Gold Roasting, Autoclaving or Bio-Oxidation Process Selection Based on Bench-Scale and Pilot Plant Test Work and Costs

摘要

Most refractory gold ores require a pre-oxidation step such as roasting, pressure oxidation, or bio-oxidation to enhance gold recovery with conventional cyanidation. To select the most appropriate pretreatment process and to understand process chemistry, the use of bench and pilot scale test work is required. Once in operation, these laboratory techniques can also assist in selecting the optimum operating parameters for the large-scale plant. While laboratory techniques will facilitate process understanding, in order to ensure that all objectives are met, process selection must be performed recognizing other constraints of the project. An overview of generic key criteria will be discussed. Test limitations and shortfalls will be highlighted. Ore types and project specifics must also be considered in the process selection.