BiocharHackathon - From Raw Materials to Solutions

Located in northern Central Finland, the City of Äänekoski is one of Finland’s leading bioeconomy and industrial locations. The city actively promotes sustainable growth, the circular economy and new investments.

The City of Äänekoski is developing the Koukkuniemi business area to provide companies with a unique environment for utilising side streams, piloting new solutions and developing higher-value products and business activities.

The aim of the business area is to attract new companies, investments and jobs and to strengthen Äänekoski’s position as a circular economy frontrunner. 

L&T is one of the leading circular economy companies in the Nordic countries. It develops solutions for efficient material use, recycling and resource-smart business.

As a circular economy frontrunner, L&T continuously seeks new opportunities to transform waste and side streams into higher-value products and commercially viable business. The company sees significant potential in biochar and activated carbon value chains, including new products, markets and innovative partnerships. 

Valuable Products from Carbon Flows (HATTU), is a joint research and development project by VTT Technical Research Centre of Finland and Jamk University of Applied Sciences. The project promotes the development of a business ecosystem and new business opportunities around biochar and activated carbon in Central Finland.

The project investigates the suitability of different raw materials for biochar and activated carbon production, production processes, the quality of carbon products and the use of surplus process heat in regional heat production.

HATTU generates information on value chain development needs, commercial viability and investment bottlenecks. It also supports collaboration between companies and the further development of new solutions. The project is co-funded by European Union.

According to a biochar study commissioned by the City of Äänekoski, the region has sufficient wood-based raw materials to support industrial-scale biochar production.

The survey identified approximately:

• 29,000 tonnes of sawmill by-products
• 12,000 tonnes of class A and B recycled wood
• 33,000 tonnes of sawdust
• 59,000 tonnes of naturally dried, delimbed roundwood per year.

In addition, considerable quantities of other forest-based energy materials are available in the region.

The survey does not cover the region’s full potential because material volume data were not available from every operator. Most of the identified raw materials are already used, for example in energy production. Any new use must therefore also be commercially competitive. 

Lassila & Tikanoja’s potential raw materials include discarded pallets and other recycled wood, wood fractions separated from construction waste and other biomass streams whose potential use in biochar and activated carbon production is to be further explored.

Pallets, for example, consist mainly of untreated wood, including pine, spruce and various hardwood species. This makes the resulting material stream an interesting raw material for developing new products, business models and circular economy solutions.

Across Finland, approximately 200,000 tonnes of class A and B wood waste are generated by the construction industry each year. The annual quantities of separately collected clean recycled wood are in the tens of thousands of tonnes. In the future, other waste streams and sludges containing biomass could also serve as raw materials for biochar production. 

In addition to biochar, the pyrolysis process produces liquids, gases and heat energy. Typically, approximately one-third of the input is converted into biochar, although the proportion depends on the raw material, its moisture content and the pyrolysis process itself.

In pyrolysis, biomass is heated under controlled, nearly oxygen-free conditions at approximately 400–700°C. The raw material first dries and then begins to decompose into biochar and gaseous compounds. Depending on the process, approximately 20–40% of the dry raw material mass remains as biochar.

The process produces both non-condensable gases, such as carbon monoxide, carbon dioxide and hydrocarbons, and various liquid fractions. The gases can be used to provide energy for the process, and some can be cooled and condensed into pyrolysis oil. Heat generated by the process can be used, for example, to dry raw materials or in other regional heating solutions.

Condensation at different temperatures can be used to separate a more water-rich wood vinegar fraction containing organic acids and phenolic compounds from a heavier, tar-like hydrocarbon fraction containing aromatic and aliphatic compounds, phenols and acids.

By-product hydrocarbons can be used partly to produce process heat and heat for other applications. Their potential use as chemical feedstocks may also offer an interesting opportunity.