Biomass fly ash (BFA) is an inorganic solid waste produced in biomass-fired power plants. Due to the adopted coal phase-out strategy, the amount of BFA produced worldwide is increasing. Currently, most of the generated BFA is being disposed of in landfills, so more sustainable management practices are being investigated, such as their recycling in construction materials.
In this work, the valorization of two sorts of BFA as an aggregate substitute in a screed mortar formulation was evaluated. The BFAs were characterized (XRF, XRD, SEM, and particle size distribution). The influence of the incorporation amount of BFAs on the workability, mass loss upon curing, bulk density, water sorptivity (by capillary and immersion), and flexural and compressive strength properties of the screed mortar was evaluated.
The results obtained from this preliminary assessment reveal that it is possible to substitute up to 25 wt.% of sand with the two sorts of BFA understudy in the screed mortar formulation, preserving the required properties. This result enables a decrease in primary raw materials consumption, while reducing the amount of BFA disposed of in landfills, a practice with a high economic and environmental impact.
Author Contributions
Conceptualization, M.P.S. and J.A.L.; methodology, M.N.C., M.P.S. and J.A.L.; validation, M.N.C., I.V., L.A.C.T., M.P.S. and J.A.L.; investigation, M.N.C., I.V. and M.P.S.; resources, M.P.S. and J.A.L.; data curation, M.N.C. and I.V.; writing—original draft preparation, M.N.C.; writing—review and editing, M.N.C., I.V., L.A.C.T., M.P.S. and J.A.L.; supervision, M.P.S.; project administration, L.A.C.T., M.P.S. and J.A.L.; funding acquisition, L.A.C.T., M.P.S. and J.A.L. All authors have read and agreed to the published version of the manuscript.
Funding
This work was supported by Portugal 2020 through the European Regional Development Fund (in the frame of Operational Competitiveness and Internationalization Program) in the scope of the project INPACTUS, POCI/01/0247/FEDER/21874 and in the scope of the project CICECO—Aveiro Institute of Materials, UIDB/50011/2020, UIDP/50011/2020 and LA/P/0006/2020 financed by national funds through the FCT/MEC (PIDDAC). It is acknowledge the financial support to CESAM by the Portuguese Foundation for Science and Technology (FCT)/Ministry of Science, Technology and Higher Education (MCTES) UIDP/50017/2020+UIDB/50017/2020+LA/P/0094/2020, through national funds.
Institutional Review Board Statement
Not applicable.
Informed Consent Statement
Not applicable.
Data Availability Statement
Not applicable.
Conflicts of Interest
The authors declare no conflict of interest.
| Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations. |
© 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).