Further development of a chemistry proxy for geometallurgical modelling at the Mogalakwena mine

Abstract

The Mogalakwena platinum mine is Anglo American Platinum's flagship opencast operation and has been the focus of numerous optimization studies. The initial outcomes of a geometallurgical programme were reported on in 2013. This paper further describes the development of a geochemical proxy to identify different ore types at the operation and link these with various metallurgical parameters, with the aim of optimizing the value chain. At Mogalakwena, all blast-hole samples are submitted for chemical analysis by XRF prior to blasting, thus allowing the ore to be stockpiled and treated according to grade. This paper demonstrates that it would be possible to use the chemical data to stockpile and process ores according to ore type (rock type and grade), since preliminary results indicate that the metallurgical characteristics (e.g. hardness, flotation characteristics, rheology, etc.) are linked to rock composition, which defines rock types. This investigation formed part of the geometallurgical programme at Mogalakwena. The final objective of the programme focuses on risk mitigation with improved production forecasts and full implementation of the principles of geometallurgy, resulting in the optimization of metallurgical treatment and adding value to the bottom line.