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The 2003 redoubling in power to 68MW on the Polokwane Smelter furnace represented a significant intensification in platinum group metal (PGM) smelting. Combined with onerous 'green' PGM concentrate smelting requirements, this yielded conditions unusually corrosive to copper coolers and refractories. This presented unexpected operational and design challenges to reliable crucible operation and maintenance. Combined with specific operational control intervention, development of protective coatings has led to the life of water-cooled copper components improving from 9 to 40 months. The furnace matte endwall was extended in 2010 to address accelerated wear of refractories and the potential risk for contact of copper components by superheated matte. An 18 month planned endwall rebuild cycle has been demonstrated (versus catastrophic failure within 9 months). Finally, benefits including lower energy consumption, improved metal recoveries and higher productivity resulting from operational and in-house design developments will be described, that justify "Celebrating the Mega-scale" in PGM smelting.

The Polokwane smelter is the only platinum-producing smelter in the area. Wet concentrate is received from various concentrators along the Eastern Bushveld Complex with 60% from the UG2 and 40% from the Merensky reef, varying in grade from 35 g/t Pt to 110 g/t Pt, from which Pt-rich Cu-Ni matte is produced. A brief description is given of the process operation, which includes concentrate receiving and flash drying, the furnace, furnace refractory and cooling system, matte handling and crushing, and water management., The Polokwane smelter is the only platinum-producing smelter in the area. Wet concentrate is received from various concentrators along the Eastern Bushveld Complex with 60% from the UG2 and 40% from the Merensky reef, varying in grade from 35 g/t Pt to 110 g/t Pt, from which Pt-rich Cu-Ni matte is produced. A brief description is given of the process operation, which includes concentrate receiving and flash drying, the furnace, furnace refractory and cooling system, matte handling and crushing, and water management.

The 30 MVA slag cleaning furnace was designed for the recovery of platinum group metals in a matte for further processing from Ausmelt converter slag and has been in operation since March 2003. Issues relating to the design and operation of the furnace included a wide variety of feed materials and resulting bath conditions. Furnace feed includes combinations of granulated converter slag, hot fed Peirce-Smith converter slag, concentrate and reverts. Coke is added as reductant. In the case of Ausmelt converter slag an almost pure fayalitic slag with a very low viscosity is obtained. The widely varying slag conditions required a robust sidewall design adjacent to the slag bath. The sidewall is equipped with a high-intensity Cu cooling system and the coolers are capable of removing peak sidewall heat fluxes above 500 kW/m2. The design and installation of the tap holes, furnace shell, furnace roof and copper slag spouts are described., The 30 MVA slag cleaning furnace was designed for the recovery of platinum group metals in a matte for further processing from Ausmelt converter slag and has been in operation since March 2003. Issues relating to the design and operation of the furnace included a wide variety of feed materials and resulting bath conditions. Furnace feed includes combinations of granulated converter slag, hot fed Peirce-Smith converter slag, concentrate and reverts. Coke is added as reductant. In the case of Ausmelt converter slag an almost pure fayalitic slag with a very low viscosity is obtained. The widely varying slag conditions required a robust sidewall design adjacent to the slag bath. The sidewall is equipped with a high-intensity Cu cooling system and the coolers are capable of removing peak sidewall heat fluxes above 500 kW/m2. The design and installation of the tap holes, furnace shell, furnace roof and copper slag spouts are described.