Factors Influencing Dephosphorization of Low Carbon Steel in Converter

Abstract:

A 300-metric ton converter in a steel plant in China was studied. The influence of factors such as slag composition and temperature in the smelting process on the dephosphorization effect was statistically analyzed. The dephosphorization ability of slag increased firstly and then decreased with the increase of temperature, basicity and FeO content. Low-temperature, high-basicity and high-oxidizing slag are thermodynamically beneficial to promote the dephosphorization reaction, but the basicity is higher than 4.0, and the temperature is higher than 1640 °C are not conducive to the slag to obtain better fluidity. At the same time, too high FeO content will increase the activity coefficient of P₂O₅, thereby increasing its activity, which is not conducive to the progress of the dephosphorization reaction. As the end point content of carbon decreases, the oxygen content increases and the phosphorus content decreases. A very low carbon content is not conducive to metal yield and temperature control.

• Periodical: Materials Science Forum (Volume 1047)
• Pages: 111-119
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.1047.111
• Online since: October 2021
• Authors: Zhao Liu*, Shu Sen Cheng, Liang Wang
• Keywords: Converter, Dephosphorization, Slag, Steelmaking

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