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Solid waste derived clinker design methodology was established based on thermodynamic simulation and experiment validation via the recycling of incinerated sewage sludge ash (ISSA) and recycled concrete fine (RCF). Compared with 1000 °C and 1100 °C, 1200 °C was the optimum temperature for C 2 S-rich clinker synthesis due to the highest simulated belite content after sintering. A utilization rate of 95 % was achieved, accomplishing the maximization of solid waste recycling. Due to the CaCO 3 phase formation by the reaction of high-content belite (46.8 %) with CO 2 , carbonated 1200ARS eco-cement showed higher compressive strength than OPC and other eco-cements. The lowest porosity (18.1 %) with dense microstructure was also obtained by carbonated 1200ARS. Benefiting from the high CO 2 reactivity of belite, 1200ARS displayed the optimum CO 2 sequestration capacity with a higher carbonation degree (30.1 %) than other batches, providing a promising direction for future development of the low-carbon cement industry to achieve environmental sustainability. • A pioneering kind of solid waste derived clinker design methodology was established. • A utilization rate of 95 % was achieved, accomplishing the maximization of solid waste recycling. • Higher mechanical properties than OPC were displayed by eco-cements after carbonation curing. • The prepared eco-cements possessed excellent CO 2 storage capacity. [ABSTRACT FROM AUTHOR]

• A high-performance belite rich eco-cement was synthesized from solid wastes. • The utilization of solid wastes in the raw meal was up to 85.5 wt%. • Strong carbonation reactivity and latent hydraulic behavior promised high strength. • This technology contributed to CO 2 emission reduction and solid waste management. In this study, a high-performance eco-cement with excellent CO 2 sequestration capacity was synthesized using municipal solid waste incineration bottom ash and recycled concrete fine. The influence of clinkering temperature on the clinkers was assessed by mechanical properties, mineralogy, and microstructure. Optimal sintering at 1100 °C for 1 hour yielded eco-cement rich in β-C 2 S (44.9%), demonstrating remarkable carbonation reactivity (CO 2 uptake of 12.5%) and compressive strength (1-day strength of 113.7 MPa). The presence of carbonation products, including cubic-shaped calcite and low Ca/Si C-S-H, resulted in a densified microstructure contributing to exceptional strength. Furthermore, the eco-cement exhibited latent hydraulic behavior and recorded a 28-day strength of 136.9 MPa. Varying clinkering temperatures to 1000 °C and 1200 °C promoted the formation of γ-C 2 S and rankinite, respectively, which generated silica gel during carbonation curing and weakened the overall performance. Leaching assessments confirmed the eco-cement's reasonable merit as an alternative, high-performance, sustainable binder. [Display omitted] [ABSTRACT FROM AUTHOR]

Low-carbon emission mortar samples were prepared using reactivated cementitious materials (RCMs) produced by calcinating hydrated cement paste with adjusted Ca/Si ratios. Carbonation curing was employed to enhance the cementing capacity of the RCMs and to sequestrate CO 2. The compressive strength, phase assemblage, microstructure, and environmental impacts of the mortars were analyzed. According to the results, the mortar sample produced with the RCM with a 10% addition of silica fume during calcination attained the highest compressive strength (35.3 MPa) after water curing, while higher silica contents were unfavorable because the low-lime calcium silicates that formed have limited water reactivity. Carbonation curing significantly promoted reactions of the RCMs and, thus, the compressive strength of the mortars compared to water curing. The amorphous and metastable calcium carbonates contributed more to the densification of the microstructure than the calcite. From the life cycle assessment, the RCM mortars had a significantly lower impact on global warming potential compared to Portland cement mortars. [Display omitted] [ABSTRACT FROM AUTHOR]