Advanced Modeling of Slag Foaming and Its Industrial Applications for Energy Conservation in Electric Arc Furnaces

Abstract

Suitable foaming slag is beneficial for improving electricity utilization efficiency and reducing the electricity consumption of electric arc furnaces. One key factor determining the foaming performance of slag is the presence of certain solid particles. Additionally, the MgO content in the slag must reach saturation to minimize the consumption of refractory materials. In this study, based on the CaO-SiO₂-MgO-FeO slag system and calculations using FactSage 8.3 software, the saturation of MgO and its influence on the foaming properties of slag were investigated. An isothermal saturation diagram and a ternary isothermal cross-section diagram were constructed to compare the foaming properties of slag under different conditions. The relationship between electricity consumption and the foaming properties was verified by industrial test. The results showed that MgO saturation decreases with increasing slag basicity and increases with rising temperature. The effect of FeO content on MgO saturation was more significant at low basicity (B₂ ≤ 1.6) than at high basicity (B₂ > 1.6). Compared to slag outside the optimal foaming range, the average electricity consumption of slag with saturated MgO within the optimal foaming interval was reduced from 350.57 kWh/ton to 333.12 kWh/ton.