Vol 32 Iss. 3

Honored Worker of Science and Technology, Doctor of Technical Sciences, Professor of the Leningrad Mining Institute K. F. Beloglazov was born on November 13, 1887 in Kamyshin, Saratov Province, in the family of a clerk. He graduated from a real school in Penza, and then entered the St. Petersburg Mining Institute. Here began the scientific work of the future scientist. While still a student (1911) he developed the methodology of quantitative chemical analysis. His diploma work - Melting diagram and microstructure of copper-antimony alloys was awarded the prize of K. I. Lisenko and published in parts. By the decision of the Institute Council K. F. Beloglazov was retained at the Institute as an assistant to Academician N. S. Kurnakov at the Department of Analytical Chemistry. Scientific creativity of K. F. Beloglazov was directed to the solution of the largest problems of the national economy. Thus, his most characteristic works are the following: physicochemical analysis, chemical technology and chemical analysis, quantitative chemical and mineralogical analysis and physical chemistry of mineral enrichment processes. The List of works of K.F. Beloglazov is enclosed.

For more than a quarter of a century it has been incessantly said about the lag between the theory of the flotation process and its practice. All figures in the field of flotation know it. However, until now none of the enrichers has put and tried to solve the question about the reasons of such an unacceptable and harmful situation. My report is intended to give an overview of the history of development and the state of the question of the theory of flotation abroad. At the same time, at the end of the report I will allow myself as a prerequisite for the next report to make some conclusions about the ways in which the domestic flotation science should move in order to rise to a height that meets the requirements of our remarkable era. I do not know if there is a more striking example than flotation of the way in which in the capitalist world science is being made an instrument of profit by certain powerful financial groups.

By a theory of the flotation process we will conditionally understand only such a concept which, accepting at least a hypothetical but probable explanation of the basic mechanism of the process, makes it possible to predict quantitatively with greater or lesser accuracy the course of the flotation process in time when its conditions change or when one or more of the links constituting the process are affected. Only such a theory will allow to consciously manage the process in the factory and to reduce to a minimum the number of control experiments. The only criterion for the correctness of such a theory can only be the quantitative coincidence of the prediction with the facts of practice, i.e. the results of flotation experiments. My book and represents an attempt to build such a theory of the process, so I gave it the subtitle Experience of the theory of the flotation process. I shall dwell only on some sections of the book and describe in more detail the path that led me to the hypothesis of the molecular mechanism of particle attachment to the bubble.

In the development of flotation enrichment the Soviet industry has had tremendous achievements. With the rapid development of practice, the lag of theory is particularly acute. Anyone who is directly involved in the study of ores for enrichability or the solution of practical problems in the field of enrichment, is well aware that even in laboratory conditions for each new more or less complex object of study the solution has to be sought by torturous experimentation. In most cases there is no theoretical justification of the solution found. The lag between theory and practice is largely due to the fact that the pace of development of theoretical work still does not match the pace of development of industry, and the direction of theoretical work is not related to the nodal iss.s of practice. The shortcomings of theoretical works in the field of flotation include: lack of planning, lack of sharp criticism, insularity and leaving the field of flotation theory to professional theorists, sometimes disconnected from practice. The present discussion should help to eliminate these deficiencies as quickly as possible, to help choose the right path for further progress.

In March and April 1951, a seminar-discussion on the theory of flotation was held at the Leningrad Mining Institute. The seminar was attended by about 140 people representing 15 scientific organizations. Six sessions were held, at which three papers were heard and discussed: К. F. Beloglazova - Historical review of the development of the theory of flotation process abroad; К. F. Beloglazova - Basic regularities of the flotation process; С. I. Mitrofanova - Current state of the theory of flotation process. The liveliest discussion unfolded on the second report of K. F. Beloglazov. In the speeches was given a general assessment of the book by K. F. Beloglazov Laws of the flotation process, made a number of critical comments on some sections of the work and outlined further ways of development of research on the theory of the flotation process. A systematic presentation of the discussion on this work is given in an abbreviated form. At the end of the review there is a concluding word of Prof. K. F. Beloglazov, in which the questions not resolved in the discussion are clarified.

The present state of our knowledge of the free surface energy (surface tension) of even simple binary solutions cannot be recognized as orderly. This state of theory is aggravated by the anarchically disordered state of experimental data. The abundance of methods for determining surface tension, until now mutually uncorrected, make all the huge accumulated now and continuously increasing material of experiments completely unsuitable for verifying any conclusions or, what is worse, suitable for confirming any deduced equation. Up to the present time there is no independent method, other than the simple comparison of results usually adopted, by which the results obtained by experiments can be corrected. The object of the present work is to derive a general equation for the free surface energy of binary solutions, and to find a method of testing the fairness of experimental data for determining the surface tension.

