Stora Enso and Peab Asfalt paved an area of the Sunila pulp mill in Kotka, Finland, with asphalt in which part of the fossil-based bitumen has been replaced with renewable lignin from wood. Lignin, one of the main building blocks of a tree, is renewable and bio-based, and can be used as a responsible alternative for fossil-based binders in bitumen, for instance. Source: Timberbiz
The new asphalt mixture was used to pave part of the wood field at Stora Enso’s Sunila Mill and the road leading to the mill’s harbour area. The kraft lignin used in the asphalt has been extracted in the pulp production process at the Sunila Mill. Stora Enso is the world’s largest producer of kraft lignin; Sunila Mill has a capacity of 50,000 tonnes of kraft lignin per year.
Lignin is a natural binder in wood that can be used as a substitute for oil-based bitumen in asphalt.
The purpose of the test paving is to determine the overall impact of lignin on the properties of asphalt and its carbon footprint. Lignin can also be used as a substitute for fossil-based raw materials, for example, in batteries and adhesives.
The test will monitor the load and wear resistance of the test pavement, including its ability to withstand weather and seasonal variations, high loads and torsional forces.
“We see this as an excellent development for our mill. We are proud to bring a more environmentally friendly asphalt made from our own Lineo lignin to the Sunila Mill. This innovation is a great way to celebrate the 150-year history of Stora Enso in Finland and the forest industry in Kymenlaakso area,” said Timo Tidenberg, Sunila Mill Director.
This is Stora Enso’s first lignin paving project in Finland. Stora Enso and Peab Asfalt have already tested lignin-based asphalt on several roads in Sweden.
