LignoBoost plant handed over to Stora Enso’s Sunila mill
Stora Enso's Sunila mill employees are now running the Valmet-supplied LignoBoost lignin separation plant.
By Cindy Macdonald
The last part of the handover process, the lignin dryer, was taken over by the Stora Enso team on September 15, 2015. The LignoBoost plant is integrated with the pulp mill to separate and collect lignin from the black liquor.
Stora Enso views the lignin plant as a significant step in transforming the Sunila mill into an innovative and customer-focused biorefinery. The plant has been running since January 2015 and production has been ramped up during the year.
“Through the lignin extraction process we have replaced a great amount of natural gas with the dried lignin produced in the new LignoBoost plant, and by doing that reduced our carbon dioxide emissions. We are developing this new product and working together with our customers to start external sales,” says Sakari Eloranta, senior vice-president, operations and investment projects, Stora Enso Biomaterials.
Valmet reports that the Sunila installation is the second commercial-scale LignoBoost plant in the world. “We continue to develop this technology, as we see a great potential in utilizing lignin in various uses. Lignin powder can be used as raw material at the mill for firing or it can be converted into other materials and products. Lignin separation will at the same time improve the environmental performance of the mill,” says Anders Larsson, director, bio materials, pulp and energy business line, Valmet.
LignoBoost is Valmet’s patented method of extracting lignin from the spent cooking chemicals in the kraft pulp process, known as black liquor. By treating the black liquor with carbon-dioxide and a strong acid the lignin is precipitated. It is then washed and dried. Lignin is an organic polymer and has a heating value similar to carbon.
In addition to LignoBoost, Valmet has several bio initiatives, including products such as bio coal, solutions for second generation ethanol, pyrolysis oil, direct and indirect gasification of biomaterials.
Stora Enso Biomaterials offers a variety of pulp grades to meet the demands of paper, board and tissue producers. The Sunila mill has an annual capacity of 370,000 tons of softwood pulp. The mill employs approximately 160 people.