D. I. Mendeleev as early as 1860 pointed out the existence of a simple relationship between the composition of liquids and the value of the capillary constant. His equation expressing the molecular cohesion of a liquid as the doubled product of surface energy (tension) by molecular weight was the first of a large number of equations expressing the same idea. Twenty-six years later, R. Eötvösch, based on van der Waals' doctrine of corresponding states, found an equation relating liquid composition, temperature, and surface free energy (see article). By means of this equation, as R. Eötvösch pointed out, it is possible to compare the states of molecules in vapors and in liquids by the magnitude of the deviations of the universal constant from the universal value.

The results of flotation of oxidized copper ores at a given mineralogical composition are mainly determined by the selected conditions of preliminary sulfidization of the ore. Conscious management of this operation at the factory requires clear ideas about the kinetics of the process of interaction between soluble sulfides and copper carbonates, about the influence of the sulfide layer on minerals on the subsequent process of their interaction with xanthates, etc. Detailed studies of the sulfidization process, carried out in the laboratory of general and physical chemistry of the Leningrad Mining Institute, on the example of malachite characterized: 1) kinetics of interaction between soluble sulfides and malachite; 2) influence of electrolytes on the sulfidization process; 3) kinetics of interaction between xanthates and malachite - natural and sulfidized; 4) flotation of malachite using different sulfidizers, etc. The results of the study are of interest for industrial flotation of ores containing oxidized minerals, since the processes of interaction between such minerals and flotation reagents have not yet received sufficient coverage in the literature.

In a significant part of gold-bearing deposits of the Soviet Union the main ore minerals are iron sulfides - pyrrhotite and pyrite. Therefore, it is of undoubted interest to study the behavior of these minerals in alkaline cyanide solutions used to extract gold from ore. There is a widespread opinion among gold industry workers that the main reason for high potassium cyanide consumption in the treatment of some ores or extreme duration of this treatment is the presence of pyrrhotite. However, there are no detailed studies on the behavior of pyrrhotite during cyanidation. The present work presents the results of studying the kinetics of interaction of pyrrhotite of one of gold-bearing deposits with potassium cyanide solution, the composition of which is close to those usually used in industry. The work done allowed us to suggest the mechanism of interaction of pyrrhotite with potassium cyanide solution under different conditions, and on this basis to propose ways to reduce the consumption of cyanide.

Cast antimony electrode is one of the few indicator electrodes convenient for continuous control of the pH of pulps during flotation of various ores. The wide application of this electrode in production conditions is hindered to some extent by the lack of clear ideas about the mechanism of action of electrodes, because without this it is very difficult to establish the conditions of their normal operation. On the basis of the values of experimentally obtained potentials, as well as chemical properties of elements of arsenic subgroup, an attempt has been made to elucidate chemical processes occurring on metal-oxide electrodes (elements of arsenic subgroup) in aqueous solutions. As a result, electrode reactions (interaction of hydrate film on the electrode with ions of aqueous solution) are given. The influence of temperature on the readings of arsenic, antimony and visutite electrodes was determined and the heat effects of chemical processes occurring at these electrodes were calculated. The obtained values of thermal effects confirm the correctness of the proposed electrode reactions.

Evaluation of the stability of readings of a number of metal-oxide electrodes in measuring the pH of solutions was aimed at obtaining data for the selection of the most reliable electrode from the metals of the arsenic subgroup, as well as establishing the methodology of calibration of these electrodes. The electrochemical properties of arsenic, antimony and bismuth electrodes were tested by measuring potentials by the compensatory method. The arsenic electrode gives continuously increasing readings during the whole time under all the above test conditions. When solutions are stirred, it begins to dissolve noticeably, and in the presence of solid phase in the solution, it gradually breaks down. This makes the arsenic electrode unsuitable as an indicator electrode. Antimony electrode gives the most stable readings in solutions under stirring, especially with continuous mechanical cleaning of its surface. The bismuth electrode readings are also most stable in solutions when stirred in the presence of a solid phase.

Reduction by successive division into two more or less equal parts is a common operation in mineral sampling. The weight limit to which a particular material can be reduced depends on the particle size distribution, the content of the component to be determined (useful), the magnitude and degree of irregularity of the phenocrysts of that component in the host rock, the specified accuracy of reduction, and the degree of confidence in obtaining a sample with the specified accuracy. However, until recently, the mathematical dependence of the reduction weight limit on these parameters has not yet been established, although this iss. has been occupying the attention of specialists for many years. In the present work the results of experimental and theoretical researches are stated, which allowed to establish the regularity of distribution of mineral grains in the parts allocated by reduction and to find the mathematical dependence of the limiting weight of reduction (sample weight) on the main features of the sampled mineral.

Equations of coarseness characterization are increasingly widely used in solving practical problems related to the sampling and beneficiation of ores. Of the considerable number of mathematical expressions proposed, the equation of Prof. S. E. Andreev (see article) and the Rosin-Rammler exponential equation (see article) are the most widely used. Equations (1) and (2) are convenient for practical calculations, but they show good agreement with experience only for small size classes of grinding products. When it is necessary to estimate the particle size distribution of the largest fractions of the product, these equations are of comparatively little use. Equations (1) and (2) are so simple and coincide so well with experience for small values of x that it seemed natural to make an attempt to improve them in such a way that the area of application of these equations was expanded and their positive qualities were preserved. A possible solution of this problem is given below.

