Sustainable Copper Production Based on Fluid-Bed Roasting Technology

Fluid-bed technology plays a crucial role in the pyrometallurgical processing of various ores and concentrates. This paper discusses the extensive research and development by Metso Outotec over the past 50 years to broaden the applicability of fluid-bed technology in copper production. Specifically, it highlights processing routes that include partial, sulfate-producing, and dead roasting, with a particular emphasis on the advantages of the dead-roasting process. This innovative approach is characterized as a 'zero waste' process, capable of yielding valuable by-products such as copper oxides, steam, electrical power, and sulfuric acid, which can be utilized by existing solvent extraction–electrowinning plants. Additionally, fluid-bed roasting emerges as a sustainable solution for operations depleting their oxidic ore resources, ensuring the continuous supply of copper oxides. The paper positions fluid-bed roasting technology as a cost-effective alternative to traditional two-stage smelting methods, particularly for smaller capacities or lower sulfur content materials, thereby enhancing the overall sustainability of copper production.