Use of magnesian fluxes of the Khalilovo deposit in sinter production

Abstract

The article describes the magnesian fluxes properties of the Khalilovo deposit with different proportions of magnesite and serpentine. The results of laboratory experiments on the effect of these fluxes with various magnesite contents on the parameters of sintering process of the Kursk magnetic anomaly ores at JSC “Ural Steel” are presented. The use of experimental magnesian fluxes of the Khalilovo deposit increases the sinter strength, yield and sinter productivity. With the use of experimental fluxes instead of Bakal siderite, an increase in the sinter yield of 3 – 5 % (rel.) can be reached. In addition, the sinter productivity increases from 1.04 to 1.08 – 1.15 t/(m2·h), that is, by 4 – 10 % (rel.). The use of experimental magnesian fluxes increases the sinter strength: the tumbler index (+5 mm) increases by an average of 4 – 6 % (abs.), and the abrasion index (–0.5 mm) decreases by 0.6 – 0.8 % (abs.). Improving the strength characteristics of the sinter using magnesian fluxes of the Khalilovo deposit is due to the formation of “reinforcing” ferritic binder, as well as due to homogenization of the solidifying melt and its crystallization in the form of glass phase of the rankinite composition, which together limit the formation of β-Ca2SiO4 . The results of experimental sintering have confirmed the possibility of using experimental fluxes in the sintering production at sinter plant of JSC “Ural Steel” without changing the production technology. The rational variant for JSC “Ural Steel” is 50 % of magnesite of Khalilovo deposit in sinter rawmix. Replacement of the Bakal siderite in the production of sinter with 2 % of MgO on the magnesian flux of the Khalilovo deposit with 50 % of magnesite provides an increase in yield by 4 – 5 %, an increase in sinter strength by 5 – 6 % and an increase in sinter productivity by 8 – 10 % while keeping the iron content at the level of the “base” period.