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Magnesium—strontium-containing limestones are overburden and lie together with celestite ore, the extraction of which is economically justified under their conditions of use. The results of determination of mineralogical composition of limestone, structural-phase transformations in the production of lime, iron ore agglomerate, and pellets with the introduction of limestone into the charge are given. The viscosity and refining properties of strontium-containing blast-furnace and steel-smelting slags are studied. Magnesium–strontium-containing limestones are a promising fluxing material for the sinter and steelmaking industries.

One way of increasing the smelting rate in a blast furnace is to increase the gas permeability of the lower part of the stock. Gas permeability in this zone and the smoothness of the furnace’s operation depend on the ability of the intermediate slag to filter through the coke column. A method of studying filterability has been developed and introduced, the method making it possible to reliably assess the behavior of the iron-orebearing materials in a blast furnace at high temperatures. It was established by laboratory studies and confirmed by factory tests that the filterability of molten blast-furnace slag is affected by the presence of the oxides MgO, MnO, and CaO, which are added to charge that is used to make sinter. The magnitude of this effect depends on the composition of the minerals that contain these oxides.

Prediction of the melting temperatures of pure metals, their oxides, and complex iron-ore sinter is considered. A simple formula for the energy state of solids is obtained. Other microstructural factors may be represented in the additive form of the Hall–Petch law. Alternative factors characterizing the energy state of iron-ore sinter are established. Formulas are derived for predicting the temperatures at which melting begins and ends in such sinter.

Blast-furnace smelting today is organized so as to produce low-silicon hot metal, with subsequent desulfurization. In that case, economical furnace operation is facilitated by the use of low-ash coke characterized by hot strength and low adhesion to the slag melt, as well as stable chemical composition, minimum softening temperature range, and increased melting point of the iron. The production of low-silicon hot metal with

Experimental, industrial, and computational data provide the basis for the hydrogas-dynamic theory of counterflow coke packing in blast furnaces and corresponding technology. The conversion from slag-irrigated model packing to counterflow coke packing in a blast furnace is considered. The types of residue and the motion of the material fluxes through the packing are classified. The operation of the coke packing in the blast furnace is determined in terms of the fluxes of metal, slag, residue, and gas filling the space between the coke particles.

Elements of a hydrodynamic theory of the coke packing in blast furnaces are developed, with practical applications. The static and dynamic characteristics of the slag and the coke packing are deter-mined. Regression analysis indicates the relative significance of the factors in establishing the irrigation intensity and density of coke in the packing and the hearth by slag. The formation of slag residue is also investigated in the presence external and internal sources of smelting slag and titanium (iron) slag. The optimal irrigation density of the coke packing by the slag is determined.

Physical analysis suggests an integral sintering characteristic Ksi, which may be used not only to assess batch preparation at a particular plant, since it includes the structural characteristics of the granules and the batch bed, but also for the analysis and optimization of sinter production.

The high-temperature properties of various iron ores (including washing ore) are investigated in relation to blast-furnace operation.

On the basis of experimental data for briquetting of oxidized nickel ore with a clay component mathematical models have been developed taking account of all forms of particle interaction. These equations may be used in predicting the strength of artificial structures (briquettes) prepared from fine materials. The mathematical models developed connecting factors of processed material properties with compaction parameters promote to a considerable extent solutions for questions of controlling preparation of fine materials before the widespread method of caking, i.e. briquetting. Strength formation for artificial structures is a complex process whose control may be accomplished in different production stages.

Analysis of the process of structure formation due to briquetting of fine materials with participation of a liquid phase (water) and optimization of the process with the help of a mathematical model of formation of strength in artificial structures is of considerable practical interest. Experimental studies and computations are used for constructing two mathematical models of the strength of briquettes, which allow for the composite action of three factors, namely, the diameter of the particles of the material of the structure, its moisture content, and the proportion of the mechanisms of strength formation (capillary, molecular, and propping). The models are adequate for experimental data covering the range of particle sizes from ∼0.02 to 3 mm and the range of moisture contents from WMH to W MCM. The models make it possible to predict the strength of artificial structures, i.e., briquettes, depending on the particle size of the initial material and on its moisture content within the specified range of variation of initial data.

Results are presented from a study of the operation of sinter plants operated by the Severstal’ company when finely crushed iron-ore concentrates are used in the charge. The company decided to modernize the equipment used for primary mixing, moistening, and balling of the charges in sinter plants Nos. 2 and 3. Preliminary estimates indicate that the cost of this improvement should be recovered in three years.

A method for quantitative estimation of the biocidal effect of compounds on microbial cells has been developed based on colony growth on solid nutrient media. The method allows for specifying a mode of action and for calculating the most effective ratio of biocides in synergistic blends. The test organism Serratia marcescens was grown in the presence of copper sulfate and kathon (2-N-octyl-4-isothiazolin-3-one) on agar medium supplemented with glucose and peptone. The approach made it possible to achieve respectively 96 and 67% decreases in effective concentrations of kathon and copper sulfate in the mixture.

Studies that were performed led the the following recommendations on optimizing the preparation of charges for sintering: improve the mixing (homogenization) of the charge, possibly by using high-speed paddle mixers, screw-driven pan-type mixers, or large mixing drums with a mixing coefficient of 0.95; intensify the balling of the charge in balling drums (high-intensity-rumbling regime); optimize moistening by using fine-spray water nozzles that employ compressed air; introduce automation systems at the stages of primary mixing and balling (high-intensity-rumbling regime), as well as moistening.

Initial stages of corrosion of mild steel induced by Klebsiela rhinoscleromatis BO2 were studied in various media. The effect of the microorganism was detected 8–10 h after inoculation. The number of viable cells was virtually unchanged over one month in all media, but the corrosive activity of the strain decreased. The corrosive activity of microorganisms can be determined by spectrophotometry even after incubation for only 24 h. At a low level of organic substrate, even strong colonization with microorganisms does not inevitably result in significant damage to metals.

An ultrasonic method is used to study the onset of ion transport inlithium oxides in a ceramic of the Li-Si-Ge-As-S-O system. The onset temperature for ion transport estimated from the temperature dependence of the relative change in the propagation speed of ultrasound is the same as that obtained by other methods, which indicates that the ultrasonic method is applicable to studies of the onset of ion conductivity inlithium oxide semiconductors.

We obtain relations between the dielectric permittivity and the density of monatomic and polyatomic nonpolar dielectrics in the gas and liquid states. The relations lead to a constant value of the polarizability of atoms and molecules over a wide range of the state parameters.

An analysis of the magnetization processes in magnetic films must take into account the fields arising from the nonuniformity of the film magnetization. Equations are obtained involving the fields of magnetic poles distributed over the film surface. These equations are applicable to continuous films as well as to separate magnetic thin film strips. The magnetization distribution is determined for a hard direction field by a numerical solution of the basic integro-differential equations. [Russian Text Ignored].