Water Capacity Model of Al₂O₃‐CaO‐MgO‐SiO₂ Quaternary Slag System

Abstract

The focus of the present work was to develop a water capacity model for the quaternary slag system AI 203-CaO-MgO-Si02. In the model, a silicate melt was considered to consist of two ion groupings, viz. cation grouping and oxygen ion. The water capacity of a melt is supposed to depend on the interactions between the cations in the presence of oxygen ions. These interactions were determined on the basis of the experimentally measured water solubility data. Only binary interactions were employed in the model. For the system CaO-Si0 2, disagreement in the literature data was found. Since the interaction between Ca 2 + and Si 4 + would play an important role, experiments were carried out to determine the water capacities of some CaO-Si0 2 slags. For this purpose a thermogravimetric method was employed. Iso-lines of water capacities at constant MgO contents were predicted by the model and compared with the experimental data from literature. The model calculations agreed well with the experimental results.

Sulfur Distribution between Liquid Iron and Magnesia-Saturated Slag in H2/H2O Atmosphere Relevant to a Novel Green Ironmaking Technology

“…Also, the L S values for the blast furnace operation will be compared with those under the conditions of the proposed process. From previous research, water has a significant solubility in slag, indicating that it could affect L S . This made it difficult to obtain predictions using any of the available models since none of them included the effect of water solubility in slag.…”

“…On the other hand, water was found ,− to have a significant solubility in both basic and acidic slags. In basic slags, water may exist as free OH – according to the following reaction: normalH 2 normalO ( g ) + normalO 2 − = 2 OH − In acidic slags the reaction may be which breaks an oxygen bridge in the silica anion network.…”

Phosphorus Distribution between Liquid Iron and Magnesia-Saturated Slag in H2/H2O Atmosphere Relevant to a Novel Ironmaking Technology

“…Second, it could be attributed to the fact that all these correlations did not consider H 2 and H 2 O interaction with the slag. Previous research − has shown that water has a significant solubility in slag in the temperature range of 1500–1650 °C. In basic slags, water may form free OH – according to the following reaction: normalH 2 normalO ( g ) + normalO 2 − = 2 OH − In acidic slags, water dissolution may involve the following reaction: which breaks an oxygen bridge in the silica anion network.…”

Hydrogen pick-up after vacuum degassing

“…13 The water capacity model considers a silicate melt that consists of cation grouping and oxygen ions. The water capacity is assumed to depend on the binary interactions between the cations in the presence of oxygen ions.…”

“…For this purpose, sampling of liquid slag and steel were carried out at different stages during ladle treatment at SSAB, Oxelo ¨sund, Sweden. These data were analysed along with the data of moisture level with the help of the water capacity model developed by Brandberg et al 13…”