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Date submitted2023-03-20
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Date accepted2023-09-20
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Date published2023-10-27
Experimental simulation of a system of swamp biogeocenoses to improve the efficiency of quarry water treatment
Mining activities were producing large quantities of wastewater contaminated with nitrogen compounds and metals. With insufficient treatment, these pollutants are released into the environment and have a toxic effect on living organisms. Constructed wetlands are now widely adopted as wastewater treatment systems because of the combination of physical, chemical and biological processes for the removal of contaminants. In this study, an experimental system was modeled to improve the efficiency of the quarry wastewater treatment of a mining enterprise by sharing the higher aquatic vegetation: broad-leaved cattail (Typha latifolia L.), common water-plantain (Alisma plantago-aquatica L.), jointed rush (Juncus articulatus L.) and lower aquatic vegetation (Chlorella sp.). Concentrations of nitrogen compounds and metal were analyzed both in the model and in the treated solution of quarry wastewater for calculation of treatment efficiency. Concentrations of the pollutants in the tissues of the higher aquatic vegetation were analyzed to assess the accumulation capacity and efficiency of translocation of the pollutants. The results of the experimental study showed the practical applicability of the constructed integrated treatment system to reduce the concentration of pollutants in quarry wastewater, as well as increasing the efficiency of treatment by introducing lower aquatic vegetation into the system
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Date submitted2022-10-30
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Date accepted2023-09-20
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Date published2024-02-29
Combined method of phytoremediation and electrical treatment for cleaning contaminated areas of the oil complex
The scale of land pollution with oil waste necessitates the use of economical and effective methods of recultivation. Phytoremediation is one of the simplest methods, but it has a number of limitations, so additional preparation of the territory is often required before it is carried out. Preliminary electrical preparation and subsequent seeding of special phytoremediants are of interest. Passing a constant electric current through the soil volume under a low voltage removes toxicants from deep soil layers even with flooding. In addition, it reduces pollutant content in the upper layer, where the plants root system is located, which creates more favorable conditions for phytoremediants. Adequately selected types of plants will ensure additional soil cleaning, improve its structure and air exchange. The results of two research directions are presented. Experiments on the study of plant resistance to oil-contaminated soil substrate allowed establishing contamination thresholds at which it is advisable to sow a particular species, and to choose optimal phytoremediants. The study of the oil-containing soil cleaning in a monocathodocentric electrochemical installation with the fixation of main characteristics (oil products concentration, soil temperature, volt-ampere characteristics) allows us to develop technical measures to prepare territories for phytoremediation taking into account the relief features.
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Date submitted2022-03-22
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Date accepted2022-11-17
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Date published2023-02-27
Development of composition and study of sorbent properties based on saponite
The development of a comprehensive approach to preventing the pollution of natural objects is necessary due to the high requirements of environmental legislation for the discharge of industrial wastewater. Adsorbents are used in various industries to extract heavy metals from wastewater. In this study the possibility of using saponite clay as a raw material for the production of sorbent for the extraction of copper ions Cu 2+ from industrial wastewater is considered, a recipe and technology of sorbent production are developed, and its chemical composition is established. It has been established that the optimum temperature for heat treatment of the sorbent and corresponds to 550 ºC, since at this temperature saponite extrudates acquire strength (strength 34.1 kg/mm 2 ) and textural properties (specific surface area of pellets 22.803 m 2 /g), allowing them to be used as sorbents. The kinetics of molecular adsorption was studied using model solutions of copper (II) sulfate. The extraction efficiency of copper (II) ions from the model solutions is 93 %. Extraction efficiency of copper (II) ions from copper plating wastewater reaches 94 %. SEM results confirm the presence of metal on the sorbent surface.
