New building concepts, with the help of new building materials, can make a significant contribution to introducing a carbon economy in construction, which should become as CO₂-negative as possible, as construction provides the greatest leverage in the industrial sector.
DACCUSS is investigating the storage of natural carbon in sustainably bound form based on new material systems made of carbon fibres (C-fibres) and hard rock for the development of a new structure for self-supporting house wall elements with innovative insulation made of biochar.
The technical storage of CO₂ in solid materials such as carbon fibres from biogenic sources (algae oil) was the subject of BMBF funding with the “Green Carbon Project” at the TU Munich. The green C-fibre was processed into carbon fibre stone (CFS®) in combination with hard rock and resin.
In DACCUS, the efficiency with which CO₂ for algae production can be filtered directly from the air is demonstrated. Using passive CO₂ filters (Mechanical Trees®) as an example, the entire value chain from CO₂ from the ambient air to prefabricated elements for the construction industry will be covered.
The wall is developed, built and tested from CFS®. The CO₂ sequestration potential is contained in all components of this house wall: the C-fibre, the stone and the insulation layer.
The green C-fibre has the same characteristic values as the PAN-based fibres derived from fossil sources and permanently stores 3.5kg of CO₂ equivalents per kg of C-fibre, if it is not burnt after use, as is currently the case.
The weathering of the rock used additionally contributes to CO₂ sequestration. The cut slabs of the CFS wall lead to CO₂ removal when the surfaces weather, and the rock dust produced during cutting can be used as mineral fertiliser in agriculture, for example. The resulting enhanced weathering in the soil additionally returns large quantities of CO₂ to the geological cycle.
The expected overall CO₂ balance of the wall is negative.
Partners in the project are DITF (German Institutes for Textile and Fibre Research), Labor für Stahl- und Leichtmetallbau GmbH, TechnoCarbonTechnologies, University of Hamburg and AHP GmbH & CoKG, which will subject the entire process chain to an LCA and a techno-economic analysis (TEA), as well as TU Munich/WSSB, GvU GmbH and Carbon Collect Ltd (Ireland) as associated partners.