Effect of Alkali Metal Compounds on Limestone Calcination in Desulfurization Process: Molecular Dynamics Simulations

Abstract

In this study, the change in the desulfurization characteristics of limestone induced by adding some alkali metal compounds and chlorides to limestone was investigated by thermobalance experiments. In addition, molecular dynamics (MD) simulations were performed to elucidate the effect of alkali-metal chloride additions on the CaO calcination for the desulfurization process. The experimental results obtained show that the addition of NaCI into the limestone is the most effective in improving the desulfurization efficiency. The X-ray diffraction analyses of the calcined seashell, limestone and NaCl-doped limestone found that the calcined seashell, as well as the calcined NaCl-doped limestone, have a similar structure as the CaO crystal. These two materials also show a high desulfurization efficiency. The MD simulations show that NaCI doping into the CaO contributes to the crystallization of CaO, while KCI and LiCI dopings have a small contribution. Therefore, the NaCI doping has a predominant effect on the CaO crystallization leading to a high desulfurization efficiency.