Ivanhoe eyes higher copper output from tailings reprocessing

Ivanhoe Mines (TSX: IVN; US-OTC: IVPAF) says reprocessing tailings at its Kamoa-Kakula copper complex in the Democratic Republic of Congo has potential to increase its production of the red metal.

In a news release Thursday, the Vancouver-based miner published the results of preliminary metallurgical work conducted by Canada’s Expert Process Solutions, which has worked with Kamoa-Kakula since project inception, on improving the copper recovery rate by reprocessing the tailings stream from the two concentrators.

Since 2022, Ivanhoe’s process engineering team, together with a number of internationally recognized external metallurgy specialists, has been investigating ways to economically recover additional copper units from the tailings stream of the Phase 1 and 2 concentrators at Kamoa-Kakula.

Grinding and reprocessing the stream from the Phase 1 and 2 concentrators represents one of the 13 workstreams identified so far. The other 12 workstreams continue to be explored, including the recently announced collaboration with I-Pulse Inc.

Initial results indicate that with a feed grade of less than 1% copper, approximately 65% of the contained copper can be recovered from the stream. The results generated a saleable concentrate with a grade of approximately 40% copper that could be processed on-site at the 500,000-tonne-per-day direct-to-blister flash copper smelter that is currently under construction, Ivanhoe said. For comparison, the copper concentrate grade from the Phase 1 and 2 concentrators is currently about 50%.

Based on these results, the company appointed DRA Global, a South Africa-based company that has also been working with Kamoa-Kakula since project inception, to design the construction of a stand-alone processing plant to treat the entire tailings stream from the Phase 1 and 2 concentrators. 

According to Ivanhoe, DRA determined that the preliminary, high-level capital expenditure and operating costs associated with the construction and operation of the tailings recovery plant and the economics are significantly positive.

Year to date, the copper recoveries from the Phase 1 and 2 concentrators have improved, averaging 87.1% during H1 2023, and periodically achieving as high as 90%. However, any further sustained improvement in copper recoveries presents a significant opportunity to generate additional revenue at Kamoa-Kakula, the company said.

According to Ivanhoe’s founder and executive co-chairman Robert Friedland, the company is targeting total copper recoveries in the mid-90s from this breakthrough as well as from the other concurrent workstreams.

“Despite the Phase 1 and 2 concentrators exceeding the nameplate recovery rate, the grade of copper in Kamoa-Kakula’s tailings is still much higher than that of most major copper mines globally. This is a direct consequence of Kamoa-Kakula being the highest-grade major copper mine globally,” Friedland commented. “However, we are leaving a significant amount of copper behind… copper that this planet so desperately needs right now for our energy transition.”

“If we can recover this copper, the production profile following the Phase 3 expansion could be in excess of 700,000 tonnes per annum. Not only would this provide additional revenue and cash flow, but also it would reduce even further our tailings footprint,” he added.

Shares of Ivanhoe Mines traded at $13.61 on Friday, valuing the company at $16.5 billion.