A study of mineral recovery from waste ashes at an incineration facility using the mineral carbonation method

Mineral carbonation is a well-known method for recovering minerals. Recently, the process has been combined with carbon dioxide sequestration. However, mineral carbonation generally requires large amounts of energy and mineral resources to generate carbonates. In this study, the possibility of using waste ash and an intermediate solution to recover minerals is investigated, because waste ashes contain large amounts of calcium ions. Our approach is to prepare calcium carbonate by reacting calcium containing material with carbon dioxide. For this purpose, we used a solution containing 5 wt% amine and 15 vol% CO2 and ashes collected from an incineration facility. The experimental approach consisted of an extraction step and a carbonate formation step. The CO2 precipitate and waste ashes were analyzed by XRF, XRD, and SEM. Most of the CO2 emitted was precipitated, and the carbonate formed exhibited a cubic structure. Based on the results obtained, we conclude that valuable minerals can be recovered from waste materials.