Intelligent control of sustainable clinker processes from recycled material

Abstract

Efforts to improve the resource efficiency and climate performance of concrete increasingly promote the use of recycled demolition materials. While coarse recycled aggregates (> 2 mm) are already used in concrete production, recycled sands and fines (< 2 mm) remain less established because of their variable quality and possible effects on concrete performance. At the same time, these fine fractions offer relevant potential for sustainable applications, including CO ₂ sequestration by accelerated carbonation and use as a calcium oxide source for recycled cement production. Within the DFG Priority Programme “Net‐Zero‐Concrete”, this study investigates the variability of fine recycled demolition materials collected over six months from industrial recycling streams. Particle size distribution, water absorption, bulk density and BET surface area were determined and evaluated with regard to their relevance for low‐temperature clinker synthesis and future process control. The results provide a basis for assessing material variability and for developing models that support consistently high product quality in CO ₂ ‐minimized recycled cement production.