Metallurgical Raw Materials Research Articles

ДОСЛІДЖЕННЯ ТЕХНОЛОГІЧНИХ ПОКАЗНИКІВ РОБОТИ ВІБРАЦІЙНОГО ГРОХОТА З ЕЛАСТИЧНИМИ СИТАМИ

In the metallurgical branch of industry, the problems of separation according to the given size - screening of the original metallurgical raw materials, in particular coke, are relevant. This ensures high-quality operation of the technological equipment of blast furnaces and supply of blast furnace coke of regulated size. In this regard, research is constantly being conducted and the development of new methods of screening and modernization of devices to improve the performance of vibrating screens continues. The purpose of the scientific work: an experimental study of the technological parameters of the vibration screen with elastic sieves. The paper gives a description of the laboratory vibrating sieve with an elastic sieve, which is used in the research. An experimental study of the technological parameters of the screening process of the vibrating screen was carried out and the dependence of the technological indicators on the parameters of the vibrating screen was constructed. It has been shown that the highest screening efficiency is observed at oscillation frequencies in the range of 22-27 Hz. At these frequencies, the efficiency indicators of the screening process vary between 78-90%. A change in the value of the specific load from 10 t/(h m^2) to 16 t/(h m^2) causes a gradual decrease in the screening efficiency from 90% to 65%.

Studying the Compressibility of Ground Metallurgical Raw Materials

Studying the Compressibility of Ground Metallurgical Raw Materials

ПРОМИСЛОВІ ТИПИ РОДОВИЩ КАРБОНАТНОЇ СИРОВИНИ ТА ЇХНІ ПАРАМЕТРИ КОНДИЦІЙ ДЛЯ ПІДРАХУНКУ ЗАПАСІВ

The article systematizes the main industrial types of carbonate rock deposits in Ukraine and analyzes the main directions of their use. Metallurgical production and the sugar industry are identified as the main areas of use that are in short supply. Most of these explored reserves of carbonate rocks are located within the Donetsk region and the territory of Crimea. The number of explored reserves in the rest of the territory does not provide a sufficient period of operation and work of industrial enterprises for more than 10-15 years. The most effective way to provide reserves is to review the objects that are being developed today in other areas of use (except metallurgical raw materials and the sugar industry) to allocate a part of the reserves that may be suitable for these scarce areas. The analysis and systematization of the cut-off parameters for the reserves calculation of various types of carbonate rocks in accordance with their industrial types and the requirements of geological and economic evaluation were carried out. The basic parameters for the calculation of reserves are the quality indexes, which are put forward by the direction of use in the standards, the depth of the reserves calculation, the minimum thickness of the mineral from 2 m, the limitation of contours within the license area and the mining right-of-way, in the contour of the quarry at the end of the development. Parameters that take into account the risks of unconfirmed reserves associated with karst areas, high clayey rocks are almost not used, although they can be an important tool especially for operational conditions.

Bonding Mechanism and Process Characteristics of Special Polymers Applied in Pelletizing Binders

Pellet ore not only has excellent metallurgical and mechanical properties, but is also an important metallurgical raw material used to solve the problem of increasing depletion of global high-grade iron ore resources. Bentonite has long been widely used in pellet ore production, which is not only expensive but also causes serious metallurgical pollution. Organic binders can form stronger adhesion and cohesion with mineral particles inside the green pellets than capillary forces, which greatly improves the pelletizing rate and significantly increases the strength of green and dry pellets, and it becomes an indispensable alternative to bentonite because it volatilizes pyrolytically at high temperatures, leaving almost no inorganic contaminants inside the pellet ore. In order to let more pellet researchers fully understand the research status and pelletizing theory of organic binders, this review systematically summarizes seven common organic binders, and elaborates on their adhesion mechanism and process characteristics, so as to provide references for pellet researchers and readers to further prepare cost-effective pellet binders and improve advanced pelletizing technology.

