Analysis of the current technical solutions for the processing of iron ores showed that the high-grade ores are directly exposed to metallurgical processing; by comparison, low-grade ores, depending on the mineralogical and material composition, are directed to beneficiation including gravitational, magnetic, and flotation processes or their combination. Obtaining high-quality concentrates with high iron content and low content of impurities from low-grade iron ores requires the maximum possible liberation of valuable minerals and a high accuracy of separating features (difference in density, magnetic susceptibility, wettability, etc.). Mineralogical studies have established that the main iron-bearing mineral is hematite, which contains 69.02 to 70.35% of iron distributed in the ore. Magnetite and hydrogoethite account for 16.71–17.74 and 8.04–10.50% of the component, respectively; the proportion of iron distributed in gangue minerals and finely dispersed iron hydroxides is very insignificant. Iron is mainly present in the trivalent form—Fe 2 O 3 content ranges from 50.69 to 51.88%; bivalent iron is present in small quantities—the FeO content in the samples ranges from 3.53 to 4.16%. The content of magnetic iron is 11.40–12.67%. Based on the obtained results by the investigation of the features of magnetite–hematite ores from the Mikhailovskoye deposit, a technological scheme of magneto-flotation beneficiation was proposed, which allows producing iron concentrates with 69% of iron content and less than 2.7% silicon dioxide for the production of pellets with subsequent metallization.

Deterioration of mineralogical and physical characteristics of mineral raw materials results in the formation of the primary task for the comminution processes—reduction in the size of ore to obtain a material with a certain granulometric composition, which in turn is achieved by overgrinding of raw materials and, consequently, an increase in energy costs. The work aimed to justify the possibility of selective disintegration of mineral assemblages of polymetallic ores of various genesis at the stage of crushing based on in-depth investigation and revealing of interrelation and mutual influence of mineralogical-geochemical features, textural-structural and technological properties. Structural and textural features have been studied by the methods of computed X-ray microtomography. Experimental and theoretical investigations of mineralogical and technological parameters of raw materials, as well as research on crushing using different types of crushers, made it possible to substantiate the possibility of selective disintegration for polymetallic ores.

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The mining industry is faced with the problem of depletion of reserves of easily beneficiated minerals containing valuable metals. The characteristic features of the ores involved in processing are fine dissemination; low content of valuable components; and similar physical, chemical, surface, and technological properties of minerals, among others. Under such conditions, increasing the efficiency of mineral processing becomes of primary importance. Creating highly efficient, environmentally safe technologies on the basis of deep study of the material, chemical, and mineralogical composition, as well as using and developing methods and techniques for testing mineral materials at successive stages of raw material transformation, enable to solve such problems. Criteria for assessing the flow of technological processes are presented in the article. A complex criterion is substantiated and proposed for quantitative assessment of the degree of physical and energy impact at the stages of ore preparation and flotation enrichment of mineral raw materials. The criterion is calculated on the basis of activation energy data calculated by differential and integral kinetic methods. In addition, an empirical indicator was introduced into the complex criterion, which allows increasing the accuracy of the calculated criterion. This criterion not only allows to estimate the degree of influence from the position of averaged estimation on the full interval of degrees of transformation from 0 to 1, but also gives the possibility to consider the required number of degrees of transformation; for example, if it is necessary to make estimations on narrow temperature intervals. The calculation of empirical parameters for the obtained criterion is carried out before and after the application of physical–energetic methods of influence using thermal analysis.

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