The utilization of waste incineration filter dust (WIFD) in sodium carbonate activated slag mortars

Abstract The presented work utilizes Waste Incineration Filter Dust (WIFD) as a green ingredient in a sodium carbonate activated ground granulated blast furnace slag (GGBFS) system. WIFD is produced with a high portlandite and calcite content in MSWI incineration plants. The reaction kinetics and reaction products of the system are analyzed through isothermal calorimetry, X-Ray diffraction (XRD), thermogravimetric analysis (TG-DTG), FT-IR, SEM/BSE/EDX, BET tests. The flowability and compressive strength of WIFD mixed samples are evaluated. The results show that the WIFD and Na2CO3 have a synergistic effect on the activation of GGBFS. The portlandite from WIFD could replace the pure Ca(OH)2 and react with Na2CO3 to improve the alkalinity. The incorporation of WIFD accelerates the Na2CO3 activated GGBFS with the main products, including C-(A)-S-H gel, hydrotalcite and hemicarbonate. Besides, the calcite from WIFD is beneficial to form the hemicarbonate and decrease the porosity of the matrix. Though the mechanical performance of samples is reduced with more WIFD, it’s still high enough for a potential application in construction with lower strength requirements. The results also confirm that GGBFS could be activated by WIFD along and the addition of sodium carbonate helps the strength development and increases reaction speed. The work shows the potential of WIFD applying as a green building material.