( TOPIC 9)Effects of Dephosphorization during Steel-making use Recycle Slag in different Ratio of Al2O3/SiO2

摘要

Ladle furnace slag (LF slag) is produced during refining process of steel-making. In this study, LF slag can replace lime as dephosphorizer in steel smelting process, and investigate the reusing LF slag as dephosphorizer in different ratio of Al2O3/SiO2. Based on the analysis, three kinds of refining slag have low melting point and contain suitable F-CaO which is about 7-10%. Reusing LF slag can react sufficiently and liquefy quickly in steel-making. In this method, it will not only save power, but also recycle LF slag which is difficult to handle. For different Al2O3/SiO2 proportion (0.19, 0.81, and 4.6) of refining slag in dephosphorization using induction furnace is carried out in our study. Therefore, we make 100 wt. % of LF slag as dephosphorizer, desulfurizer is 3wt.% of steel liquid, 900g of steel, and smelting for 20 minutes. The results are summarized as the followings. 1) The ratio of Al2O3/SiO2 is 0.19, the ratio of dephosphorization is 55% and the ratio of resulfurization is 35.5%. 2) The ratio of Al2O3/SiO2 is 0.81, the ratio of dephosphorization is 50.5% and the ratio of resulfurization is 91.6%. 3) The ratio of Al2O3/SiO2 is 4.6, the ratio of dephosphorization is 38.9% and the ratio of resulfurization is 87.6%. 4) The ratio of Al2O3/SiO2 is lower, the ratio of dephosphorization is higher. Reusing LF slag can efficiently reuse in the process of dephosphorization.