METHOD FOR REFINING FERROSILICON FROM ALUMINUM AND CALCIUM Russian patent published in 2018 - IPC C22C33/04 C21C7/00 

FIELD: metallurgy.

SUBSTANCE: invention relates to ferrous metallurgy and can be used to produce refined ferrosilicon with an aluminum and calcium content of 0.02–0.05 %. In process ferrosilicon is melted in form of screenings from fractionation of ferrosilicon fraction 0–15 mm with aluminum content of up to 2.5 % and calcium to 0.7 %, and refining is carried out with a decrease in aluminum and calcium in ferrosilicon to 0.02–0.05 %, while using as a refiner slag-forming mixture consisting of lime and an oxidizing additive in the form of iron ore pellets, iron ore concentrate or iron ore in an amount of 3–5 % of the weight of the initial ferrosilicon at the ratio of lime: oxidizing additive (1:1.5)–2.5, respectively, and fluorspar in the amount of 6–7.5 % of the weight of refining slag-forming.

EFFECT: invention allows to use a one-stage scheme for production of refined ferrosilicon using no more than two treatments with refining slag.

1 cl, 1 ex