CO₂ SEQUESTRATION OF CEMENT PASTE FINE POWDER AND RECYCLED FINE POWDER BY WET AND DRY CARBONATION AND EVALUATION METHOD OF FIXED AMOUNT OF CO₂

Abstract

In this study, wet and dry carbonation treatment of cement paste fine powder and recycled fine powder made from concrete was carried out, and calcium carbonate and CO₂ sequestration quantity were examined. In the wet treatment, only calcite was formed in the calcium carbonate, while in the dry treatment, vaterite and a small amount of aragonite were also formed. It was shown that vaterite aragonite and calcite could be separated and evaluated by dynamic TG, and that the calcium carbonate content could be measured accurately. It was also found that the calcium content of cement in recycled fine powder was higher when hard sandstone was used as coarse aggregate than limestone, and that the fixation potential of CO₂ was higher.