Ferroalloys DC Smelting Plant

Robust, safe, and easy to operate, our DC furnace solutions are custom-designed for each individual application. The optimized furnace and feed system layout makes it a highly cost-efficient solution.

• Continuous electrical direct current supplied by transformer and rectifier    
• Graphite electrode forms negative cathode and the bottom of the furnace the positive anode    
• Smelting energy supplied by open plasma arc    
• Raw material reduced at high temperature with carbon reductant such as anthracite or coal    
• Alloy sinks to the bottom and slag floats at the top; these are tapped intermittently through dedicated tap holes    
• Off-gas, mainly carbon monoxide, is cleaned and can be reused as combustible fuel    

Cost-efficiency is further improved with the possibility to use cheaper, lower-grade reductants such as anthracite or coal. We can provide a complete solution for a wide range of production capacity requirements, with typical furnace power ranging from 10–45 MW. Our offering includes proprietary technology, process design, and fabrication services, as well as supervision, training, and operation and maintenance services.

The flexibility of the Metso Outotec DC furnace opens up opportunities for exploiting reserves that would have been considered economically unattractive using conventional smelting technology. Typical applications include fine chromites, ilmenite, low-grade laterites, and dust generated during steel production, especially stainless steel.

One of the biggest benefits of DC smelting technology lies in recycling applications. It can be used to process and recover valuable metals from materials such as the dust resulting from the production of steel and other metals. Traditionally these materials would have ended up in landfill, but with Outotec DC smelting they can be processed without any agglomeration.

Metso Outotec DC smelting is suitable for a wide range of commodities and applications, including:

• Ilmenites (Ti) and titaniferous magnetites (Ti, V)    
• Chromites (Cr)    
• Laterites (Ni)    
• Steel-plant dusts (Ni, Co, Cr)    
• Slag cleaning (Co, Cu, Ni, V)    
• Blast furnace slag (Pb and Zn fuming and condensing)    
• Platinum group metal smelting (including Pt and Pd)    
• Dolomites and magnesites (Mg)    

Metso Outotec DC smelting can be combined, for example, with the Metso Outotec ferrochrome process to enable efficient treatment of all side streams.

Metso Outotec DC smelting can also be combined with the Outotec rotary kiln for energy-efficient ilmenite smelting, or Metso Outotec circulating fluidized bed (CFB) technology as part of the modified Metso Outotec circonickel process for laterite smelting.