Use of Ash after Denitrification as an Additive to Concrete Based on Alcali-Activated Slag

Abstract:

This paper deals with the possibility of using fly ash after denitrification by the SNCR method a partial replacement in alkali-activated concrete based on blast furnace granulated slag. Previous research has verified the use of fly ash after denitrification in alkali-activated materials based on blast furnace granulated slag, and so far no negative effects on the properties of these mixtures have been found. The tests were performed on cement test specimens. As part of the preparation of concrete mixtures, two recipes were prepared. The first reference mixture contained only blast furnace granulated slag activated by sodium water glass with silicate modulus of 2. The second recipe was modified by replacing of 30% slag by fly ash after denitrification by SNCR method. Within the strength characteristics, the reference mixture always achieved better results. Very slow increases in strength were recorded for the mixture with 30% slag replacement by fly ash, when the compressive strength after 7 days of maturation was only 4.5 MPa.

• Periodical: Solid State Phenomena (Volume 322)
• Pages: 78-83
• DOI: https://doi.org/10.4028/www.scientific.net/SSP.322.78
• Online since: August 2021
• Authors: Lukáš Prochazka*, Jana Boháčová
• Keywords: Blast Furnace Granulated Slag, Concrete, Denitrification, Fly Ash

References

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DOI: 10.3389/fmats.2019.00009

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DOI: 10.1016/j.matpr.2020.04.594

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