Project Details
Projekt
C-Cure: Net-Zero Concrete with Carbonatable Binders, Rapid Reactivity Testing, Internal CO2-Curing, and Upscaling Computations
Subject Area
Construction Material Sciences, Chemistry, Building Physics
Term
since 2024
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 542229402
C-Cure addresses the SPP´s objectives - achieving net-zero concrete using alternative binders and new carbonation strategies. In Work Package 1 (WP1), a concept for carbonation binders is formulated, focusing on alternative binders, made from raw materials like limestone, clay, and sand, or wastes to create low-calcium, carbonatable self-pulverizing binders (CxS). For this, thermal processing parameters and raw materials impurity effects, including Mg, K, S, and Al, are assessed. Developing a rapid method to test carbonaion reactivity is another goal of WP1. WP2 investigates relationships between raw material composition, phase composition after the thermal processing, and the carbonation-hardening process. An innovative approach leverages CO2-amine solutions and sodium bicarbonate from carbon capture processes as internal sources of CO2 for carbonation hardening. Microstructural characterization is key to understanding phase reactivity. Elucidating the thermodynamic potential and kinetic rates of primary reaction mechanisms and resulting microstructural development is crucial for enhancing material properties. WP3 involves mortar testing, evaluating strength, slump, porosity, and more for selected binders subjected to internal and external CO2 curing. The leaching behavior of amine solutions is also a focus. In Work Package 4 (WP4), an upscaling computational approach is developed to simulate carbonatable binder curing. It considers CO2 loading, mineralogy, fillers, and polydispersity. At the pore scale, the model predicts phase assemblage, microstructure, reaction kinetics, and diffusivity dependent on moisture. The model is then homogenized to predict carbonation kinetics at the paste and mortar levels, factoring in moisture-dependent diffusion, based on mix design and mortar (model concrete elements) geometry. C-Cure combines novel experimental and computational techniques to analyze carbonatable binder kinetics. This includes innovative internal/external CO2 curing and multi-scale computations, which have not been previously considered. The insights gained will facilitate upscaling to concrete, an essential step in advancing "Net-Zero Concrete" technology. This advancement aims to address current limitations, including a lack of knowledge in three key areas: i) binder processing parameters, ii) CO2 diffusion limitations during concrete curing, and iii) binder reactivity and performance at concrete scales.
DFG Programme
Priority Programmes
Subproject of
SPP 2436:
Net-Zero Concrete
