In 2013, Fortum commissioned the world’s first industrial-scale, “bio-oil plant” integrated with a combined heat and power (CHP) plant in Joensuu (FI). The targets of the investment were to increase total efficiency and the value of the existing CHP plant, as well as to explore the possibility of new interesting business opportunities. The new plant has an annual capacity of 50.000 tonnes of bio-oil from wood-based fuels. The use of bio-oil has a significant positive environmental impact because the energy produced with it can reduce greenhouse emissions by up to 90% as compared with fossil fuels. The bio-oil plant was supplied by Valmet as a turnkey delivery. In Joensuu, bio-oil is produced mainly from wood chips using fast pyrolysis technology. Constructed in connection with a fluidised bed, the solution features a reactor where the wood is vaporised. In fast pyrolysis, wood is decomposed in an oxygen-free atmosphere at high temperatures. The resulting vapors are condensed and the end product, bio-oil, looks and smells like tar.
Bio-oil can be used as a replacement for heavy and light fuel oil at heat plants or in the production of industrial steam. Fortum’s bio-oil has been successfully used at Savon Voima’s heat plant in Iisalmi and at the company’s own heat plants in Joensuu and Espoo (FI). In 2015, Fortum exported its first batch of 160 tonnes of bio-oil for test combustion at E.ON’s Karlshamn power plant in Sweden. As one of the biggest peak-load and reserve power plants in the Nordic countries, this plant wanted to decrease its environmental load and get further assurance that biofuel can replace some of the heavy fuel oil in the future. In the successful test combustion, bio-oil was incinerated at a record output of 175 megawatts.
Currently Fortum and Valmet are further developing and optimising the process as well as testing other feedstocks, such as forest residues and sawdust. The target is to maximise fuel flexibility, while maintaining the required quality parameters, such as heating value. In the future, bio-oil may become a valuable raw material for various biochemical or traffic fuels. To promote this development, Fortum and Valmet have joined forces in the LignoCat project, which develops catalytic pyrolysis technology to produce high-value biofuels that replace fossil transportation fuels and to create new business for the consortium companies.