Papers by Dmitriy Zinoveev
Vanadium containing slurry is a by-product of vanadium pentoxide by hydrometallurgical methods fr... more Vanadium containing slurry is a by-product of vanadium pentoxide by hydrometallurgical methods from vanadium slag. It is promising technogenic raw material for vanadium production. The phase analysis of vanadium-containing slurry by X-ray diffraction method has shown that it contains vanadium in spinel form (FeO∙V2O3). The various oxidation roasting methods for slurry treatment have been studied for increasing vanadium extraction into the solution. It has shown that the most effective additive is 1% CaCO3 at a roasting temperature of 1000 °C. The oxidation roasting of vanadium-containing slurry with the additive led to increase acid-soluble form of V2O5 from 1.5 to 3.7% and decrease the content of FeO∙V2O3 from 3 to 0.4%. These results have confirmed the efficiency of the application of oxidation roasting to convert vanadium compounds into acid-soluble forms. The conversion mechanism of spinel to acid-soluble phases during oxidation roasting with additives was investigated by thermo...
Metals, 2019
The chemical and mineral composition of the red mud from the Ural Aluminum Plant were studied by ... more The chemical and mineral composition of the red mud from the Ural Aluminum Plant were studied by XRF, XRD, and Mössbauer spectroscopy. Experiments on reductive smelting of red mud were carried out in a range of temperatures (1650–1750 °C) to recover iron from the aluminum production waste with maximum efficiency. It was found that it is possible to obtain pig iron with a high content of titanium, phosphorus, and vanadium, and low sulfur content. The efficiency of iron recovery at 1750 °C was found to be around 98%. Thermodynamic calculations were carried out to assist in finding the optimal conditions for the process (e.g., carbon content, furnace temperature, slag liquidus temperature). It was also found that the pig iron phase obtained at 1650 to 1700 °C is not separated from the slag phase into ingot compared with the sample obtained at 1750 °C. Pig iron obtained at 1750 °C can be used to produce molds for the steel-casting equipment.
Sustainability
Managing red mud (RM), a solid waste byproduct of the alumina recovery process, is a serious ecol... more Managing red mud (RM), a solid waste byproduct of the alumina recovery process, is a serious ecological and environmental issue. With ~150 million tons/year of RM being generated globally, nearly 4.6 billion tons of RM are presently stored in vast waste reserves. RM can be a valuable resource of metals, minor elements, and rare earth elements. The suitability of RM as a low-grade iron resource was assessed in this study. The utilization of RM as a material resource in several commercial, industrial operations was briefly reviewed. Key features of iron recovery techniques, such as magnetic separation, carbothermal reduction, smelting reduction, acid leaching, and hydrothermal techniques were presented. RMs from different parts of the globe including India, China, Greece, Italy, France, and Russia were examined for their iron recovery potential. Data on RM composition, iron recovery, techniques, and yields was presented. The composition range of RMs examined were: Fe2O3: 28.3–63.2 wt....
Sustainability, 2022
Managing red mud (RM), a solid waste byproduct of the alumina recovery process, is a serious ecol... more Managing red mud (RM), a solid waste byproduct of the alumina recovery process, is a serious ecological and environmental issue. With ~150 million tons/year of RM being generated globally, nearly 4.6 billion tons of RM are presently stored in vast waste reserves. RM can be a valuable resource of metals, minor elements, and rare earth elements. The suitability of RM as a low-grade iron resource was assessed in this study. The utilization of RM as a material resource in several commercial, industrial operations was briefly reviewed. Key features of iron recovery techniques, such as magnetic separation, carbothermal reduction, smelting reduction, acid leaching, and hydrothermal techniques were presented. RMs from different parts of the globe including India, China, Greece, Italy, France, and Russia were examined for their iron recovery potential. Data on RM composition, iron recovery, techniques, and yields was presented. The composition range of RMs examined were: Fe2O3: 28.3–63.2 wt....
Metals, 2020
Red mud is an iron-containing waste of alumina production with high alkalinity. A promising appro... more Red mud is an iron-containing waste of alumina production with high alkalinity. A promising approach for its recycling is solid-phase carbothermic roasting in the presence of special additives followed by magnetic separation. The crucial factor of the separation of the obtained iron metallic particles from gangue is sufficiently large iron grains. This study focuses on the influence of Na2SO4 addition on iron grain growth during carbothermic roasting of two red mud samples with different (CaO + MgO)/(SiO2 + Al2O3) ratio of 0.46 and 1.21, respectively. Iron phase distribution in the red mud and roasted samples were investigated in detail by Mössbauer spectroscopy method. Based on thermodynamic calculations and results of multifactorial experiments, the optimal conditions for the roasting of the red mud samples with (CaO + MgO)/(SiO2 + Al2O3) ratio of 0.46 and 1.21 were duration of 180 min with the addition of 13.65% Na2SO4 at 1150 °C and 1350 °C followed by magnetic separation that l...
Metals, 2019
Red mud is a by-product of alumina production from bauxite ore by the Bayer method, which contain... more Red mud is a by-product of alumina production from bauxite ore by the Bayer method, which contains considerable amounts of valuable components such as iron, aluminum, titanium, and scandium. In this study, an approach was applied to extract iron, i.e., carbothermic reduction roasting of red mud with sodium and potassium carbonates followed by magnetic separation. The thermodynamic analysis of iron and iron-free components’ behavior during carbothermic reduction was carried out by HSC Chemistry 9.98 (Outotec, Pori, Finland) and FactSage 7.1 (Thermfact, Montreal, Canada; GTT-Technologies, Herzogenrath, Germany) software. The effects of the alkaline carbonates’ addition, as well as duration and temperature of roasting on the iron metallization degree, iron grains’ size, and magnetic separation process were investigated experimentally. The best conditions for the reduction roasting were found to be as follows: 22.01% of K2CO3 addition, 1250 °C, and 180 min of duration. As a generalizati...
