Jyväskylä University of Applied Sciences and University of Jyväskylä have launched a research project on the use of soda sediment and ashes from pulp factories as a substitute of cement in concrete. Forest industry produces significant amounts of soda sediment and ash, which are classified as waste and are largley non-utilized.
It is estimated that 50,000 tons of soda sediment end up in landfills in Finland annually. The target of the Sustaining bioresiduals (Kestävä bioresiduaali) project is not only to find new ways to utilize soda sediment but also to reduce the amount of cement in concrete.
If all soda sediment now ending up in landfills could be used in concrete manufacturing, it would reduce the total use of cement by some five percent total. This would decrease the carbon footprint of concrete construction significantly. At the moment, cement manufacturing creates some five to ten percent of the human carbon dioxide emission globally.
Another target is to create new circular economy in Central Finland by developing know-how of the small and medium-sized companies of the region. Companies in concrete industries can exploit the know-how from the project in their own activities in developing new, low-carbon products and product families.
A press release from the University of Jyväskylä points out that there are some scientific releases published on the use of soda sediment as concrete substitute. Up to now, its use as a substitute has not been actually tested anywhere.