Fluidised-bed incineration bottom ash as the sole precursor of alkali-activated binders: A comparison with bottom ash from grate incinerators. (18th January 2023)

• Record Type: Journal Article
• Authors: Maldonado-Alameda, A.; Mañosa, J.; Miro-Escola, J.; Quintero-Payan, A.C.; Chimenos, J.M.
• Is Part Of: Construction & building materials. Volume 364(2023)
• Publication Date: 2023-01-18
• Subjects: Alkali-activated binders -- Fluidised-bed incineration -- Moving grate incineration -- Municipal solid waste management systems -- Waste-to-energy; Building materials -- Periodicals; 624.18
• DOI: 10.1016/j.conbuildmat.2022.130001
• Languages: English
• ISSNs: 0950-0618

Abstract

Highlights: Alkali-activated binders using IBA from fluidised bed as sole precursor was assessed. The results were compared with those obtained with moving grate bottom ash. Fluidised bed bottom ashes have a higher SiO2 content but lower availability. Binders have lower compressive strength than those from moving grate bottom ash. Except for As and Sb, leached metals are below limits set for non-hazardous waste. Abstract: The novel formulation of alkali-activated binders (AABs) using incineration bottom ash (IBA) from fluidised bed (FB) combustion technology as a sole precursor was assessed. In addition, IBA-FB was compared with IBA from moving grate (IBA-MG) combustion technology. The AABs formulated with IBA-FB (AAB-FB) and IBA-MG (AAB-MG) were also evaluated from a physicochemical, mechanical, and environmental perspective. The results revealed that specific surface area in IBA-FB hinders the retention of kneading water of fresh pastes, affecting the workability, consistency, porosity, and mechanical strength of AAB-FB. Moreover, the low calcium content of IBA-FB requires that the formulated AABs must be cured at higher curing temperatures to ensure the formation of (N, C)ASH gels, while the high calcium content of IBA-MG promotes the formation of CSH gels at room temperature. The compressive strength results demonstrated that AAB-MG (≈ 11 MPa) and AAB-FB (≈ 8 MPa) could be used for non-structural purposes.