Abstract
This project aims to transform calcium-rich slags and ashes, which are currently landfilled, into carbon-negative, high-performance binders. In part 1, the work will focus on lignite fly ash (LFA). Building upon preliminary work from a BMBF project (CO2TREAT), the carbonation procedure will be optimised for LFA, and the reactions (hydration and carbonation) as well as the resulting microstructure of the carbonated LFA will be investigated using various techniques (e.g., X-ray diffraction, Electron Backscatter Diffraction, and solid-state NMR). The aim is to unlock the potential as a supplementary cementitious material. The initiative encompasses several key work packages, more precisely a material access sampling campaign, in which we will receive fresh LFA, recover deposited LFA, and then transform the fresh and deposited LFA into SCMs for cementitious binders. We will compile the available information on deposits, conduct targeted sampling at selected locations, and conduct comprehensive characterisation and carbonation studies of LFA. Supporting these studies, a sustainability assessment based on Life Cycle Assessment (LCA) and Life Cycle Costing (LCC) will evaluate and guide the development of sustainable binders. The project findings will contribute to a broader framework for sustainable construction materials. Ultimately, this research seeks to support the transformation of former lignite mining regions and pave the way for the utilisation of other deposited industrial materials.
