Get to know our nickel operations in New Caledonia

About Vale

1/30/2015

Get to know our nickel operations in New Caledonia

New Caledonia  

The basic metals produced by Vale, such as nickel, copper and cobalt, reach us by different routes of processing, which depend on a series of factors which include the type of mineral, its location and infrastructure.

As far as nickel-copper sulphide minerals which Vale extracts in Sudbury, Voisey’s Bay and Thompson, in Canada, are concerned, the first step is to extract the greatest possible quantity of those components of the mineral extracted which do not contain valuable metals – such as rocks and some types of sulphide. At this stage of extraction, the valuable metals are concentrated into a considerably reduced tonnage of material – a concentration of metal.

As regards the nickel laterite ore which Vale extracts in Sorowako, Indonesia, in Onça Puma, Brazil, and in Goro, New Caledonia, it is not possible to produce a concentrate of metal, apart from the fact that these operations deal with the complete feeding of the mineral, with the intention of recovering the valuable metals.

The New Caledonian Operation

In New Caledonia, the operation has three autoclaves which are able to operate simultaneously for the estimated production to be attained. After the dissolution, the aqueous solution of nickel-cobalt passes through a treatment in various stages, in order to remove from these two metals the various impurities which are also to be found in the same solution. Limestone and lime are used, as well as special organic materials and solvents, in order to concentrate the nickel into a smaller volume as a pure solution of nickel chloride, and the cobalt is concentrated, separately, in a solution of cobalt chloride.

Next, the nickel is recovered from the concentrated solution of chloride, by means of decomposing the nickel chloride at high temperatures (around 800°C) inside a special reactor, transforming itself into a product of granulated nickel oxide. This product of nickel oxide is then transported to Vale’s refinery in Dalian, China, to be converted into a product of metallic nickel for the stainless steel market. The cobalt is recovered from the cobalt chloride solution as a product of cobalt carbonate, which is sold on the cobalt market.


Get to know our nickel operations in New Caledonia