Influence of ore processing behavior on heap-leach cyanidation and agitation leaching efficiency

Abstract

The study addresses efficiency of heap-leach cyanidation as function of processing properties of ore. The grain size composition, chemistry and mineralogy represent the main ore properties. The test ore samples contain up to 76% of aluminum and silicon oxides. The ore features a few impurities and a moderate amount of sulfide sulfur (0.6%). Assaying after preliminary gravity separation of gold shows that average Au content is 1.74 g/t (site 1) and 1.43 g/t (site 2). This research aims to analyze the processing properties of ore and assess expediency of heap-leach cyanidation of this ore. The representative samples for the heap leach tests are the primary sulfide ore. The lab-scale tests of agitation cyanidation of ore samples from different sites were carried out using bottle agitator. The scope of the analysis also embraced the influence of the ore size and cyanide concentration on the leaching efficiency. Furthermore, adsorption of gold from cyanidation solutions was also tested. The cyanidation products were subjected to atomic adsorption spectroscopy (solution) and assaying (cake).