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Date submitted2022-10-10
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Date accepted2023-01-19
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Date published2023-12-25
Assessment of the possibility of using leucoxene-quartz concentrate as raw material for production of aluminium and magnesium titanates
Leucoxene-quartz concentrate is a large-tonnage by-product of development of the Timan oil-titanium field (oil-saturated sandstones) which is not commercially used at present. High content of titanium compounds (to 50 % by weight) and lack of industrial, cost-effective, and safe technologies for its processing determine a high relevance of the work. Conventional processing technologies allow increasing the concentration of TiO2, but they are only a preparation for complex and hazardous selective chlorination. The process of pyrometallurgical conversion of leucoxene-quartz concentrate into aluminium and magnesium titanates was investigated. It was ascertained that the temperature of solid-phase reaction in Al2O3-TiO2-SiO2 system necessary for the synthesis of aluminium titanate (Al2TiO5) is 1,558 °С, and for MgO-TiO2-SiO2 system – 1,372 °С. Scaling up the process made it possible to synthesize a significant number of samples of titanate-containing products, the phase composition of which was studied by X-ray phase analysis. Two main phases were identified in the products: 30 % aluminium/magnesium titanate and 40 % silicon dioxide. In products of pyrometallurgical processing in the presence of aluminium, phases of pseudobrookite (3.5 %) and titanite (0.5 %) were also found. It was ascertained that in magnesium-containing system the formation of three magnesium titanates is possible: MgTiO3 – 25, Mg2TiO4 – 35, MgTi2O5 – 40 %. Experiments on sulphuric acid leaching of samples demonstrated a higher degree of titanium compounds extraction during sulphuric acid processing. An integrated conceptual scheme for processing leucoxene-quartz concentrate to produce a wide range of potential products (coagulants, catalysts, materials for ceramic industry) was proposed.
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Date submitted2022-05-12
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Date accepted2022-11-17
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Date published2023-04-25
Microbiological remediation of oil-contaminated soils
- Authors:
- Irina D. Sozina
- Aleksandr S. Danilov
Microbiological remediation is a promising technology for the elimination of environmental contamination by oil and petroleum products, based on the use of the metabolic potential of microorganisms. The issue of environmental contamination by crude oil and its refined products is relevant in the Russian Federation since the oil industry is one of the leading sectors of the country. Mechanical and physico-chemical methods of treatment are widely used to clean oil-contaminated soils. However, the methods belonging to these groups have a number of significant drawbacks, which actualizes the development of new methods (mainly biological), since they are more environmentally friendly, cost-effective, less labor-intensive, and do not require the use of technical capacities. Various bio-based products based on strains and consortia of microorganisms have been developed that have proven effectiveness. They include certain genera of bacteria, microscopic fungi, and microalgae, substances or materials acting as sorbents of biological agents and designed to retain them in the soil and increase the efficiency of bioremediation, as well as some nutrients. Statistical data, the most effective methods, and technologies, as well as cases of using microorganisms to restore oil-contaminated soils in various climatic conditions are presented.
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Date submitted2022-04-15
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Date accepted2022-11-17
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Date published2023-04-25
Uranium in man-made carbonates on the territory of Ufa
The paper presents the results of analyzing uranium content in man-made carbonates (scale crusts) on the territory of Ufa based on examination of 42 samples. The median uranium content in the investigated samples stands at 1.44 mg/kg, which is significantly lower than the background values (scales from the Lake Baikal water, a clarke of sedimentary carbonate rocks) and data on other settlements of the Republic of Bashkortostan. Low values of uranium content are probably associated with the effects of the three leading factors, i.e. specific subsurface geology of the territory (gypsum, limestone); types of water supply; water treatment processes for the centralized type of water supply. Spatial distribution of uranium in man-made carbonates is characterized with uniformity, which is disturbed in two cases, i.e. a change of the water supply type (from centralized to individual); and material of the vessels used for boiling the water. No significant differences were detected when comparing samples of man-made carbonates associated with different sources of water supply (the bucket and infiltration types of water intake) and the types of household filters.