Methods, dynamics and structure of coal production in Russian deposits: problems and solutions

Introduction. The structure of coal mining in Russian deposits is heterogeneous due to significant imbalances dictated by different geological and engineering conditions of mining in different regions of the country. Due to the consequences of the COVID-19 pandemic and the crisis associated with it, the dynamics of coal production is not stable, and in recent years there has been a decline in economic growth in companies in the coal sector of the Russian economy. Today it is important to focus on the development of new deposits, the search for safer and more reliable ways of mining. This will make it possible to optimize coal mining management mechanisms and provide solutions to the problems of increasing economic efficiency in the coal sector of the Russian Federation. Research objective is to scientifically substantiate the reasons and conditions for the formation of long-term demand for resource potential for the extraction of energy and coking coal using situational analysis. Methods of research. In order to study the problems of the coal sector development, a scenario analysis of the dynamics and structure of coal mining in Russian deposits was carried out. As a result, hypotheses about the need for complex extraction of energy and coking coal grades were confirmed. It has been scientifically proven that the introduction of open-underground geotechnology in Russian deposits serves as a way to rationalize mining operations, and increases the final effect of coal mining. Results. The characteristics of the main types of coal reserves in Russian deposits are presented. Of practical importance is the study of the dynamics of A-Property coal production in 2020–2021 in various companies. Conclusions. As a result of the conducted research, the article draws an important conclusion about the need to expand the practice of obtaining and using anthracite, despite its high level of rarity of extraction. The organization of new methods of anthracite extraction and use in the industry will improve the production of metallurgical raw materials.

Technogenic Metallurgical Raw Materials for Producing Ceramic Materials with Anorthite

Technogenic Metallurgical Raw Materials for Producing Ceramic Materials with Anorthite

Preparation of hot-pressed coal briquette with the extract from direct coal liquefaction residue

Direct coal liquefaction residue (DCLR) is an industrial by-product from the direct coal liquefaction process. It is harmful to the environment and the human body when directly charged or used due to the high content of sulfur, ash, and polycyclic aromatic hydrocarbons (PAHs). Therefore, it is of great importance to treat and utilize DCLR. In this paper, the thermal extraction method was applied to extract DCLR with N-methylpyrrolidone (NMP), and the hot-pressed coal briquette (HPCB) was prepared with DCLR extract and anthracite powder. DCLR and its extract and residue were characterized by TG, FTIR, and GC-MS. The ash content was decreased from 11.72% to 0.72% and the sulfur content was decreased from 1.72% to 0.09% after thermal extraction. TG analysis shows that the weight loss of the extract was about 30.4% higher than that of the residue during the pyrolysis process, indicating that the extract contained more light components. FTIR analysis shows that the thermal extraction process had strong extraction capacity for aliphatic hydrocarbons and aromatic hydrocarbons, but weak extraction capacity for carboxyl, phenol, or alcohol groups. GCMS shows that 60.6% of the volatile substances in the extract were PAHs, while the residue had only 6.8% of PAHS. It is proven that the residue has been rendered harmless to humans and the environment. Moreover, the HPCB with a compressive strength exceeding 2.5 MPa was prepared by using the DCLR extract as a binder and anthracite powder as a raw material. It has the potential and advantages of being used as a metallurgical raw material.

