Equilibrium between molten CaO-based slags and iron alloys and activities of slag components

熔融CaO基炉渣与铁合金之间的平衡及炉渣成分的活性

• 批准号: 61550495
• 负责人: FUJISAWA Toshiharu
• 金额: $ 1.28万
• 依托单位: Nagoya University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1986
• 资助国家: 日本
• 起止时间: 1986 至 1988
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-61550495/
• 关键词: Molten slag; Activity; Equilibrium; Calcium aluminate; Ultra clean steel; カルシア

Calicia-based slags play an important role in the ladle deoxidation and desulfurization process, particularly in the production of clean steel. The CaO-Al_2O_3 system is one of the fundamental systems of the calcia-based slags, and there have been many reports on the thermodynamics of this system. However, a great discrepancy is apparent among these reports.Difficulties may be anticipated in the precise determination of the activities of the components in steelmaking slags at high temperature. Instead of measuring the absolute value of the activity of each component, measurement of the activity ratio may make the experiment much easier.On the other hand,one of bottle necks of the experimental study in the high temperature physical chemistry may be crucible materials. To avoid the sample contamination by crucible materials and the effect of the crucible materials on the reactions concerned, high temperature resistance inert materials are required.In the present experiment, on the contra … More ry, CaS crucibles were manufactured, and CaO-AlResearcho@>D2O<@D23@>Dag and molten iron alloy were brought into equilibrium with the crucible at 1600 c. Therefore, CaS took part in the chemical reactions.The equilibrium relation between the slag and molten iron alloy can be represented by the equation: 3CaO + 2Al + 3S = 3CaS + Al_2O_3, and the product of the activities of aluminum and sulfur in molten iron alloy (hA1^2・hs^3) has a constant value for a fixed slag composition.By application of the Gibbs-Duhem equation, integration techniques have been developed which allow the activities of CaO and Al_2O_3 in the slags to be determined from the relation between (hA1^2・hs^3) and the slag composition. In the activity calculation, any thermodynamic data are not required except the phase diagram of the CaO-Al_2O_3 system and the activity coefficients of aluminum and sulfur in molten iron, those have relatively high accuracies. Therefore, the activities of CaO and Al_2O_3 could be determined without any accumulation of inaccuracies in the use of any other thermodynamic data. Less

钙基渣在钢包脱氧脱硫过程中起着重要作用，特别是在洁净钢生产中。CaO-Al_2 O_3系是钙基渣系的基本体系之一，有关该体系的热力学研究已有许多报道。然而，这些报告之间存在着很大的差异，在高温下精确测定钢渣中各组分的活度可能会遇到困难。用活度比代替活度的绝对值，可以使实验变得容易，但坩埚材料可能是高温物理化学实验研究的瓶颈之一。为了避免坩埚材料对样品的污染以及坩埚材料对反应的影响，需要使用耐高温的惰性材料。 ...更多信息 制造CaS坩埚，并使CaO-AlResearcho D2 O D23 Dag和熔融铁合金在1600 ℃下与坩埚达到平衡。因此，CaS参与了化学反应，渣与铁液之间的平衡关系可用下式表示：3CaO + 2Al + 3S = 3CaS + Al_2O_3，是铝和硫在铁液中活度的乘积（hA1^2·hs^3）对于固定的炉渣成分具有恒定值。利用（hA1^2·hs^3）与炉渣组成的关系，可以确定炉渣中CaO和Al_2O_3的活度。在活度计算中，除了CaO-Al_2 O_3系相图和铁液中铝、硫的活度系数外，不需要任何热力学数据，具有较高的精度。因此，用其它热力学数据测定CaO和Al_2O_3的活度时，不会积累任何误差。少

项目成果

藤澤敏治: 鉄と鋼. 75. (1989)

藤泽敏晴：铁到羽金 75。（1989）

Toshiharu Fujisawa: "Equilibrium between CaO-Al_2O_3-CaSsat. slags and molten iron alloys" Tetsu-to-Hagane. 75. (1989)

Toshiharu Fujisawa：“CaO-Al_2O_3-CaSsat.炉渣和铁水合金之间的平衡”Tetsu-to-Hagane。