Title:
Industrially produced mechanochemically activated clay - the first of its kind
Author(s):
T. Neumann, M. Fylak, A. Hamm, O. Maier, H. Möller
Publication:
Symposium Paper
Volume:
370
Issue:
Appears on pages(s):
147-154
Keywords:
mechanochemical activation, clay, sustainable cement, agitator bead mill, strength activity index (SAI), LC3 cement, Allmeca
DOI:
10.14359/51751756
Date:
5/1/2026
Abstract:
The mitigation of CO₂ emissions in cement production increasingly relies on alternative cementitious materials (SCMs), given the declining availability of traditional sources such as blast furnace slag and fly ash. This study examines the mechanochemical activation of clays as a low-carbon alternative to thermal calcination. Mechanochemical activation - implemented through high-energy dry grinding in an industrial agitated bead mill - induces pronounced structural modifications in clay minerals and enhances their pozzolanic reactivity. Experimental results indicate a lower demand for superplasticizers and accelerated early strength development in cementitious systems incorporating mechanochemically activated clays. The first industrial-scale application at the SCHWENK plant in Allmendingen (Allmeca) demonstrates the scalability of this process, which utilizes locally sourced clays and ensures consistent activation performance. Furthermore, the integration of activated clays with limestone powder, aligned with the LC3 concept, significantly improves both workability and concrete strength. This approach provides a sustainable pathway for cement production that leverages regional resources while reducing environmental impact.
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