Properties of boron-rich slag separated from boron-bearing iron concentrate

Abstract

In the present paper, the fundamental research on the properties of boron-rich slag melting separated from boron-bearing iron concentrate was performed. The melting and fluidity of B₂O₃-MgO-SiO₂-FeO slag system, crystallization of separated boron-rich slag and factors on the extraction efficiency of boron-rich slag were systematically investigated. B₂O₃ content would heavily affect the melting and fluidity property of boron-rich slag. Generally, FeO could improve the melting and fluidity property of boron-rich slag. Boron-containing crystalline phase mainly precipitated in temperature range from 1200 °C to 1100 °C. Higher smelting temperature and B2O3 reduction ratio were negative for the extraction of boron. The cooling rate of 10–20 °C/min was better for the crystallization of boron-containing crystalline phase. Based on the obtained experimental results, the optimum operating parameters for the development of pyrometallurgical boron and iron separation process and further boron-rich slag cooling process were proposed.

Keywords

boron-bearing iron concentrate / boron-rich slag / melting / fluidity / crystallization

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