METHOD FOR STEEL MELTING IN AN ELECTRIC ARC FURNACE WITH ACID LINING Russian patent published in 2021 - IPC C21C5/52 

FIELD: metallurgy.

SUBSTANCE: invention relates to metallurgy, in particular, to production of stainless steel in an electric arc furnace with acid lining. The slag belt of the lining is filled in layers with a mixture of quartz sand with liquid glass and powdered aluminium alloy production waste (AAPW) containing no less than 70 to 80% wt. of aluminium trioxide. Upon melting 90 to 95% of the charge, AAPW is added to the slag along the periphery of the steelmaking bath, and a material containing iron oxides and nitride-forming elements is added under the electrodes of the furnace, together with crushed waste from graphite products. In the process of complete melting of the charge, 30 to 40% of the slag is removed from the furnace by gravity. Preliminary deoxidation of the bath is executed by adding a mixture of limestone and AAPW with a content of aluminium of 65 to 75% wt. at a ratio by weight of 1:1 under the electrodes of the furnace, final deoxidation of the liquid steel is executed in a ladle of AAPW with a content of aluminium of 65 to 75% wt.

EFFECT: invention provides a possibility of involve powdered AAPW, waste from graphite products used for carburising metal, foaming furnace slag and creating a weakly reducing atmosphere in the melting space, as well as AAPW with a content of aluminium of 65 to 75% wt. in the melting process as a reducing agent for oxide phases.

1 cl, 3 ex