The construction of what is reported to be Africa’s largest direct-to-blister flash smelter, being constructed for copper/nickel/zinc miner Ivanhoe Mines at the Kamoa-Kakula copper complex, in the Democratic Republic of Congo (DRC), is 56% complete and on target for commissioning in the fourth quarter of 2024.

Progress on the Phase 3 expansion project, reported by Ivanhoe Mines in August, includes the integration of the direct-to-blister flash smelter, which will have a capacity of 500 000 t/y of greater than 99%-pure blister copper anodes.

The on-site smelter is being built adjacent to the existing Phase 1 and Phase 2 concentrator plants.

The smelter will incorporate modern technology supplied by industrial machinery company Metso Outotec and will meet global financial resource provider International Finance Corporation’s emissions standards.

Progress to date for the smelter includes all major foundations for the equipment and buildings having been completed, while most of the structural steel and equipment have been ordered and are now being manufactured. The first orders of structural steel and mechanical equipment have been delivered to site.

About 726 truckloads of steel and equipment out of an estimated total of 5 400 have been delivered.

The miner also reports that the main mechanical and electrical construction contractors have been appointed and mobilisation thereof is under way.

Mechanical assembly of the direct-to-blister flash furnace, electric slag-cleaning furnace and gas cleaning system has also started.

About 2 000 construction workers are now working at the smelter site, and this number is expected to peak at 3 000 in December.

According to the Kamoa-Kakula 2023 prefeasibility study, smelter commissioning is expected to drive a decrease in average cash costs over the first five years (from 2025) to about $1.15/lb of copper, a 21% reduction from the midpoint of the 2023 guidance of $1.45/lb of payable copper produced.

In addition to construction works at the mine, Kamoa-Kakula’s Phase 3 expansion also includes the refurbishment of turbine number 5 at the Inga II hydroelectric power station, which is situated about 1 400 km away, but through which the mine intends to procure lower-emissions electricity.

A joint venture with DRC’s State-owned power company will see turbine number 5 produce 178 MW of renewable hydropower, which – together with the upgrading of the Mwadingusha hydropower plant and its 78 MW contribution – will provide the Kamoa-Kakula copper complex and associated smelter with sustainable electricity for future expansions.

The supply of an additional 178 MW of clean hydroelectric power to the national grid of the DRC, is sufficient to meet the power requirements of the Phase 3 concentrator and the flash smelter.

Further, study work is also progressing well to upgrade the transmission capacity of the existing grid infrastructure between the Inga II hydropower facility and the Kamoa site.

New Copper

The 99%-pure blister anode copper produced from Kamoa-Kakula’s smelter is expected to be among the lowest carbon-dioxide emitters in the world per ton of copper produced.

The smelter will have a processing capacity of about 1.2-million tons a year of dry concentrate feed and is designed to run on a blend of concentrate produced from the Phase 1 and 2 Kakula, and Phase 3 and future Phase 4 Kamoa, concentrators.

Under the Kamoa-Kakula 2023 integrated development plan, the smelter is projected to accommodate about 80% of Kamoa-Kakula’s total concentrate production.

Kamoa-Kakula will also continue to toll treat concentrates under a ten-year agreement with the Lualaba Copper Smelter (LCS), located about 50 km from Kamoa-Kakula, near the town of Kolwezi.

Deliveries to LCS are expected to account for about 150 000 t/y of copper concentrate, and as a by-product, the smelter will also produce between 650 000 t/y to 800 000 t/y of high-strength sulphuric acid.

The on-site smelter will offer “transformative financial benefits” for the Kamoa-Kakula copper complex, Ivanhoe Mines reports, most notable being a material reduction in logistics costs, and to a lesser extent, reduced concentrate treatment charges and local taxes.

Logistics costs accounted for 32% of Kamoa-Kakula’s total cash costs during the second quarter of this year, and the volume of shipments is expected to halve following the Phase 3 expansion as trucks will transport 99%-pure blister copper anodes instead of concentrate with about 50% contained copper.