Process Flow Sheet

The NiWest Project aims to produce LME cathode nickel and a cobalt carbonate precipitate. The process flow sheet consists of open cut mining, crushing, agglomeration and ore stacking, multistage leaching, acid regeneration, iron removal/neutralisation, solvent extraction and electrowinning.

The heap leach solution circuit incorporates the iron removal and acid regeneration process. The heap leach utilises a dynamic on/off pads system whereby spent ore is removed and disposed of in a pit.

The Pregnant Liquor Solution (PLS) generated from the heap is directed to solution neutralisation where iron is removed followed by solvent extraction and electrowinning. Cobalt is recovered separately as a precipitated carbonate product. Residues generated from DSX-EW process are co-disposed in a pit with spent ore.

Sulphuric acid will be sourced from the region and transported to site via rail and road transport. The plant’s energy requirements will be provided by natural gas fired generators, with gas sourced from a gas pipeline running through the project. Calcrete for neutralisation can potentially be sourced in the vicinity of the project.

Bateman Tenova designed and built Copper SX EW plant in Chile. SX units are located in two banks in foreground. Electrowinning refinery is housed in the large building at rear. Plant is similar in conceptual layout and size (1.5mtpa) to the proposed NiWest processing facility.