Prospects of Daschkesan iron ore deposit development

The topicality the subject. To meet Azerbaijan's growing demand for ferrous metallurgical raw materials, there are sufficient reserves of iron ore deposits that can be put into industrial operation. These are related to the future development of the mining industry in the Daschkesan iron ore group, including the promising South-Daschkesan and Damirov fields. The re-exploitation of the Daschkesan iron ore group will have a positive impact on the socioeconomic development of the region, as well as strengthen the position of the mining industry and metallurgy in the country's non-oil sector. The resumption of Daschkesan iron ore production will also make an important contribution to the development of a number of by-products, improve employment in the regions, and create new and wider opportunities for local companies. The purpose of the study. In the rich areas of the Daschkesan iron ore deposit, due to the reduction of the amount of iron in the ores, the enrichment is the production of granules for the production of iron by the sponge method. Research methods. Along with the study, research and exploration of ferrous metal ore deposits in the territory of the republic, geophysical research and geological exploration work has been started for the re-commissioning of the Daschkesan iron ore deposit. The first 3-dimensional geological model of the Daschkesan iron ore deposit was developed using special software. The goal is to produce iron ore deposits in a short period of time and meet the demand for quality raw materials for the production of ferrous metallurgy products. Results. Considering that the use of wastes will increase the efficiency of field development, it is necessary to economically evaluate, sort and use metal-bearing wastes discharged into the Goshgarchay River during the enrichment of magnetite ore in the past as a valuable building material such as sand and gravel in Ganja region. It is planned to establish joint ventures with waste from mining enterprises and concentrators, slag from the pipe rolling plant, and waste from the Ganja aluminum plant. Conclusion. The future development of the mining industry in our country can be achieved through the complex use of iron ore deposits of the Daschkesan group, quarry waste, waste from the enrichment of magnetic ores.

Вдосконалення технології виробництва та покращання якісних характеристик комплексного флюса

The article considers the possibility of increasing the efficiency of the modern agglomeration process, which is carried out by improving the technology of complex flux production. The domestic and world experience of development and use in the processes of smelting of metallurgical raw materials of a new type - complex flux - is summarized. It is noted that this type of flux adds a significant set of mineralogical compounds to the sintering charge, which significantly improve the sintering conditions and the quality of the sintering raw materials. A method of producing a complex flux by combining the processes of calcining limestone and the formation of calcium ferrites is proposed. The possibilities and advantages of using specialized software for the analysis of limestone dissociation reactions under different conditions are shown. One of the directions for the production of a complex flux of a given composition and properties is highlighted, the basis of which is the production of combined granules formed by pieces of limestone with a coarseness and a shell of iron ore materials (concentrate, iron ore), by combining the processes of calcination of limestone and the formation of calcium ferrites. Thermodynamic analysis shows the high reliability of the interaction of lime with oxides of ore material with the formation of a complex flux of the given composition and properties. The process is implemented by sintering on a conveyor machine using agglomeration technology. The main parameters of the technological mode of complex flux production have been developed. It has been proven that in the development and improvement of the technology for the production of complex flux from limestone granules with rolling of iron-containing material, the correct choice of limestone size, fuel, as well as the values of other technological parameters is of great importance. The results of the conducted research confirm the technological feasibility of the chosen direction of complex flux production due to the combination of lime and ferrite heat production processes.

МИРОХОЗЯЙСТВЕННЫЕ СВЯЗИ В ГОРНО-МЕТАЛЛУРГИЧЕСКОМ КОМПЛЕКСЕ: СТРАНЫ АЗИИ, СЕВЕРНОЙ АФРИКИ И УКРАИНА

The article analyzes the situation on the world market of mining resources. The impact of demand for metallurgical raw materials from Asian countries has been assessed. It is shown that Asian countries in the conditions of rapid urbanization and the development of infrastructure facilities will show an increasing demand for resources for the metallurgical industry. The influence of the mining and metallurgical complex of Ukraine on the world market of iron ore and ferrous metals is investigated. Ukraine's largest exports were ferrous metals and iron ore, which accounted for 28% of all export revenue over the past three years. The main countries buying iron ore were China and the EU countries. Iron and steel went to Turkey, China, Saudi Arabia, Egypt, and EU countries. The current situation in the mining and metallurgical industry of Ukraine will affect world economic relations in general. There may be a shortage of iron ore and ferrous metals on the world market, Turkey, Egypt, Viet Nam may be in the most vulnerable position.

