SAO PAULO (Reuters) - Brazilian miner Vale will announce on Friday a 70 billion real ($12.2 billion) investment to expand its iron ore and copper mining operations at the Carajas complex in northern Brazil, the presidential palace said on Wednesday.

The investments will be carried out through 2030, the presidential palace said, adding the announcement will be made at an event with Brazilian President Luiz Inacio Lula da Silva and members of his cabinet.

Vale did not immediately respond to a request for comment.

Brazil's presidential palace said Vale will present its "New Carajas" project, but it did not give further details.

($1 = 5.7587 reais)