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Date submitted2021-03-31
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Date accepted2022-04-26
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Date published2022-11-03
Features of obtaining metallurgical products in the solid-state hydride synthesis conditions
- Authors:
- Andrey G. Syrkov
- Lyudmila A. Yachmenova
A scientific substantiation of solid-phase feedstock choice and preparation has been carried out, and the thermodynamic and kinetic aspects of solid-state hydride synthesis (SHS) of metal products have been analyzed using the nickel dichloride reduction as an example. The preliminary dehydration modes and methods for controlling the complete removal of crystalline water from chloride raw materials and Olenegorsk superconcentrate, which is natural oxide raw material, are described. Conditions, including initial solid chloride particle sizes, are established under which diffusion complications of reduction to metal in methyldichlorosilane vapor are minimized. Thermodynamic estimates of nickel chlorides and oxides reduction possibility, iron and copper with ammonia and methane at temperatures of 400-1000 K in equilibrium conditions have been carried out. It has been shown that the stoichiometric coefficients of the nickel dichloride in ammonia overall reduction reaction calculated by thermodynamic modeling are in agreement with experimental data. In contrast to the copper dichloride reduction, for nickel dichloride the formation of metal monochloride at the intermediate stage is uncharacteristic, which is associated with a higher thermal stability of nickel dichloride. The main kinetic regularities of the reduction of nickel, copper, and iron to metal under SHS conditions in ammonia, monosilane, and methane, as well as the nickel dichloride with methyldichlorosilane vapor and methane successive reduction, are considered. Approximation of experimental data by topochemical equations in a linear form showed that for reduction degrees a up to 0.7-0.8, these data are satisfactorily described by the Roginsky – Schultz equation. For a > 0,8 the “shrinking sphere” model works better, which confirms the localization of the solid-state reduction reaction at the interface, moves deep into the crystal with the formation of a of interlocked metal germs. The importance and prospects of the results obtained for the theory development of metallurgical processes, deep complex processing of natural iron oxide raw materials, metal products and new generation materials production, including superhydrophobic ones, are discussed. The relevance of the study from the point of view of applying the method of physical and chemical analysis to the study of complex heterogeneous metallurgical processes is noted.
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Date submitted2019-06-27
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Date accepted2019-09-07
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Date published2019-12-24
Optimization of geometrical parameters of the hydro-cyclone inertial Venturi separator
- Authors:
- V. N. Makarov
- A. V. Ugolnikov
- N. V. Makarov
The usage of nanosized particles as modifying agents opens new possibilities in the creation of materials with unique properties. The effective qualitative improvement of Russia's GDP structure is based on the recycling of technogenic mineral formations (TMF) and the production of high-tech products. Numerous studies have shown that the efficiency of this process is limited by high requirements to the fractional composition, median size, and dispersion of TMF particles, as well as imperfection of equipment and technology and their classification. The strict classification requirements must be taken into account, when developing separation methods for the dispersion of the median sizes of TMF microparticles under the conditions of the probabilistic distribution of the physical and mechanical parameters of the feed. The studies covered in the article are based on the provision on a significantly greater influence of inertial forces on the trajectory of a hydrodynamically unsteady motion of the dispersed «a microparticle – a drop of liquid» system during the hydro-cyclone separation with respect to the aerodynamic forces of their movement in a fluidized bed. The paper shows that within the range of kinetic energy of the translational motion of liquid droplets, which overcomes the aerodynamic barrier of coagulation of hydrophobic TMF particles, the minimum diameter of absorbed microparticles during hydro-cyclone coagulation depends only on the magnitude of the angular velocity of rotation of the liquid droplets. We obtained the equations for the Euler and Reynolds criteria, their average values, and the relaxation time of liquid droplets with integrated micro and nanoparticles of TMF, depending on their median size during hydro-cyclone separation. The developed mathematical model of inertial hydro-cyclone separation of finely dispersed TMF allows determining the optimal geometric parameters and energy characteristics of the Venturi separator, its aerator, and the position of the receiving tanks. The experimental results confirmed the possibility of classifying finely dispersed wastes of mining and metallurgical production in the range of median sizes (0.5-5)∙10 –6 m by fractions with a dispersion of not more than 20 %.
