SKF announced a strategic investment, together with Stephen Industries and Chalmers Ventures, in startup Anferra AB to tackle one of the industrial sector's most persistent waste challenges – hazardous steel grinding sludge.
Grinding sludge is a finely powdered mixture of metal particles, abrasives, and contaminated grinding emulsion generated during metal grinding operations. It is commonly classified as hazardous waste with most non-recycled volumes handled through incineration or landfill. Globally, around 12 million tonnes are produced each year, creating both environmental risks and significant costs for industry. Additionally, variability in sludge composition makes standardized recycling difficult.
Anferra's innovative process converts steel grinding sludge into ferric chloride which is a common chemical agent used for wastewater and water treatment. Another by-product is hydrogen gas which can be further used as an energy carrier, contributing to green energy solutions. This enables a potential net climate benefit of negative 470 kg CO₂-equivalents per tonne of sludge (equal to driving an electric car for 7500 km) compared to conventional disposal.
The process achieves up to 90% iron recovery with significantly lower energy demand, effectively transforming a costly waste problem into a valuable resource stream. Most importantly, the technology has the potential to shift grinding sludge from being treated as hazardous waste towards becoming a secondary raw material, aligning with the EU's efforts to harmonise waste regulations and build a stronger market for secondary raw materials.
"Grinding sludge is one of the toughest recycling challenges in the steel and bearing industry. Anferra's approach represents a smarter way forward and positions us well to drive circularity and decarbonization. This investment, which is the first initiative coming out of SKF Ventures – SKF's initiative to accelerate new innovations, enables us to influence solution development, positioning SKF as a first mover in circular recycling innovations and creating new value from waste streams," says Mikael Krook, Director, SKF Ventures.
"We are very happy to deepen our collaboration with SKF through this investment. SKF has been an important partner since the early stages of Anferra's development and with their support and close collaboration, we can accelerate our journey toward industrial implementation around the world. Our ambition is to significantly reduce the landfilling of grinding sludge while increasing circularity and resource efficiency on a global scale," says Ebba Adolfsson, CEO and Co-founder, Anferra.
This investment brings together complementary expertise across the three investors. Stephen Industries brings its expertise in scaling high-impact deeptech and greentech ventures. SKF contributes with industrial application knowledge, waste stream volume, and decades of experience in sustainability leadership. Chalmers Ventures provides venture building capabilities and close connection to the research ecosystem, enabling further development and commercialization.
SKF applies various circularity principles across its operations, including, remanufacturing bearings and circular oil use via RecondOil. Other initiatives such as exploring recycled steel solutions with ultra-low emissions and investigating hydrometallurgical methods are underway tot minimize resource loss and accelerate the transition to a net-zero, more circular industrial ecosystem.