In sulfide copper-nickel ores, as is known, there are always noble metals-silver, gold, and platinoids. Platinoids are of special importance - their value in some cases may be equal to copper and nickel. This makes it necessary to include special operations related to the extraction of noble metals in the processing of copper and nickel ores. Practice has shown that noble metals in the pyrometallurgical process follow the metal-containing product, i.e. in the course of copper-nickel ore processing they are sequentially concentrated in matte and high-grade matte. It is believed that the separation smelting process also separates noble metals into two groups: 1) gold and silver mainly follow copper; 2) platinoids follow nickel. Thus, already at the first stage of pyrometallurgical processing - in ore smelting - noble metals are selectively concentrated in the sulfide phase (matte) preferably before the silicate phase (slag). The nature of this phenomenon has not been accurately established until now. In the present work an attempt is made to reveal the reason for the concentration of noble metals in sulfides during ore smelting of copper-nickel ores and in the subsequent stages of pyrometallurgical processing - during conversion of copper-nickel matte and separation smelting.

As the gold mining industry develops, the processing of primary ores, among which sulfide ores are becoming more and more important, is increasing every year. On the other hand, in the beneficiation of non-ferrous metal ores, some gold is lost in sulfide flotation tailings and to recover it, in some cases these tailings must be subjected to additional hydrometallurgical treatment by cyanidation. The practice of modern gold recovery plants shows that in many cases sulphide ores and concentrates are resistant to hydrometallurgical treatment. Attempts to extract such gold from sulphide concentrate by conventional hydrometallurgical routes are often very inefficient. Despite the use of intensive repeated treatment, the residual gold content in tailings is very high and in some cases reaches 20-25 g/t. All this requires a more in-depth analysis of the reasons for the persistence of gold associated with sulfides. The proposed work aims to summarize and analyze the results of the study of some sulfide (pyrite and pyrrhotite) ores. Most of the experimental studies used in this paper were obtained during technological tests of the treatment of gold-bearing pyrite and pyrrhotite ores in the metallurgical laboratory of the Mining Institute in 1950- 1953.

The main task of phase analysis in the evaluation of minerals as objects of technological processing is to find out what minerals are represented and how quantitatively distributed between them valuable metal. No less important is the quantitative assessment of the useful component, which is in the state of fine dispersion in the host rock, or undesirable (harmful) impurity in the composition of the ore mineral itself. Often encountered in the practice of such studies various forms of interrelation of mineralogical components also need to be defined and quantitatively accounted for. Phase analysis also includes the question of the forms and degree of metal content of individual components of ore raw materials. Clarification of the material composition of fossils, even for relatively simple objects is done more often by applying chemical rational analysis. The question of the forms and degree of metal content of individual components of the ore is quantitatively solved also mainly by the chemical method of research. Chemical methods of determination of metal content allow to take into account also those components of the mineral, which contain in one or another form of valuable metal, but at the same time are not compounds of this metal. Quantitative assessment of the degree of metal content of such components complements the material composition of the object under study, correctly directs the direction of technological searches and allows to foresee the quality of concentrate and possible results of separation

The development of modern electrometallurgy raises the question of finding new highly refractory materials that increase the service life and productivity of electric furnaces. The study of the melting temperature dependence on the composition of mixtures of highly refractory materials, especially the determination of the areas of formation of solid solutions with high refractoriness, is one of the ways to find highly refractory materials. Among the existing refractories, chromium ironstone, magnesite, zirconium dioxide, etc. deserve great attention. At present there are already a number of studied systems of chromium oxide with oxides MgO, CaO, Аl₂О₃, ZrО₂. The system of Сг₂О3 — SiО₂ has not been studied yet. Its study was carried out by us in connection with the subsequent study of the ternary system Сг₂О₃ — SiО₂— ZrО₂, which is not only theoretical but also of practical interest in the search for new highly refractory materials.

Air supply to the converter is one of the determining characteristics of its operation. The productivity of converters under any conditions is ultimately determined by the amount of air blown in through the tuyere. Meanwhile, the question about the regularities of air blowing in relation to converters of non-ferrous metallurgy in modern literature is poorly covered. Many practical iss.s of converters operation are still unclear. For example, there are completely different opinions on the rational diameter of tuyere, there is no definite opinion on the angle of their inclination, cleaning mode and, most importantly, there is no any justification of the value of the so-called throughput capacity of tuyere, per 1 cm2 of cross-section. This throughput, conditionally recommended by practical data in the range of 0.8-1.0 hm³/cm²·min, is, in fact, the only quantitative characteristic of the converter air regime, taken as a baseline for calculations in the design and operation of converters. Obviously, such throughput capacity of the tuyere is insufficient for characterization of air blowing, as it does not allow to reveal mutual dependence of many blowing parameters, converter operation conditions and other factors.