The key themes in the Innovation and Skills in Finland 2021−2027 program are a carbon-neutral Finland and the transition to a circular economy. With climate change, the construction industry has recently paid more attention to sustainable construction and using natural materials.
Clays in Southwestern Finland have been found challenging when used as construction materials, e.g., due to the high water content and, in some places, the high sulfur content and acid production potential (acid sulfate soil material). There is little information on how excavated Finnish clays can be utilized as a part of the built environment. Adding more information allows for the broader use of clay. In Finland, large volumes of potentially usable clay must be transferred and disposed of from construction and civil engineering projects. The utilization of these clay masses requires new ways of studying and treating the masses, and to this, the SARA project seeks to find new solutions. Local excavation clays could be used in clay construction instead of being placed, for example, in urban landfill areas. Clay masses already deposited can also be used if the properties of the clays and their suitability as raw materials for new products are known. The aim is to find new uses and thus promote the transition to a circular economy.
If the clay could be used to make products without firing, it would save energy during the production stage. In addition, reducing natural raw materials and construction waste favors the use of clay in ecological construction. The goal is to develop and obtain unfired clay tiles and bricks suitable for construction use. The strength of unfired clay products can be improved by adding recycled materials, such as textile fibers, natural fibers, or fibrous waste streams from the forest industry. Due to the large clay volumes to be excavated during construction, the clay should also be used in infrastructure projects. Surplus clay has been used, e.g., in the construction of noise barriers and to stabilize softer grounds to be built on. New larger-scale uses could be, for example, flood protection products or other prefabricated constructions. In infrastructure construction, ashes and slags from local heat and combustion plants can also be used to substitute ordinary cement.
The primary result of the project is to provide the target groups with information on recycling and utilization of domestic clay. Companies can use the results of this project to develop new green growth businesses. The project will enable better reuse of material and waste streams alongside and as substitutes for virgin natural resources.
