A bsorption and fixation of CO_2 to waste materials that contained Ca

为开发含钙废渣--电弧炉废渣、还原炉渣和氧化渣吸收固定CO2的工艺，开展了基础性研究。本研究用离心式球磨机和振动球磨机将这些材料在CO_2中湿法和干法粉碎，研究了粉碎条件对CO_2吸入量和吸收速率的影响。主要研究结果如下：1)湿法磨矿使含钙物料比干磨更能吸收CO_2。2)还原渣中CO_2的量和初始速率最大，氧化渣次之。3)振动球磨机的样品CO_2量和初始速率大于离心式球磨机。4)用振动球磨机粉碎还原渣时，CO_2的吸收率取决于实验初期广泛定义的CO_2与水溶液之间的界面反应。在实验的后期，炉渣在水中的溶解是速度控制步骤。5)湿法磨还原渣的CO_2吸入量与粉磨过程中CO_2排放量的最大差值为104 mg(CO_2)/g(渣)。该工艺可实现钢铁工业CO_2减排目标的五分之一。此外，还发现较大的振动磨和间歇湿法磨能更有效地吸收CO2

Fundamental research was carried out in order to develop the process in which CO_2 was absorbed and fixed to Ca containing waste materials, that is, waste torte, reduction and oxidation slag from electric arc furnace. In this study, those materials were wet and dry ground in CO_2 by a centrifugal ball mill and a vibration ball mil Effect of grinding conditions on the amount and the rate of CO_2 absorption was investigated. The main obtained results were summarized as follows;1) The wet grinding enabled Ca contained materials to more absorb CO_2 than the dry grinding.2) The amount and the initial rate of CO_2 of the reduction slag were the largest among them, and those of oxidation slag were second largest.3) The amount and the initial rate of CO_2 of those samples by the vibration ball mill were larger than those by the centrifugal ball mill.4) When the reduction slag was ground by the vibration ball mill, the absorption of CO_2 was determined by the widely defined interfacial reaction between CO_2 and the aqueous solution in the early stage of the experiment. In the latter stage of the experiment, the dissolution of the slag into water was rate controlling step. In the other experiments, the absorption of CO_2 was determined by the dissolution of the slag into water.5) The largest difference between the amount of CO_2 absorption on the reduction slag by wet grindings and that of emission of CO_2 in the grinding was 104mg(CO_2)/g(slag). This process will be able to attain one fifth of reduction target of CO_2 in iron and steel industry. Furthermore, it was revealed that the larger vibration mill and intermittent wet grinding were able to absorbed CO_2 more effectively