Study on Carbonation of BOF Slag by Simulated Flue Gas

• Main Authors: Shi-Hau Cheng, 程士豪
• Other Authors: Pai-Haung Shih
• Format: Others
• Language: zh-TW
• Published: 2008
• Online Access: http://ndltd.ncl.edu.tw/handle/91017206920993941857

碩士 === 輔英科技大學 === 環境工程與科學系碩士班 === 97 === Basic Oxygen Furnace Slag is a residual product of steel-making process. Most Basic Oxygen Furnace Slag consist primarily of calcium and iron oxides, but cause its possession of large amount free limes, which is swelling and alkaline problem. In this study, CO2 was acidified by calcium of BOF slag which resulted in stable calcium carbonate and achieved stabilize.Calculated the weight loss between 650℃ and 900℃ using TGA analysis, we then obtained the calcium carbonate conversion rate. In this study, a series of hight pressure carbonation experimental factors were analyzed and discussed; they are reaction temperature, reaction time, liquid to solid ratio, stirring rate and pure CaO. In addition, a series of carbonation by simulated flue gas, the effect factors were analyzed and discussed; they are liquid to solid ratio, stirring rate, flow rate, hydrous rate of gas, gas to solid ratio. The hight pressure carbonation results showed that conversion rates and pH for BOF slag can reach to 52.5% and pH 11.15 under the conditions of reaction temperature being 25℃, CO2 pressure being 10 bar, 1 hour of reaction time, particle size less than 74μm, liquid/solid to 1 L/kg, stirring rate to 250 rpm. In addition, carbonation by simulated flue gas results showed that conversion rates and pH for BOF slag can reach to 52.29 % and pH 10.94 under the conditions of reaction temperature being 150℃, CO2 pressure being 10 %, 1 hour of reaction time, particle size less than 74μm, liquid/solid to 0.2 L/kg, flow rate to 1L/min, hydrous rate of gas to 98 %, manual stirred.