OMC provided process engineering support to SNC-Minerconsult in the Jacare Project Prefeasibility Study for Anglo American Brazil.
The Jacare flowsheet, employing a High Pressure Acid Leach (HPAL) process was designed to treat surficial ferruginous ore. The leach was followed by an atmospheric neutralisation step employing pyrometallurgical dusts or saprolite ore. The discharge from the saprolite neutralisation circuit reported to the CCD circuit. The solution reported to a neutralisation circuit employing limestone for impurity removal and Mixed Sulfide Precipitation (MSP). The intermediate MSP was then leached and refined to produce nickel cathode in divided cells. The process also produced a cobalt carbonate by-product.
The leach residue was conditioned with limestone prior to disposal in a tailings facility. The water balance assured by a novel integrated evaporation step employing heat from the carbothermic smelting process used to treat other ore streams.
The Jacare Prefeasibility study was delivered to Anglo American Brazil on schedule at the end of October 2012.