A Resource-Saving Process for Obtaining Sulfoferrite Clinkers and the Properties of Cements Made with Them Involving the Use of Metallurgical Waste

Processing of metallurgical raw materials — especially those with high concentrations of sulphur — is associated with huge amounts of waste, which can be used as the principal component in the production of materials for various industries. This paper describes the results of development work that dealt with high-reactivity raw mixes and the resource-saving production of cryoannealed sulfoferrite clinkers when natural and mining, metallurgical and chemical wastes are comprehensively used as components. The properties of cements made with the above waste components were also studied. It was found that high-grade cements can be obtained due to the hydraulic activity of cement mixes obtained from clinkers that were produced by annealing of optimum-composition three-component raw mixes containing limestone, phosphogypsum and hematite. The conducted study confirms that metallurgical waste can serve as an efficient material for the production of high-strength materials made with sulfoalumoferrite cements. The optimum parameters for the production of sulfoalumoferrite clinkers and cements made on their basis were found to be as follows: КН = 0.667, nS = 1.5–2.0 and the annealing temperature of 1,150–1,200 оС. The hydraulic activity of sulfoalumoferrite cements obtained from clinkers that were produced by annealing of optimum-composition three-component raw mixes containing limestone, phosphogypsum and hematite ensures that such cements are of M400 and M500 grades. The samples have a rather high strength, as well as high sulphate and wear resistance.

A mathematical model of metallization of titanium-magnetite ores of Kachkanar deposit in Midrex shaft furnace

Development of a technology for obtaining direct reduction iron from titanium-magnetite ores, which will be the main ore base of the Ural ferrous metallurgy in the future, is one of the urgent tasks of metallurgical science. The world and domestic experience of the development of direct iron reduction processes, which are the most environmentally friendly of all existing methods of obtaining iron from ore considered. It was shown that the technology of metallization of iron ore materials in the Midrex shaft furnace has received the most widespread application. It is noted that the accumulated experience of using Midrex technology in Russian Federation will allow increasing the production of metallurgical raw materials with a reduced carbon footprint. An algorithm and a block diagram for calculating technical and economic indicators of the metallization process for the Midrex process shaft furnace are described. A methodology for calculating material and thermal balance of the Midrex process has been developed, taking into account the use of iron ore raw materials containing vanadium and titanium in the charge. On its basis, an algorithm was developed and a mathematical model of the metallization process was implemented, calculations of the metallization process of titanium-magnetite pellets obtained from the ores of the Kachkanar deposit in the Midrex mine furnace were performed. A comparison of the indicators of the metallization process of titanomagnetite pellets carried out in the shaft furnace of JSC “OEMK named after A.A. Ugarov” and obtained using the created software product showed satisfactory convergence of the results.

Transformation of grains of technological raw materials in the process of obtaining fine powders

Crushing and grinding of materials are the most common processes of sample preparation for subsequent analysis and industrial application. Recently, grinding has become one of the most popular methods for producing nano-sized powders. This study investigates certain features of grain transformation in the process of grinding ores with finely dispersed valuable components in order to liberate them, as well as specifics of grinding metallurgical raw materials, metals and their mixtures for using them as initial components in metallurgical and other technological processes. We identified and examined structural and morphological changes of various powders after ultrafine grinding using the methods of scanning electron microscopy and X-ray microanalysis. It was proved that in order to take into account sample preparation artifacts during analytic studies of solid samples and development of technological processes, fine grinding of heterogeneous materials, especially if they contain metals, requires monitoring of the ground product by methods of scanning electron microscopy and X-ray microanalysis.

Leaching of Ca-Rich Slags Produced from Reductive Smelting of Bauxite Residue with Na2CO3 Solutions for Alumina Extraction: Lab and Pilot Scale Experiments

Sustainable utilization of Bauxite Residue (BR) is currently one of the greatest challenges being tackled by the alumina industry, due to its high production rates and limited reuse options. The present work is concerned with the use of BR as a candidate metallurgical raw material for iron (Fe) production and aluminum (Al) extraction. In more detail, at first, BR undergoes reductive smelting to extract its Fe content and produce a slag of mainly calcium aluminate composition. In a second step, Al contained in the calcium aluminate phases is extracted hydrometallurgically by leaching with a Na2CO3 aqueous solution. The focus of the current study is the optimization of this leaching process, and it was performed in two stages. The first was a laboratory scale investigation on the main parameters affecting the extraction rate of Al. The second stage was performed in pilot scale and incorporated observations and suggestions based on the laboratory scale investigation. Laboratory work showed that more than 50% of aluminum could be easily extracted in less than 1 h, in 5% S/L, at 70 °C and with an 20% excess of Na2CO3. Pilot scale work, by successfully applying the suggestions derived from laboratory scale work, achieved an average Al extraction of 68% from a 10% S/L pulp, with a slag of optimized composition in relation to the one used in the laboratory scale.

