Zambia's copper smelters plan extended shutdowns, squeezing output and chemical supplies

Two of Zambia’s largest copper smelters and sulphuric acid producers will shut for extended maintenance later this year, two industry sources said, further squeezing copper output and supplies of the chemical used to process copper and cobalt.

The Iran war has disrupted global supplies of the critical acid and other leaching chemicals, prompting mines in neighbouring DR Congo – the world's top cobalt and second-largest copper producer – to cut usage or consider output cuts.

Copper smelters in Zambia – Africa's No.2 producer of the metal vital for clean energy technologies – generate about 2 million metric tonnes of sulphuric acid a year, mostly as a byproduct used by local mines, the mines ministry says, with excess exported to the Democratic Republic of Congo.

The Southern African country's own sulphuric acid stocks are so depleted that there is effectively no capacity to export, the Zambia head of Canada's First Quantum Minerals told Reuters separately, as miners in neighbouring DRC also struggle with tightening chemical supplies.

Zambia tightens control of sulphuric acid exports

Although copper smelters shut annually for routine maintenance spanning 30 days, Mopani and Chambishi, which are 85% owned by a Chinese company, face longer outages this year, a chemicals trading source said.

Mopani, which has not been maintained for a while, is scheduled to close for three days in June, followed by an extended shutdown of about 40 to 45 days between August and mid‑September, a mining executive told Reuters.

Chambishi is scheduled to shut down for about two months through August, the chemicals trader said, without elaborating on what prompted the planned extended outage.

Zambia tightened controls of sulphuric acid exports this month, requiring traders to secure permits. It said the move was aimed at protecting local industry.

Constrained output

Global copper supply will tighten this year after years of constrained mine output growth. Zambia produced 890,346 tonnes of the red metal ​last year, below a 1 million-tonne target.

DR Congo's copper exports, meanwhile, fell in the first quarter of this year, according to shipping data seen by Reuters.

Mopani is operating well below its 225,000‑metric‑tonne finished copper capacity after years of underinvestment left it short of copper concentrate, the mining executive said.

The majority owner, UAE's International Resources Holding, is developing and mining concurrently, forcing intermittent stoppages and further constraining output, said the mining executive.