SANTIAGO, July 23 (Reuters) - World number one copper producer Codelco confirmed on Wednesday that a key piece of roasting equipment at its Ministro Hales mine was operating at 90 percent capacity, following a start-up delay that a source had said was the cause of canceled copper sales to China.
Earlier on Wednesday, a union chief told Reuters that the roaster was operating at 90 percent and should be at 100 percent by August or September.
Some auxiliary equipment for the roaster was being modified in order to ensure continuity in its operation, Codelco said in an emailed statement to Reuters.
The Chilean state miner had asked some buyers of refined copper in China to cancel shipments due to continued problems at Ministro Hales, sources told Reuters earlier this month. The roaster built to process high arsenic ores was not working as expected, one source said. (Reporting by Fabian Cambero; Editing by Chris Reese)