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Date submitted2019-07-11
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Date accepted2019-09-04
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Date published2019-12-24
Recent scientific research on electrothermal metallurgical processes
- Authors:
- E. Baake
- V. A. Shpenst
A wide range of industrial metallurgical heating and melting processes are carried out using electrothermal technologies. The application of electrothermal processes offers many advantages from technological, ecological and economical point of view. Although the technology level of the electro heating and melting installations and processes used in the industry today is very high, there are still potentials for improvement and optimization due to the increasing complexity of the applications and the strong requirements regarding the performance and quality of the products but also regarding the reduction of time and costs for the development of new processes and technologies. In this paper recent applications and future development trends for efficient heating and melting by electrothermal technologies in metallurgical processes are described along selected examples like induction heating for forging or rolling of billets, heat treatment of strips and plates, press-hardening processes, induction surface hardening of complex geometries, induction welding as well as induction melting processes.
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Date submitted2019-05-02
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Date accepted2019-07-09
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Date published2019-10-23
Effect of Temperature on Solid-state Hydride Metal Synthesis According to Thermodynamic Modeling
Thermodynamic modeling of the reduction of copper dichloride in the media of various gaseous hydrides (ammonia, monosilane, methane) in the temperature range 273-1000 K was carried out. Calculations show that in narrower temperature ranges corresponding to the reactions of solid-state hydride synthesis (SHS) of metal sub- stances metal formation is usually supported by theoretical propositions. As a result of thermodynamic modeling, a principal result was obtained on the suppression of competing processes of nitriding, siliconizing and carbonization of metal under SHS conditions, which is important for metallurgical production. This additionally substantiates the correctness of previous experimental studies of SHS metals with modified surface and improved properties. By mod- eling, it was found that the reduction of solid copper dichloride to metal in ammonia or methane occurs stepwise (se- quentially, according to the Baykov rule) through the intermediate stages of the formation of a compound of low- valent copper – copper (I)chloride.
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Date submitted2018-10-31
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Date accepted2018-12-30
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Date published2019-04-23
Produc-tion of Silver Ruble and participation of the Saint-Petersburg Mining university in the development of monetary industry of Russia
The article is a continuation of the research on the production of silver rubles and the development of Russian coinage. Graduates of the Saint-Petersburg Mining University contributed to the reputation and history of the Saint-Petersburg Mint as an advanced and high-tech production. The article describes the beginning of the development of silver ruble production, the use of ores from the Nerchinskoye deposit in the Transbaikalia to produce the main raw material in the form of concentrates and a silver alloy. The materials for the study used unique exhibits of the Mining Museum of the Saint-Petersburg Mining University, which are associated with the history of coinage and the Saint-Petersburg Mint. Some samples of lead-silver ores cast billets, and stamped coins were studied to determine the technological features of their manufacture. An analytical study of the features of minting and obtaining the first Russian silver coins according to some data of the royal decrees was carried out. The current level of technology and knowledge, as well as the special equipment of the laboratories of the Saint-Petersburg Mining University, made it possible to re-evaluate the characteristic features of the production of silver coins.
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Date submitted2018-05-14
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Date accepted2018-07-15
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Date published2018-10-24
Experience of Integrated use of gold-bearing raw material in the production of precious metals
- Authors:
- V. V. Zhmurova
- N. V. Nemchinova
With the depletion of rich gold-bearing ores, the processing started to use polymetallic ores, which, in addition to precious metals, contain other elements that could be valuable after recovery. The problem of using such ores is extremely difficult because of the high cost of recovery of associated valuable components. The paper presents the results of studies on the integrated use of extracted gold-bearing raw materials based on the example of the Berezitovoye deposit (Amurskaya oblast), they have low content of precious metals and many heavy non-ferrous metals (copper, lead). Experimental work was carried out to obtain copper by the method of cementation from solutions formed after the leaching of the impurities of gold-containing cathode deposits with hydrochloric acid. The cementing metal was iron turnings (waste products of the turning shop of the enterprise). Next, it was proposed to use cemented copper as a collector during re-melting of slags – wastes of processing of low-grade polymetallic ores containing precious metals. The authors obtained ingots of alloyed gold with gold weight fraction of 16 %, which meets the requirements of TU 117-2-7-75 on the content of non-ferrous metals. During hydrochloric acid treatment of cathodic deposits silver partially passed into the solution, it was recovered together with cemented copper and, in subsequent melting, passed into alloyed gold. Thus, the method proposed by the authors helps to reduce the content of precious metals in the «incomplete production cycle» of the gold recovery factory. The opportunity of selling the cementation copper at the enterprises specializing on manufacturing of jewels is shown; the expected economic effect at the same time amounted to more than 1.8 million rubles.
