Anglo American poured the first ferronickel at its $1.9-billion Barro Alto nickel project in Brazil in late March 2011. The project was approved in December 2006 and is scheduled to reach full production in the second half of 2012. Production will average 36,000 mt/y of nickel in ferronickel over a 36-year mine life, including 41,000 mt/y over the first five years of full production.
The Barro Alto project is located in Goiás state, Brazil, 170 km northwest of Brasilia and approximately 150 km from Anglo American’s existing Codemin nickel operation. Conventional smelter-refinery technology currently in use at Anglo American nickel operations is also used to process the Barro Alto saprolite ore. The processing line includes two 185-m rotary kilns and two 6-in.-line rectangular 83-MW electric furnaces.
The Barro Alto geology is complex, with three main ore types occurring in six discrete areas along strike. The laterite/saprolite ores are highly weathered and have a high moisture content. Project development was based on resources of 116.2 million mt, at an average grade of 1.54% nickel, of which 62.4 million mt at an average grade of 1.66% nickel will be mined by conventional open-pit methods and treated over a 26-year period. The plant processing rate is 2.4 million mt/y of dry ore treated.
Some Barro Alto ore has been mined throughout the project’s construction period and trucked to the Codemin plant, both to extend the life of the Codemin operation and to prove the processing technology on Barro Alto ore.