SANTIAGO, March 17 (Reuters) - Codelco, the world's biggest copper producer, said on Tuesday it was still working to get a key production unit at its newest mine running at capacity, following a delayed and problematic start-up process.
The roaster, used to reduce levels of arsenic in the ore at the Ministro Hales mine to make copper ready for use in traditional smelters, is still not fully operational.
"It's still in the start-up phase. When it's running at capacity we will inform (the market)," the Chilean state-owned company told Reuters.
Codelco admitted for the first time last July that Ministro Hales was behind schedule because of problems with the roaster. In November it said it was undergoing repair work and would restart around early December.
Finland's Outotec made the roaster and will, under contractual obligations, cover any costs relating to fixing the equipment, Codelco said in October.
Ministro Hales, which was in its ramp-up phase in 2014 and produced 109,000 tonnes of copper from January to September, is emblematic in many ways both of Codelco's hopes and its challenges.
It has been key to boosting copper output but has been dogged with problems at the roaster, which sources said forced it to delay sales in China last year.
Codelco, facing high energy prices and falling ore grades, is plowing billions of dollars into revamping old mines and launching new projects in a bid to secure its top spot. (Reporting by Fabian Cambero; Writing by Anthony Esposito; Editing by Dan Grebler)