Mineralogical justification for potentiality of producing marketable hematite products


 
 
 Hematite quartzites are a product of weathering of magnetite quartzites, which make up the ferruginous horizons of deposits of the Precambrian banded-iron formation. They occur all over the planet. The largest deposits are found in the iron-producing areas and basins of Central Kazakhstan, the Kursk magnetic anomaly, the Karelian-Kola region, Western Australia, Southeastern India, Brazil, the United States, and Canada. The geological and mineralogical issues of hematite quartzites as raw materials for producing concentrate and sinter ore have been studied most deeply and comprehensively for the deposits of the Kryvyi Rih basin and Central Kazakhstan. However, when developing an effective scheme for producing high-quality metallurgical raw materials, the mineralogical features of hematite ores have been taken into account insufficiently. The aim of the authors of the present work was to study the localization, structure of deposits and mineral composition of hematite quartzites as raw materials for sinter ore and concentrate production. Data from geological observations and mineralogical studies were used as source material. Proven geological, mineralogical, petrochemical methods were used. In accordance with the obtained results, the hematite quartzites are composed of ore-forming (quartz, hematite) and secondary (relict and newly formed) minerals. The total content of the hematite and quartz exceeds 90 mass %. The peculiarity of Ushkatyn III deposit ores is the high content of manganese oxides. The depth of distribution of the weathering crust composed of hematite quartzites varies from 200 to 1000 m. The hematite quartzites’ bodies are characterized by a zonal structure. Their central parts are represented by martite-micaceous hematite, micaceous hematite- martite quartzites; intermediate ones by martite quartzites; peripheral parts – by dispersed hematite-martite, kaolinite-martite-dispersed hematite quartzites. The horizons differ in the quantitative ratio of these varieties. The quantitative ratio of mineral varieties of hematite quartzites, morphology of individuals and aggregates of ore-forming and secondary minerals, their chemical composition and physical properties must be taken into account when developing the optimal technology for the production of high-quality hematite concentrate.
 
 

Research Status of Microwave-assisted Reduction Technology of Pyrolusite

Manganese ore is an important metallurgical raw material that holds an important strategic position in the national economy of China. However, the grade of manganese ore in the country is mostly low, and the utilization efficiency of low-grade manganese ore resources is low, which seriously restricts the healthy and stable development of China’s metallurgical industry. As a new green heating method, microwave is expected to address the problems of conventional methods and realize the effective utilization of low-grade manganese ore. In this paper, the research status of the microwave composite reduction of pyrolusite in recent years is reviewed. Microwave plays an important role in metallurgy, and it is the current direction pursued to improve the research level of microwave heating and extend it to actual industrial processes.

Magneto-inductive systems as a method to reduce the environmental risks of the existing systems of incoming quality control of metallurgical raw materials

The advantages of automated systems for magnetic inductive incoming quality control of raw materials of large metallurgical enterprises are demonstrated. Environmental risks under the existing visual control system were assessed.

On the Possibility of Electrochemical Processing of Dump Industrial Iron-Antimony Matte

