This so-called bioasphalt will be used to pave a total of 800 meters near Koeru, including five short stretches of highway and three stretches of a light traffic path.

"The goal is to reduce dependence on petroleum products," explained Mart Arusoo, head of construction at the Transport Administration's Road Management Division. "These are indeed our first real field tests, to see how this [material] performs and how well the road will hold up in real life."

The lignin used in this asphalt is produced by the Estonian company Fibenol. Reet Nõmmoja, a representative of the company, explained that lignin is a glue-like substance found in wood that strengthens and protects it, adding that it imparts similar properties to asphalt.

"Using unique technology, we add value to local waste and low-quality wood; we're putting it to smart use here," Nõmmoja said.

Oliver Kiisler, director of the Production Department at road construction company Tariston, confirmed that the use of lignin does not alter the technology used to lay asphalt. The lignin added to the road surface is, however, four times more expensive than bitumen.

"It may be more expensive, but if it gives us the opportunity to use Estonian-produced materials for roads, then perhaps it's a very good replacement," Kiisler added.

Along various sections of asphalt near Koeru, the Transport Administration will be testing out mixtures where 5, 10 or 15 percent of the bitumen it contains is replaced with lignin.

At Tallinn University of Technology (TalTech), which is collaborating on the development, work is already underway to develop asphalt with significantly higher lignin content.

"There will definitely be more pilot projects," Arusoo confirmed. "For example, we're heavily involved in a Government Office-funded innovation project in which lignin has already replaced 30-40 percent [of bitumen] in laboratory conditions. But it's still too soon to talk about that; that's a topic for the future."

--

Follow ERR News on Facebook and Twitter and never miss an update!