Synergistic effect of hydration and carbonation of ladle furnace aslag on cementitious substances

Abstract

Ladle furnace slag (LFS) can undergo hydration and carbonation reactions as cement. This article explores the effect of LFS hydration and carbonation reactions on cementitious substances at different temperatures and different LFS particle sizes, determining the effect of these varying conditions on the microstructure and formation mechanism of cementitious substances. The results show that in the early stages, C2S and C3S undergo hydration to generate C–S–H gel, which then undergoes decalcification and condensation to generate CaCO3 and Ca-deficient C–S–H gel; the hydration reaction and carbonation reaction promote and influence each other. The increase in temperature was found to hinder the formation of CaCO3 from Ca2+ and CO32−, thus reducing the efficiency of hydration carbonation. The increase in particle size was not conducive to the leaching of C2S and C3S to the surface of the reaction phase, which in turn reduced the degree of decalcification and polymerization of the C–S–H gel in the carbonation phase. It was concluded that the optimum LFS hydration and carbonation reactions were achieved at 20 °C and with a LFS particle sizes < 38 μm.

Ladle Furnace Slag: Synthesis, Properties, and Applications

“…3 gives the CO 2 binding capacity and conditions used in different studies. Yi et al [160] explored the synergetic effect of hydration and carbonation on the cementitious properties of steel. Both processes tend to promote each other, with the methods working the best for particles with smaller sizes.…”

An Insight into the Chemistry of Cement—A Review

“…Particular attention has been dedicated to the key role played by water in the hydration reactions occurring in OPC, and the different types of compounds generated during this step. In this context, the recent literature [22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39][40][41] clearly highlights the pivotal interest still present in the development of new advanced cement and cementitious materials. Even if cement is a well-consolidated material, the chemistry of cement (and the chemistry inside cement) remains very complex and not obvious.…”