Composite Copper-Graphite Cooler for PGM Furnace Sidewall

The corrosionCorrosion of copper coolingCopper cooling elements in the sidewall of platinumPlatinum group metal (PGM) furnacesFurnace is unique in its severity and nature. ‘Chloride-accelerated sulphidation’ has been identified as the most likely corrosion mechanism and is prominent in the zone directly adjacent to the slag-concentrate interface. Tenova Pyromet developed a new composite copper-graphiteGraphite cooler for implementation in one of Sibanye-Stillwater’s circular PGM furnaces at their Marikana smelter complex. The cooler designDesign is unique as, in addition to the hot face, the sides, bottom, and top of the cooler are completely covered with graphite, preventing contact between the copper cooler and the sulphur- and chlorine-bearing species thought responsible for the corrosionCorrosion. The designDesign of the cooler and test work performed to evaluate its effectiveness are discussed. The coolers have been in operation since August 2022. The implementation and performance of the coolers to date are discussed.