Sulfide Capacity of Molten CaO-SiO2-MnO-Al2O3-MgO Slags

摘要：

The sulfide capacities of the CaOSiO2MnOAl2O35wt％ MgO slags were measured at 1873 K over a wide composition range using a gasslag equilibration method. The effects of basicity and the activity coefficient of sulfide on the sulfide capacity of molten slag were also investigated based on the structural view of silicate melts. In the multicomponent silicate melts containing high MnO (up to about 50wt％), the sulfide capacity mainly increased with increasing MnO content. The capacity and modified Vee ratio, i.e. (CaO+MnO+MgO)/(SiO2+Al2O3), showed a good linear relationship. Assuming that the basicity and the stability of sulfide ions in the slag are proportional to the activity of basic oxides and the activity coefficient of sulfides, the composition dependency of the sulfide capacity is well described by changes in the aMO to 冏MS (M=Ca, Mn) ratio. The substitution of silica by alumina did not affect the sulfide capacity of the slags not only because of an increase in the activity of basic oxides but also because of a decrease in the stability of sulfides as Al2O3/SiO2 ratio increased. In the high silica melts of which silica content greater than about 30wt％, the sulfide capacity increased with increasing MnO/CaO ratio, whereas it decreased by increasing the MnO/CaO ratio in the low silica melts (< about 30wt％). This tendency of sulfide capacity resulted in the clockwisely rotating isocapacity contours in the CaOSiO2MnOAl2O3MgO system at 1873 K. The competitive dissolution mechanism of sulfur in the MnOcontaining calcium silicate melts can be explained not only by the difference in the structural role of Ca2+ and Mn2+ ions but also by the changes in the content of O2 ions according to the silica content.

关键词： Sulfide capacity CaO–SiO2–MnO–Al2O3–MgO slag Basicity Sulfide stability Silicate structure,Competitive sulfur dissolution mechanism

作者: Joo Hyun PARK Geun-Ho PARK

作者单位: School of Materials Science and Engineering, University of Ulsan, Ulsan 680-749, Korea School of Materials Science and Engineering, University of Ulsan, Ulsan 680-749, Korea Steelmaking T

会议类型: 国际会议

会议名称: Ninth International Conference on Molten Slags,Fluxes and Salts(第九届国际熔渣、溶剂与熔盐学术会议 MOLTEN12)

会议地点: 北京

会议语种:英文

页码: 1-13

在线出版日期: 2012-05-27（万方平台首次上网日期，不代表论文的发表时间）