A. Maldonado-Alameda, J. Mañosa, J. Formosa, J. Giro-Paloma, J.M. Chimenos
https://doi.org/10.3390/app11093840
Applied sciences, 2021, 11, 9, 1-15
Quartile Q2, Impact 2.679
Alkali-activated binders (AABs) stand out as a promising alternative to replace ordinary Portland cement (OPC) due to the possibility of using by-products and wastes in their manufacturing. This paper assessed the potential of weathered bottom ash (WBA) from waste-to-energy plants and PAVAL® (PV), a secondary aluminium recycling process by-product, as precursors of AABs. WBA and PV were mixed at weight ratios of 98/2, 95/5, and 90/10. A mixture of waterglass (WG) and NaOH at different concentrations (4 and 6 M) was used as the alkaline activator solution. The effects of increasing NaOH concentration and PV content were evaluated. Alkali-activated WBA/PV (AA-WBA/PV) binders were obtained. Selective chemical extractions and physicochemical characterization revealed the formation of C-S-H, C-A-S-H, and (N,C)-A-S-H gels. Increasing the NaOH concentration and PV content increased porosity and reduced compressive strength (25.63 to 12.07 MPa). The leaching potential of As and Sb from AA-WBA/PV exceeded the threshold for acceptance in landfills for non-hazardous waste.
Funding
The research leading this project has received funding from the Spanish Government (BIA2017–83912- C2–1-R). This work has been partially funded by a Catalonian research Grants (FI-DGR 2017 and FI-DGR 2020).
Research category: Environment and Construction
Projects associated: Desarrollo sostenible de cementos activados alcalinamente a partir de escorias de incineración de residuos municipales (BIA2017–83912- C2–1-R)
Doctoral Thesis related: Alkali-activated binders based on municipal solid waste incineration bottom ash