Lignin from Nordic biorefineries could strengthen Sweden’s supply of critical metals

Researchers at Luleå University of Technology will investigate how lignin derived from forest biomass can be used to reduce the mining industry’s dependence on imported chemicals. The new NORDGUARD project could contribute to a more secure Swedish supply of critical metals while also reducing the environmental impact of the mining industry.

Copper, nickel, zinc and cobalt are essential to many parts of society and are also important for Sweden’s defence capabilities. But securing access to these metals is not only a question of what is available in the bedrock. Extracting them also requires various chemicals in mineral processing. If these chemicals have to be imported, production can become vulnerable to disruptions in international supply chains.

In the NORDGUARD project, researchers will investigate whether lignin, a component of wood, can be used to develop bio-based alternatives to some of the flotation reagents currently used by the mining industry.

“Critical metals are essential for both our defence capability and a functioning society. With NORDGUARD, we are taking our research on bio-based flotation reagents into an area where it can contribute directly to Sweden’s preparedness and strengthen our ability to secure our own supply of critical metals,” says Ulrika Rova, Professor of Biochemical Process Engineering at Luleå University of Technology and project leader for NORDGUARD.

Local raw materials could reduce vulnerability

Flotation is an important part of mineral processing and is used to separate valuable minerals from the rest of the mined rock. Various flotation reagents are added to make this process work.

The researchers will investigate how lignin nanoparticles can replace some of the reagents used today, with the aim of maintaining or improving the recovery of copper, nickel, zinc and cobalt. The goal is to create a bio-based alternative that can be produced regionally and reduce dependence on imported process chemicals.

“This could reduce dependence on imported chemicals and make Swedish metal production less vulnerable to external disruptions. Since lignin is a renewable raw material, there is also potential to reduce the environmental impact of mineral processing,” says Ulrika Rova.

From research to industry

NORDGUARD brings together expertise from research, the mining industry and the bioeconomy. Luleå University of Technology will develop the lignin nanoparticles and investigate how they perform in the flotation process. Chempolis Oy will contribute lignin and expertise in industrial lignin production, while Boliden Mineral AB will provide ore, process expertise and industrial validation. ONar Sweden AB will contribute expertise in scaling up and commercialising lignin-based reagents.

“The aim is not only to demonstrate that the technology works in the laboratory. We will also verify that the bio-based reagents can be used in practice and determine what is needed to eventually implement the concept on an industrial scale,” says Ulrika Rova.

In the longer term, the research could help enable more of the inputs needed for Swedish metal production to be produced in Sweden and neighbouring regions. This could both strengthen security of supply and contribute to a more sustainable mining industry.