This study describes the characteristics of mineral wool and its applications,and also introduces the traditional process of mineral wool made from molten blast furnace (BF) slag. Compared with high energy consumpti...This study describes the characteristics of mineral wool and its applications,and also introduces the traditional process of mineral wool made from molten blast furnace (BF) slag. Compared with high energy consumption of the traditional process,the production of mineral wool by using molten BF slag will be able to take full advantage of the sensible heat of molten slag, and also reduce production costs. However, there are also further issues to resolve such as how to obtain the required amount of molten BF slag and how to make it homogeneous. Based on the physical and chemical properties of the molten BF slag,the investigation into the relationship between temperature and viscosity under different acidity coefficients of the slag and silicon mixture was conducted. Combined with the crystallization and phase diagram of slag wool, its heat resistance, water resistance, durability and corrosion resistance were analyzed. Finally, trends of the technology development are proposed.展开更多
Activity of TiO_2 in the molten blast furnace slag containing TiO_2 has been examined at 1500℃ by means of “molten slag-Sn” chemical equilibrium method,using metallic Sn as flux and graphite as deoxidizer,together ...Activity of TiO_2 in the molten blast furnace slag containing TiO_2 has been examined at 1500℃ by means of “molten slag-Sn” chemical equilibrium method,using metallic Sn as flux and graphite as deoxidizer,together with phase diagram caIculation.In the pentary slag system CaO-MgO-SiO_2-TiO_2-Al_2O_3,a_(TiO_2)=0.01—0.05 or 0.02—0.10 with pure liquid or solid TiO_2 as standard state,respectively.The activity and activity coefficient of TiO_2 in relation to concentration of TiO_2 have been discussed.展开更多
We report the adsorption of phosphate and discuss the mechanisms of phosphate removal from aqueous solution by burst furnace slag (BFS) and steel furnace slag (SFS). The results show that the adsorption of phosphate o...We report the adsorption of phosphate and discuss the mechanisms of phosphate removal from aqueous solution by burst furnace slag (BFS) and steel furnace slag (SFS). The results show that the adsorption of phosphate on the slag was rapid and the majority of adsorption was completed in 5~10 min. The adsorption capacity of phosphate by the slag was reduced dramatically by acid treatment. The relative contribution of adsorption to the total removal of phosphate was 26%~28%. Phosphate adsorption on BFS and SFS follows the Freundlich isotherm, with the related constants of k 6.372 and 1/n 1.739 for BFS, and of k 1.705 and 1/n 1.718 for SFS. The pH and Ca2+ concentration were decreased with the addition of phosphate, suggesting the formation of calcium phosphate precipitation. At pH 2.93 and 6.93, phosphate was desorbed by about 36%~43% and 9%~11%, respectively. These results indicate that the P adsorption on the slag is not completely reversible and that the bond between the slag particles and adsorbed phosphate is strong. The X-ray diffraction (XRD) patterns of BFS and SFS before and after phosphate adsorption verify the formation of phosphate salts (CaHPO4·2H2O) after adsorption process. We conclude that the removal of phosphate by BFS and SFS is related to the formation of phosphate calcium precipitation and the adsorption on hydroxylated oxides. The results show that BFS and SFS removed phosphate nearly 100%, indicating they are promising adsorbents for the phosphate removal in wastewater treatment and pollution control.展开更多
XRD,TEM,ED,and NMR analyzed four types of blast furnace slags (BFS) with different structures in this paper. The composition requirement for phase separation in BFS glass phase was then put forward,that is the composi...XRD,TEM,ED,and NMR analyzed four types of blast furnace slags (BFS) with different structures in this paper. The composition requirement for phase separation in BFS glass phase was then put forward,that is the composition of slag locates in the coexisting phase region of melilite and any silicate mineral with Q0 units. The special structure of melilite units,a 5-membered ring with high degree of polymerization (DOP),plays a key role in the formation of phase separation. In BFS system,one with chemical composition of larger ratio of (CaO + MgO/(SiO2 + Al2O3) would be more promising to meet the requirement for phase separation.展开更多
文摘This study describes the characteristics of mineral wool and its applications,and also introduces the traditional process of mineral wool made from molten blast furnace (BF) slag. Compared with high energy consumption of the traditional process,the production of mineral wool by using molten BF slag will be able to take full advantage of the sensible heat of molten slag, and also reduce production costs. However, there are also further issues to resolve such as how to obtain the required amount of molten BF slag and how to make it homogeneous. Based on the physical and chemical properties of the molten BF slag,the investigation into the relationship between temperature and viscosity under different acidity coefficients of the slag and silicon mixture was conducted. Combined with the crystallization and phase diagram of slag wool, its heat resistance, water resistance, durability and corrosion resistance were analyzed. Finally, trends of the technology development are proposed.
文摘Activity of TiO_2 in the molten blast furnace slag containing TiO_2 has been examined at 1500℃ by means of “molten slag-Sn” chemical equilibrium method,using metallic Sn as flux and graphite as deoxidizer,together with phase diagram caIculation.In the pentary slag system CaO-MgO-SiO_2-TiO_2-Al_2O_3,a_(TiO_2)=0.01—0.05 or 0.02—0.10 with pure liquid or solid TiO_2 as standard state,respectively.The activity and activity coefficient of TiO_2 in relation to concentration of TiO_2 have been discussed.
基金Project supported by the Foundation for the Author of NationalExcellent Doctoral Dissertation of China (No. 200149)the NaturalScience Foundation of Zhejiang Province (No. R305078), China
文摘We report the adsorption of phosphate and discuss the mechanisms of phosphate removal from aqueous solution by burst furnace slag (BFS) and steel furnace slag (SFS). The results show that the adsorption of phosphate on the slag was rapid and the majority of adsorption was completed in 5~10 min. The adsorption capacity of phosphate by the slag was reduced dramatically by acid treatment. The relative contribution of adsorption to the total removal of phosphate was 26%~28%. Phosphate adsorption on BFS and SFS follows the Freundlich isotherm, with the related constants of k 6.372 and 1/n 1.739 for BFS, and of k 1.705 and 1/n 1.718 for SFS. The pH and Ca2+ concentration were decreased with the addition of phosphate, suggesting the formation of calcium phosphate precipitation. At pH 2.93 and 6.93, phosphate was desorbed by about 36%~43% and 9%~11%, respectively. These results indicate that the P adsorption on the slag is not completely reversible and that the bond between the slag particles and adsorbed phosphate is strong. The X-ray diffraction (XRD) patterns of BFS and SFS before and after phosphate adsorption verify the formation of phosphate salts (CaHPO4·2H2O) after adsorption process. We conclude that the removal of phosphate by BFS and SFS is related to the formation of phosphate calcium precipitation and the adsorption on hydroxylated oxides. The results show that BFS and SFS removed phosphate nearly 100%, indicating they are promising adsorbents for the phosphate removal in wastewater treatment and pollution control.
基金supported by the National Natural Science Foundation of China (Grant No.50954004)the National Science & Technology Pillar Program of China (Grant No.2007AA03Z529)
文摘XRD,TEM,ED,and NMR analyzed four types of blast furnace slags (BFS) with different structures in this paper. The composition requirement for phase separation in BFS glass phase was then put forward,that is the composition of slag locates in the coexisting phase region of melilite and any silicate mineral with Q0 units. The special structure of melilite units,a 5-membered ring with high degree of polymerization (DOP),plays a key role in the formation of phase separation. In BFS system,one with chemical composition of larger ratio of (CaO + MgO/(SiO2 + Al2O3) would be more promising to meet the requirement for phase separation.