Behavior of CO2 Absorption in Wet-grinding of Electronic Arc Furnace Reducing Slag by Vibration Ball Mill

Abstract

A fundamental study was carried out in order to fix CO2 on slag. The electronic arc furnace reducing slag was wet-ground by a vibration ball mill under CO2 atmosphere. The effect of grinding conditions on the behavior of CO2 absorption was investigated.The rate of the absorption of CO2 under wet grinding was larger than that under dry grinding. The total amount of CO2 absorption increased with the increase in total amount of the slag and water in case that the weight ratio of the water to the slag was kept constant. The CO2 was fixed as CaCO3 and Ca4Si2O6(CO3)(OH, F)2. Any compounds of Mg were not detected by XRD after the experiment. In the early stage of grinding, the CO2 was absorbed even if the grinding was stopped. The concentration of Ca in the water was larger than the solubility of Ca(OH)2. Hence, the absorption of CO2 was determined by the surface reaction that consisted of chemical reaction and mass transfer in liquid. In the latter stage of grinding, the CO2 was not almost absorbed immediately after the grinding was stopped. The concentration of Ca in water was small. Accordingly, the absorption of CO2 was influenced by the dissolution of slag into water.The amount of the exhausted CO2 was calculated from the electronic power which was necessary for operating this experimental apparatus. The amount of CO2 absorption was larger than that of the exhausted CO2 from a solar, an atomic, a wind and a water power plant.