Odilon Kasongo Ilunga
MSc in Engineering from the University of the Witwatersrand
Processing Manager at Weatherly Mining Namibia & part-time lecturer at University of Namibia
The interaction between molten blister copper and 316L stainless steel
The use of mild steel lances in blister copper conversion was identified as a cause of production inefficiency because of an excessive maintenance requirement due to corrosion at the Tsumeb smelter in Namibia. An alternative substitute made of 316L stainless steel was investigated in order to determine its performance at the smelters' working conditions. The 316L stainless steel crucibles contaminated the copper. Under industrial conditions, and over longer periods of time, the effects were worse, and any 316L lances deteriorated fast. Since the liquid miscibility gap occurred very near 100% Cu, it would be better to avoid any ferrous material, and instead use refractory linings, which are used for the larger vessels, which would also reduce diffusion.
Work plan:
- Melting blister copper using crucibles and lance made of 316L stainless steel in neutral or oxidizing conditions at different temperatures.
- Analyzing different microstructures resulting from the interaction, by means of Energy Dispersive X-ray Spectrography (EDX), Scanning Electron Microscope (SEM), Backscattered electrons (BSE), Secondary electron image (SEI).