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Date submitted2017-11-12
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Date accepted2018-01-23
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Date published2018-04-24
Metallurgists of the Mining university and development of monetary industry. 245 years of history
Monetary industry combines several stages of metallurgical processes, which are continuously improved with the development of technology and the level of knowledge in the field of non-ferrous metals. The graduates of the Mining Institute, metallurgists of several generations, took part in establishment the Mint and development of technology to produce coins. Since January 24, 1718, when Peter the Great signed the decree «on production of small and large coins ...», the history of the monetary system of Russia and the coining of the first silver rubles began, which subsequently formed the basis of money relations. Twenty-four graduates of the mining and metallurgical departments of the Mining University worked as heads and münzmeister of the Mint. Silver rubles and work of Russian münzmeisters provided financial stability in Tsarist Russia from 1718 to 1917 and laid the foundation for further development of the monetary industry, taking into account new knowledge in the field of enrichment, preparation of polymetallic ores and their melting, and also stamping and processing of precious metals. This is the history of Russia and St. Petersburg, it combined the history of the Mining University, which this year will be 245 years old. It is of scientific interest to restore historical justice and update the methodological knowledge in the field of technology of monetary industry and metallurgical processes.
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Date submitted2015-07-20
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Date accepted2015-09-26
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Date published2016-02-24
Prospects of biotechnologies application in metallurgy and enrichment
- Authors:
- N. M. Telyakov
- A. A. Darin
- V. A. Luganov
In recent years, application of biotechnologies in enrichment processes and processing of metal-containing ores has gained broad development, considering essential advantages of these technologies from the point of view of economic efficiency and ecological safety. Processes with the application the hemolitotrofnykh of acidophile microorganisms of Acidithiobacillus ferrooxidans, At. thiooxidans, Leptospirillum ferrooxidans and others, are of great interest. This article is devoted to the problem of biocultures application for efficiency improvement of the ore pretreatment technology and extraction of valuable components from metal-containing crude ore. The analysis of the biotechnologies and microorganisms applied at domestic and foreign enterprises is given, alongside with the theoretical bases of ore bioprocessing, research results of oxide and sulphidic metal-containing ores processing technology development, with the application of microorganisms and research results of the mechanism of destructive impact of a certain type bacteria on siliceous ores.
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Date submitted2009-09-23
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Date accepted2009-11-23
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Date published2010-06-25
Experience of mediatext in social culture teaching creating
- Authors:
- I. V. Trofimova
This article is devoted a problem of creation of the mediatext as new format for presentation of the scientific information. On a material of culture of the 1930 which have marked transition from avant-garde to totalitarianism, the (video) picture reflecting leading tendencies of an epoch and the form of their artistic realisation is built.
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Date submitted2009-09-03
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Date accepted2009-11-05
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Date published2010-06-25
Multimedia presentations as an element of lecturer work in technical higher school
- Authors:
- N. A. Egorenkova
This article is devoted to methodological aspects of modern computer technologies introduction to liberal arts teaching in technical higher school. Question of reasonability of lectures accompaniment by multimedia presentation is depicted. The experience of Russian Language and Culture of Speech lectures multimedia presentation creation is described in the article, recommendations to blocks of presentation preparation are given, some methods of working with Microsoft PowerPoint program with the help of which studying process could be done more effective, multisided, attractive, dynamic, possible to stimulate students’ creative activity are described.
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Date submitted2009-08-07
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Date accepted2009-10-14
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Date published2010-02-01
Calculation of material streams of the pirometallurgical cycle of processing of copper sulphidic raw materials
- Authors:
- N. V. Danilova
The technology pirometallurgical a cycle of processing of copper sulphidic materials is considered. The technology includes autogenous fusion in furnaces Vanjukova, converting copper steins and copper refinement. The primary goals of drawing up of model and the accepted assumptions are described. The equations of system of model are balance expressions for each of material streams. Expressions for calculation of material streams pirometallurgical a cycle of processing of copper sulphidic raw materials are found.