Use of fly ash and phosphogypsum for the synthesis of belite-sulfoaluminate clinkerDolenec, Sabina (Avtor) Žibret, Lea (Avtor) Fidanchevska, Emilija (Avtor) Jovanov, V. (Avtor) Angjusheva, Biljana (Avtor) Ducman, Vilma (Avtor) clinkermicrostructurefly ashgypsumcalcium sulphoaluminateFly ash and phosphogypsum were used as Naturally Occurring Radioactive Materials (NORM) by-products for the synthesis of belite-sulfoaluminate clinkers. The influence of raw mixture composition and firing temperature was investigated. Clinkers and cements were examined by X-ray powder diffraction and scanning electron microscopy with energy dispersive X-ray spectroscopy. The compressive strength of the cements was determined after 28 days. Clinker phases identified included ye’elimite, ß-phase of belite, ternesite and gehlenite, while the main hydration product of the cement pastes was ettringite. The results showed that belite-sulfoaluminate cements can be fabricated with a compressive strength of 45.9 N/mm2 by firing the raw mixture (70 wt.% marl, 10 wt.% bauxite and 20 wt.% phosphogypsum) at a temperature of 1320°C/1h.Instituto Técnico de la Construcción y del Cemento20192023-10-27 08:18:30Neznano17192sl© 2019 CSIC.