Lignin is a polymer that is part of the cell walls of plants and that gives wood its stiffness and mechanical strength. The properties allow lignin to replace part of the fossil oil-based binder called bitumen that is found in asphalt. Stora Enso’s lignin, Lineo® by Stora Enso, comes from Nordic forests with traceable origin, and is produced at Stora Enso’s Sunila Mill in Finland. Stora Enso is the largest kraft lignin producer in the world.
“Asphalt consists of stone and bitumen, which is a product made from crude oil. Now that we have been able to find something that can replace bitumen as a binder in the asphalt mass, our negative climate impact will be reduced dramatically,“ explains Mattias Andersson, Asphalt Product Specialist at Svevia.
Håbo is the first municipality in Sweden to invest in the climate-smart asphalt over a longer distance than anyone has done before. Several test stretches with lignin have been paved in Sweden in recent years, but no one has previously paved a continuous stretch of 1.7 kilometers, which requires a more large-scale production. In total, Svevia will produce close to 1,200 tonnes of asphalt mass with lignin for the assignment in Håbo. The performance of asphalt with lignin on Svevia's test section in Gnesta has proven to be very good.
“We actively work with our Lineo offering to replace fossil-based materials with renewable ones. Asphalt is an excellent example where crude oil is replaced with a material made from trees,” concludes Heikki Lotti, Sales Manager, Lignin, at Stora Enso.