- Recovers valuable metals such as gold, zinc, copper, and cobalt
- Generates steam or power without CO₂ emissions
- Produces sulfuric acid
Gold concentrate roasting, most commonly known as dead roasting, uses Metso's circulating fluidized bed technology. When using a dead roasting process for concentrates, the sulfides are completely transformed into oxides. The gas temperature in this type of plant is typically between 600 and 700°C. The hot gas generated in the process is used for heat recovery and is suitable for high-pressure steam production in a waste heat boiler. Even low-sulfur and organic contents are removed efficiently, leading to increased gold recovery in the downstream leaching process.