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Considering the modern level of technological development, the efficiency for making cast iron in blast furnaces has reached its limit. The technology for improving the productivity of blast-furnace, considered in this article, consists in using high-strength partially reduced iron ore pellets, which allows cutting back the consumption of furnace coke by rapid reduction and, as a consequence, cutting back greenhouse gas emissions. According to available data, 1% of partially reduced charge pellets saves 46 cents, whereas an additional percent of metallization saves 13 cents.

The metallurgical properties of blast-furnace ore and ore-coal extrusion briquettes (BREX) based on hematite iron ore concentrate are studied. With respect to values of hot strength brex occupy an intermediate position between sinter and pellets. The reduction capacity for brex is significantly reduced with simultaneous addition of flux and solid fuel, which may be associated with a reduction in porosity (due to clogging of pores and the formation of a surface metal crust). Brex softening temperature range is largely dependent on composition and varies widely (130–330°C). The temperature range for onset of softening for all samples tested is 860–960°C. Prior softening of brex compared with sinter and pellets occurs due to a reduction in brex mechanical strength after loss of cement bonding properties (700–750°C) caused by loss of chemically bonded water and decomposition in the solid state of ferroakermanite (cement clinker component) at 775°C. It is necessary to take into account the difference in temperatures for the onset of softening of brex, sinter and pellets when selecting a multicomponent blast furnace charge. This makes it possible to avoid an increase in temperature in the cohesion zone and to reduce the zone for indirect reduction of oxides in the process of combined smelting with pellets and sinter. The data obtained make it possible to consider hematite ore based brex as a suitable blast furnace charge component.

The production of magnesia pellets is developing in mining enterprises, especially in the context of tightening environmental standards and a decrease in sinter production. In the course of the work, it was determined that from the peculiarities of pellet structure formation, the dolomite influence is manifested in a change in both the thermal conditions of firing (the endothermic effect increases with the decomposition of carbonates) and the mineral composition of the fired product. From the point of view of metallurgical properties, MgO contributes to an increase in the strength upon reduction, as well as an increase in carbonates content in the charge leads to an increase in porosity and reducibility. In general, the use of dolomite makes it possible to improve the quality of iron ore pellets by increasing their metallurgical properties.

A modernization version of OKM-520 calcining conveyor machines of AO A.V. Varichev Mikhailovskii GOK has been suggested, which is a continuation of the step-by-step comprehensive modernization of the pellet production technique at the MGOK pelletizing plant and the thermal circuit of OKM-520 calcining machines no. 1 and 2. The improvement of the technological procedure and the scheme of gas-air flows allows one to increase the productivity of the units, improve the environmental situation at the industrial site, and reduce the consumption of energy resources.

An innovative production technology for iron-ore pellets on a new generation of roasting machines is considered. The MOK-1-592M roasting machine is the basic component in the TKOM-3 pellet-production system, which went into operation at PAO Mikhailovskii GOK in 2015. The characteristics of the following products are presented: fluxed pellets of basicity 0.5; pellets based on superenriched concentrate with high iron content and low silicon-dioxide content for direct reduction; and pellets consisting of a mixture of hematite and magnetite. The production of such pellets is discussed, and the possibility of improving pellet quality at roasting machine 3 is analyzed.

The viscosities of the slags that form during the continuous converting of copper mattes and concentrates into blister copper are determined. The compositions of SiO2-CaO-Al2O3-FeOx-Cu2O-NiO slag melts are varied over a wide range of (Fe + Ni) concentrations (25.5–40.2 wt %) and ratios SiO2/CaO (0.25–3.9) and (Fe)/(Cu + Ni) (0.4–1.6). The slag viscosity is measured by a vibrational method in the temperature range 1050–1450°C. The viscosity of a homogeneous melt is shown to be 0.5–2.0 P, and it increases sharply below the primary solidification temperature.

The Gipronickel Institute in cooperation with OJSC “MMC “Norilsk Nickel” and Canadian Company Flogen Technologies Inc. has developed a new technology for continuous converting of copper-nickel mattes and copper concentrates coming from high-grade matte separation, with the production of blister copper, a slag of high copper and nickel content and gases of high SO2 concentration. A two-zone Vaniukov furnace is used as a basic reactor for this process. This work presents the basic control principles of this new technological process obtained through thermodynamic and experimental studies.

The surface tension and density of the slags that form during the continuous converting of copper mattes and concentrates into blister copper are determined. The slag melt compositions are varied over a wide range of (Fe + Ni) concentrations and SiO2/CaO and (Fe)/(Cu + Ni) ratios. The surface tension and density are measured by the bubble pressure technique. The concentration of iron and nickel in a slag and the (Fe)/(Cu + Ni) and SiO2/CaO ratios affect the density and surface tension.

The structure and liquidus temperature of the SiO2-CaO-Al2O3-FeOx-Cu2O-NiO slags that form during continuous converting of copper mattes and concentrates into blister copper are analyzed. The slag melt compositions are varied over a wide SiO2/CaO range. The slags are studied by X-ray diffraction, scanning electron microscopy, and electron-probe microanalysis. The liquidus temperature of the slags is determined by differential thermal analysis. It is found that, depending on the SiO2/CaO ratio, the structure and liquidus temperature of the slags change and the forms of copper in a slag also change. The SiO2/CaO range in a slag is recommended for the process of continuous converting of a copper nickel-containing sulfide raw materials.

The structure and liquidus temperature of the SiO2-CaO-Al2O3-FeOx-Cu2O-NiO slags that form during continuous converting of copper mattes and concentrates into blister copper in a Vanyukov furnace used as a melting unit are studied. The slag melt compositions are varied over wide limits of the total (Fe + Ni) and (SiO2 + CaO) concentrations by changing the consumption of fluxing components. The slags are investigated by X-ray diffraction, scanning electron microscopy, and electron-probe microanalysis. The liquidus temperatures of the slags are determined by differential thermal analysis. It is found that, as the consumption of fluxing components changes, the concentration of iron-nickel spinels based on trevorite NiFe2O4 changes substantially and the forms of copper change in the slags. The results obtained are used to recommend the optimum consumption of fluxing components for the process of continuous converting.