GUATEMALA – Pilot-scale leaching tests of limonite ore from the Fenix laterite nickel project have been successfully completed, reports owner SKYE RESOURCES of Vancouver. The high-pressure acid leach (HPAL) process achieved nickel recovery rates of over 96% from two separate deposits, Area 215 and Area 217. However cobalt extraction was 97% from Area 215 and 95% from Area 217. Leaching temperatures, retention time in the autoclave and sulphuric acid feed were comparable for the two types of ore.
Skye believes that the success of the pilot plant test work demonstrates the technical viability of recovering nickel and cobalt from the Fenix limonite with a HPAL process. The work illustrates the potential additional value of the significant limonite resources at Fenix that are not currently included in Skye’s mineral reserve estimates.
Sufficient data were collected during the pilot campaigns to develop design criteria for a prefeasibility study, the next step in the development of a hydrometallurgical expansion.
HPAL nickel and cobalt extractions were relatively high compared with extractions achieved for many laterite deposits. Leach residue CCD thickener performance was particularly outstanding, said Skye. Pilot plant thickener underflow densities were consistently high, and static and dynamic testing of pilot plant samples suggested thickener unit areas of less than 0.1 m2/t per day solids are possible.
Visit www.SkyeResources.com for more information about the Fenix project, formerly known as Eximbal.