A new modernised hydrogen-ready anode furnace was launched to the market in December 2024 by Finnish industrial machinery manufacturer Metso to improve impurity removal and offer innovative reductant options to reduce emissions.

The Outotec Anode Furnace has been designed to reduce CO₂ emissions during copper smelting, while also offering increased flexibility in processing various secondary materials.

“Raw materials pose both great challenges and opportunities for copper smelters today. Whether it is bringing in new primary concentrates, utilising existing ones with degrading quality or integrating secondary raw materials into existing processes, the demand for flexibility in the unit processes is growing,” says Metso anode casting and anode furnace technologies senior sales manager Miikka Marjakoski.

At the same time, he says smelters are looking to identify potential reduction sources for greenhouse gas (GHG) emissions, while the evolving raw material base is not making this paramount task easier.

The upgraded anode furnace features the latest design, advances in process safety and ease of maintenance.

It also presents two methods for reducing CO₂ emissions through either direct hydrogen reduction in the hydrogen-ready (H₂-ready) variant or through a steam-gas reduction system.

“The process is fully prepared to use direct hydrogen reduction in the H₂-ready variant. However, if the customer has no opportunity to switch to hydrogen use at present, Metso can also provide the technology to significantly increase the current gaseous hydrocarbon reductant efficiency with a steam-gas reduction system,” says Marjakoski.

When combining this with oxyfuel combustion at the burners, he says, the total reduction in CO₂ emissions is demonstrably significant compared with traditional processes, which has also been proved through lifecycle assessment calculations.

The anode furnace delivery scope consists of all key equipment required for operating the furnace, while Metso’s holistic competence in smelter process optimisation and integration of automation systems ensures that the furnace will be seamlessly integrated into the processing chain in both brownfield and greenfield applications.

When combined with services and onsite support, a smooth commissioning and startup is ensured, notes Metso.

Meanwhile, Metso’s Scrap Melting Furnace variant of the anode furnace presents an opportunity to treat a substantial amount of secondary raw materials by using integrated burners for melting purposes.

The Outotec Scrap Melting Furnace yields great flexibility in treating any mixture of molten copper from upstream processes and high-grade secondary copper feed directly into the anode furnace, explains Marjakoski.

He adds that it can be used as a standalone melting furnace using solely secondary raw materials, making the product a “go-to choice for primary and secondary smelters alike”.