PRISMA—a hydrometallurgical process simulator: application in gold extraction from refractory pyrites

Abstract

PRISMA is a software package for process design and simulation of hydrometallurgical processes. PRISMA features are summarised as follows: (a) a user-friendly interface for flowsheet construction and data introduction; (b) flexibility in construction and modifying the flowsheet; (c) rigorous mathematical modelling of specific hydrometallurgical unit operations. PRISMA has been implemented in object-oriented language and runs on Apple Macintosh computers. Flowsheeting calculations are carried out using the standard sequential modular mode of computation. A salient feature of its integrated nature is that it supports the incrmental development of a process design by interleaving modifications of the flowsheet structure with the simulations corresponding to them. Gold production from refractory arsenical pyrite concentrates is simulated as an application case. The main unit operations involved are: aqueous pressure oxidation, counter-current washing of the oxidised solids, neutralisation of the acid wash solution, cyanidation of the solid residues and Au recovery by CIP. Detailed simulation results concerning (a) Au liberation profiles and particle size distribution changes through the autoclave compartments; (b) the influence of oxidised solids recycling on the energy balance of autoclave operation; and (c) the effect of CIP stages and initial carbon loading on the overall Au recovery are presented. Graphs. 23 ref.