One of the most important and urgent problems facing the metallurgical industry is the problem of processing dump mattes (DM). These are alloys of sulfides of various metals, and in some locations have accumulated to such an extent that they fill entire landfills with environmentally hazardous substances. During prolonged storage in air, DM decomposes and produces toxic substances. Therefore it is important to find an environmentally safe way to store or processes DM. The available information on the technologies for processing sulfide-oxide metallurgical raw materials and sources of DM formation are analysed in this study. Chemical analysis of the DM indicates a high iron content, which a priori determines the high conductivity of dump materials. The aim of this research is to examibne the physicochemical properties of the DM melts of the Kadamjai antimony industrial complex, in which, according to the technological schedule, iron and antimony are accumulated in sulfide form, followed by pyroelectrochemical processing of them into commodity products in the case of optimal metal current yields and good extraction. The electrical conductivity (æ) of the industrial DM melt is characteristic of multifunctional conductors with a predominant semiconductor mechanism of conductivity. The addition of a heteropolar additive (Na2S) into the DM melt suppresses the electronic component of conductivity and decreaseds æ in the system to values that are typical for ionic melts. Current-voltage characteristics for the composition of the system with 60 and 70 mol. % Na2S indicate polarization in the melts. The electrolysis of DM-Na2S melts is accompanied by the release of sulfur on the anode. For a final assessment of the possibility of using electrochemical processing of DM melts into antimony metal, it is recommended that a preliminary economic calculation of the entire technological process be performed.
 Keywords: dump mattes, iron and antimony sulfides, physicochemical properties, ecology, utilization

NH3 sensing performance of Pt-doped WO3·0.33H2O microshuttles induced from scheelite leaching solution

WO3·0.33H2O microshuttles (WMSs) self-assembled by numerous nanorods along the same direction were prepared based on a cheap tungsten-containing metallurgical raw material by combination processes of NaOH leaching and one-step hydrothermal method. The microstructures and gas sensing properties of various concentrations (0, 0.7, 1.0, and 1.3 mol%) of Pt-doped WMSs were investigated to improve their performance. The microstructural characterizations demonstrated that the WMSs assembled by one-dimensional WO3·0.33H2O nanorods were approximately 0.8–1.9 μm in diameter. Such nanorods exhibited a single hexagonal structure with their diameters ranging from 17 to 62 nm. The gas sensing properties indicated that Pt-doped WMSs showed superior gas sensing performance in terms of the sensor response and NH3 selectivity in the operating temperature range of 25−225 °C as compared with pure one, and simultaneously Pt doping could significantly reduce the detection limit of NH3. Especially, 1.0 mol% Pt-doped WMSs exhibited the highest response of 28.2–1000 ppm NH3 at 175 °C, which was 4 times higher than pure one at 50 °C, indicating that it is a potential candidate material for the detection of NH3 gas.

О кинетике извлечения примесей из железного концентрата, полученного в ходе гидрометаллургической переработки чернового медного концентрата

The purpose of the paper is to study the physical and chemical features of high-quality iron concentrate precipitation from nitric acid leaching solutions of low-grade copper-sulfide raw materials, and to obtain a highly profitable product which is suitable for direct processing at ferrous metallurgy enterprises. To conduct the experiments on obtaining impurity rich and depleted iron concentrate a hydrolytic precipitate containing 54.6% iron and numerous impurities obtained as a result of processing of nitric acid leaching solutions of rough copper sulfide concentrate from the Zhezkazgan deposit is used. Analytical studies of initial materials and resulting products of the processes under investigation are conducted using the modern certified methods including the x-ray spectral, x-ray phase, atomic absorption analysis, mass spectrometry method with inductively coupled plasma. We have obtained a high-quality iron concentrate containing minimal amounts of silicon, aluminum, phosphorus and sulfur as well as partial and generalized equations that give an idea of the influence of the studied factors on the indicators of the iron concentrate production process. The apparent activation energy of the process has been calculated - 46.77 kJ/mol. It probably indicates the presence of diffusion complications caused by the formation of solid products passivating the surface of the material being dissolved. The principal possibility of obtaining high-quality iron concentrate from processing poor copper-sulfide concentrate middlings of the Zhezkazgan deposit is shown. The mathematical processing of experimental data has resulted in the determination of equations that characterize the degree of influence of the studied factors on the process indicators. It is found out that the production process of the saleable iron concentrate proceeds in the mode of diffusion restrictions. It is the first time, when multivariate generalized dependencies are obtained for the process under consideration and their analytical transformations are performed. These methods can be used to study the analogous processing of similar metallurgical raw materials.