekera uranium project in Malawi with the commencement of ore sorting testwork on a 500 kilogram sample from the project site.
The testwork is being conducted at a Perth-based facility owned by magnetic and sensor separation specialist Steinert Group and has been considered an important element in improving the project’s economics.
Ore sorting technology was not available when Kayelekera was previously in production and positive results could deliver a reduction in operating costs, an increase in annual production and an extension of mine life.
Steinert will work on a “proof of concept” exercise to confirm that Kayelekera ore is suited to sorting and identify sensor technologies which produce the best results.
Once “proof of concept” has been validated, further samples featuring a range of ore types and uranium grades including lower grade stockpile material, will be sent for testing.
Lotus managing director Keith Bowes said initial results had been “highly encouraging” with visual differences easily seen between the product and reject stream.
“When Kayelekera was last in production, ore sorting was in its infancy [but] since then, the technology has advanced significantly, with far greater scope and a wider range of applications through improved detectors and faster data processing,” he said.
“While our trial work has only recently commenced, we have been very encouraged by preliminary results which show this ore is clearly amenable to the technology.”
Lotus’ testwork is employing optical and laser detection systems, as well as ‘dual energy’ XRT (x-ray transmission) whereby the radiation penetrates stones to detect differences in atomic densities and determine the normalised density of each rock.
In the case of uranium minerals, which have very high densities, ore sorting provides a clear distinction when compared with lower density waste material (or calcite).
Successful test results could materially improve the Kayelekera project by upgrading lower grade material currently stockpiled on surface and increasing uranium grades to produce a more economic feedstock.
They could also potentially extend the operation by upgrading lower grade stockpiled material (less than 400 parts per million uranium oxide) which was previously marginal at the end of the current mine life.
Further operational savings could be realised through ore sorting by rejecting high acid-consuming gangue minerals which contain minimal uranium and enabling lower acid.
The Kayelekera project hosts a current resource of 37.5 million pounds uranium oxide and produced approximately 11Mlb of uranium between 2009 and 2014.
In October, Lotus released a restart scoping study which showed Kayelekera could be among the world’s first uranium projects to rapidly and effectively recommence production to meet an impending supply shortfall.
The company’s restart timeline aligns with industry predictions of a market under-supply of approximately 30Mlbs uranium oxide by 2024.
Mr Bowes said Kayelekera’s existing infrastructure and mineral resources would allow for low restart capital costs and significant long-term production.