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Purging plugs are commonly used in the secondary refining process, which determines the fluid hydrodynamics and refining effects of the ladle. This study proposes a blowing approach to enhance flow field disturbance and mass transfer. The experiment, designed to validate the numerical simulation, involved the use of UDF (user-defined function) to describe bubble expansion and the variation of gas blowing. The results indicated that the pulsed bottom blowing method was more effective in producing tiny bubbles. Owing to the smaller fluctuation amplitude for the pulsed bottom blowing, the energy dissipated by slag layer fluctuations decreases. Compared to the pulsed bottom blowing, the proportion of the slag eye area of the steady bottom blowing is 12 pct larger. Furthermore, the pulsed bottom blowing causes an intermittent flow field. This discontinuity stirring energy input is conducive to its transmission and dissipation. Besides, the mixing time of pulsed bottom blowing exceeds 5 pct larger than that of the steady bottom blowing. These findings have practical implications for enhancing the flow hydrodynamics of liquid steel and controlling bubble diameter by the purging plug within the pulsed bottom blowing in the ladle, which is also suitable for stirring reactors with gas blowing. [ABSTRACT FROM AUTHOR]

To predict slag corrosion numerically, a transient 3D mathematical model that considers the fluid flow, heat, and mass transfer was developed. A dynamic corrosion experiment using the rotating immersion approach was carried out to assess the overall corrosion activation of the MgO-C refractory. An expression for the corrosion rate was determined based on the wall shear stress, slag viscosity, sample size, overall corrosion activation, and difference in MgO content. A greater corrosion rate was observed at the bottom corner of the refractory sample compared to other parts, and it was concluded that higher temperatures and speeds encourage slag corrosion. The averaged corrosion rates at the sample wall with different rotating speeds and holding periods were compared. The relative error varied from 1.92% to 12.19%, which is within the acceptable range. It is expected that the proposed computational framework can be potentially extended to other refractory corrosion scenarios in metallurgical reactors. [ABSTRACT FROM AUTHOR]

[Display omitted] • The combustion of a mixed fuel (80%PC&20%SPL) in raceway was studied numerically. • The mixed fuel is proved to be an alternative of pure PC for carbothermal reduction. • The use of mixed fuel will reduce the carbon emission in the iron making industry. This study investigated the potential use of spent pot-lining (SPL) as a supplementary fuel in blast furnaces (BFs) to replace coke or pulverized coal (PC). A numerical model was established to study the combustion behavior of mixed fuel (MF) containing 80 % PC and 20 % SPL in the raceway of BF. The study focused on the effects of blast velocity, temperature, injection rate, and oxygen content on combustion. Results showed that the burnout rate has a positive relationship with blast velocity and oxygen content, and decreases with the increase of blast temperature and injection volume. To obtain a high temperature zone, it is recommended to increase the oxygen content and air volume of the blast, and the blast temperature (1473 K) and injection volume (169 kg/t) maintain the basic operating conditions. These results can provide insights into the potential use of SPL as a waste resource in iron-making processes, which can promote the substitution of industrial waste SPL for PC in high-energy-consuming industries, contribute to the development of green metallurgical technology, and advance global energy conservation and emission reduction techniques. [ABSTRACT FROM AUTHOR]