South Africa’s national mineral research organisation Mintek has achieved a significant milestone in sustainable metallurgy by demonstrating production of manganese ferroalloys using carbon-free reductants.

This new cutting-edge method, called the HAIMan process, uses hydrogen and aluminium instead of traditional carbon-based materials, eliminating CO₂ emissions and generating zero waste. Simultaneously, it converts manganese-rich waste into valuable products, making the process both cleaner and more efficient.

With industries worldwide facing increasing pressure to reduce waste, cut energy use and lower carbon emissions, Mintek is putting South Africa at the forefront of green metallurgy.

Traditionally, making ferromanganese alloys required extremely high temperatures in electric furnaces, leading to large amounts of CO₂ emissions.

The HAIMan process changes this by replacing carbon-based reductants with hydrogen and aluminium; the hydrogen burns cleanly and produces only water instead of harmful gases.

HAIMan consists of two steps, the first being the pre-reduction step and the second the smelting step.

Pre-reduction uses hydrogen gas as reductant, and the smelting step uses aluminium metal as reductant.

By eliminating CO₂ emissions, HAIMan not only transforms waste materials into valuable resources but also achieves a remarkable zero waste outcome.

Further, the slag generated during the smelting phase is effectively recycled, allowing for the recovery of alumina, grey mud, and residues that can be repurposed in cement manufacturing.

“This method stands at the forefront of sustainable practices, significantly reducing environmental impact while enhancing energy efficiency. The HAIMan process promises a cleaner, greener future for alloy production, showcasing that innovation can meet industrial needs without compromising our planet,” Mintek, located on Malibongwe Drive, in Randburg, Gauteng, stated in a release to Engineering News & Mining Weekly.

“Ferromanganese alloys are critical to South Africa’s economy, as they are widely used in iron and steel production and the welding industry. Recognising the urgent need to revitalise this sector, Mintek has partnered with leading organisations from Europe and South Africa, with support from the European Union’s Horizon programme, to implement the HAIMan process. This initiative aims to introduce the most energy efficient production methods while significantly cutting CO₂ emissions,” the State-owned organisation explained.

Mintek pyrometallurgy division executive manager Dr Elias Matinde shared positive results from the latest HAIMan tests: “This testing successfully demonstrated carbon-free production of manganese ferroalloys with a manganese content exceeding 70%.

“Our environmental evaluations further confirmed negligible CO₂ emissions, highlighting the HAIMan process’s potential to significantly contribute towards decarbonising the production of manganese ferroalloys. We are extremely proud of the progress we are making in pyrometallurgy as we continue to showcase our expertise,” Matinde added.

Mintek CEO Dr Molefi Motuku emphasised that revitalising the ferromanganese industry was one of Mintek’s key strategic programmes.

“South Africa has an abundance of manganese, yet the country is not fully benefiting from its ferroalloy resources. Industry players, government, and researchers all agree that more must be done to develop local capacity, improve competitiveness and unlock greater economic value.

“Mintek is committed to revitalising the ferromanganese industry by driving innovation and commercialising cost-effective, low- carbon production technologies. The HAIMan process is a major step in this direction, helping to position South Africa as a leader in sustainable ferroalloy production while contributing to industrial growth, job creation and long-term economic sustainability,” Motuku said.