Steel slag and ferriferous material reprocessing process useful to produce pig iron and environmentally compatible slags

摘要

In a process for working up steel slags and iron carriers such as, e.g., electric furnace slags, converter slags, fine ores, dusts from steel production, mill scales for obtaining pig iron and environmentally safe slags, the volume ratio of molten slag to iron bath is chosen to be larger than 0.5 to 1 and, preferably, 0.8:1 to 1.5:1 and the slags are supplemented with SiO2 carriers such as, e.g., foundry sands, metallurgical sands and/or fine ores so as to adjust a slag basicity (CaO/SiO2) of between 1.0 and 1.8 and, preferably, 1.2 and 1.8 at an Al2O3 content of between 10 and 25% by weight, based on the slag. In doing so, hot blast is top-blown and coal, optionally along with an inert gas and, in particular, nitrogen and, furthermore, optionally oxygen or hot air is blown through the iron bath.