Development of Deep Desulfurization Technology with Premelted Slag during RH-KTB Refining

摘要

The thermophysical properties of premelted slag and synthetic slag were measured under laboratory conditions. The tests of liquid steel desulfurization using CaO-Al_2O_3-SiO_2-MgO series premelted slag and a synthetic slag have been carried out with a MoSi_2 electric resistance furnace. It was shown that the former had better desulfurization capacity than the latter. Thus, the premelted slag was chosen to be the desulfurizer for RH-KTB refining. A plant trial at a 250 ton RH-KTB unit used the premelted slag as desulfurizer and the average initial sulfur content in steel was 41.9 x 10~(-6). The results showed that the mean sulfur content in steel at the end of RH-KTB refining had decreased to 30 x 10~(-6), the lowest sulfur content was 22 x 10~(-6), and the mean desulfurization efficiency was 28.1%.