Pyrite roasting, most commonly known as dead roasting process and is mainly used in our zinc and pyrite roasters. 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 800 and 900°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. For gold roasting applications, even low-sulfur and organic contents are removed efficiently, leading to increased gold recovery in the downstream leaching process.
- Direct dry feeding of the concentrate (moisture content 6–12%) to the roaster
- Suitable for roasting sulfidic concentrates with a wide range of chemical and physical compositions
- High-capacity plants with a throughput of up to 1,500 metric tons per day
- High combustion velocity results in low residual sulfur in the calcine
- Maximized heat recovery in the fluidized bed in conjunction with an off-gas waste-heat boiler
- Chlorine and fluorine removed from concentrate during roasting