Journal of Sustainable Metallurgy
Red mud is a hazardous waste of alumina production by the Bayer method, which can be used for rec... more Red mud is a hazardous waste of alumina production by the Bayer method, which can be used for recovery of valuable elements such as iron, aluminum, titanium, and scandium. In this study, carbothermic roasting of red mud followed by dry or wet magnetic separation was applied with addition of alkaline salts to enhance iron extraction. A comparative influence of the use of sodium and potassium carbonates and sulfates, as well as the effects of roasting temperature and amounts of the additives on iron recovery and the iron concentrate grade were studied experimentally on two industrial red mud samples. The general mechanism of the roasting process in the presence of alkali metals was proposed in terms of temperature and iron extraction. Influence of the grinding fineness of the roasted samples and magnetic field strength during wet magnetic separation on iron extraction was also studied. It was shown that the addition of sodium and potassium carbonates and sulfates during carbothermic roasting of red mud improves the magnetic separation of metallic iron. The composition and microstructure of the separation products were examined, and their possible application was discussed.
Metals
Vanadium containing sludge is a by-product of vanadium pentoxide obtained by hydrometallurgical m... more Vanadium containing sludge is a by-product of vanadium pentoxide obtained by hydrometallurgical methods from vanadium slag that can be estimated as a promising technogeneous raw material for vanadium production. The phase analysis of vanadium-containing sludge by the X-ray diffraction method showed that it contains vanadium in spinel form (FeO∙V2O3). The various oxidation roasting methods for sludge treatment were studied for increasing vanadium extraction into the solution. It showed that the most effective additive is 1% CaCO3 at a roasting temperature of 1000 °C. Oxidation roasting of vanadium-containing sludge with the additive led to an increase in the acid-soluble form of V2O5 from 1.5% to 3.7% and a decrease in the content of FeO∙V2O3 from 3% to 0.4%. These results confirm the efficiency of the application of oxidation roasting to convert vanadium compounds into acid-soluble forms. The conversion mechanism of spinel to acid-soluble phases during oxidation roasting with additi...
Red mud is a hazardous waste of alumina industry that contains high amounts of iron, aluminum, ti... more Red mud is a hazardous waste of alumina industry that contains high amounts of iron, aluminum, titanium and REEs. One of the promising methods for the extraction of iron from red mud is carbothermic reduction with the addition of sodium salts. This research focuses on the process of hydrochloric high-pressure acid leaching using 10–20% HCl of two samples of non-magnetic tailings obtained by 60-minute carbothermic roasting of red mud at 1300 °C and the mixture of 84.6 wt. % of red mud and 15.4 wt. % Na2SO4 at 1150 °C, respectively, with subsequent magnetic separation of metallic iron. An influence of temperature, leaching duration, solid-to-liquid-ratio and acid concentration on dissolution behavior of Al, Ti, Mg, Ca, Si, Fe, Na, La, Ce, Pr, Nd, Sc, Zr were studied. Based on the investigation of the obtained residues, mechanism of passing of valuable elements into the solution was proposed. It has shown that 90% Al, 91% Sc and above 80% of other REEs can be dissolved under optimal co...
Recycling
Bauxite residue, known as red mud, is a by-product of alumina production using the Bayer process.... more Bauxite residue, known as red mud, is a by-product of alumina production using the Bayer process. Currently, its total global storage amounts to over 4.6 billion tons, including about 600 million tons in Russia. The total global storage of red mud occupies large areas, leading to environmental damage and increasing environmental risks. Moreover, it contains a significant amount of sodium, which is easily soluble in subsoil water; therefore, a sustainable approach for comprehensive recycling of red mud is necessary. The bauxite residue contains valuable elements, such as aluminum, titanium, and scandium, which can be recovered using liquid media. In recent years, many methods of recovery of these elements from this waste have been proposed. This paper provides a critical review of hydrometallurgical, solvometallurgical, and complex methods for the recovery of valuable components from red mud, namely, aluminum, titanium, sodium, and rare and rare-earth elements. These methods include ...
Materials Science Forum
The chemical and phase composition of iron-manganese rare-earth ores of the Tomtor deposit were i... more The chemical and phase composition of iron-manganese rare-earth ores of the Tomtor deposit were investigated. It is shown that the ores contain a large amount of iron, manganese and rare earth metals. The thermodynamic calculation of reduction smelting was carried out. The reduction smelting of the ores at 1650 °C was investigated. The phase and chemical composition of the obtained slag and the alloy were studied. It is showed that obtained alloy is ferromanganese with a high content of carbon and phosphorus, and obtained slag has high content of REM.
Journal of Physics: Conference Series, 2021
Coal fly ash is a hazardous waste of heat power engineering. The complex processing of it include... more Coal fly ash is a hazardous waste of heat power engineering. The complex processing of it includes several stages, such as carbon flotation and magnetic separation of iron. This study focuses on carbon extraction by flotation method and iron by magnetic separation method from Kashirskaya GRES coal fly ash with subsequent reduction smelting of it. At optimal conditions were obtained carbon concentrate with 37% C and magnetic concentrate with 61% Fe2O3. The high-quality steelmaking pig iron with low P and S and high alumina slag were obtained at 1400 °C after reduction smelting mixture magnetic, and carbon concentrates.
Red mud is an iron-containing waste of alumina production with high alkalinity. A promising appro... more Red mud is an iron-containing waste of alumina production with high alkalinity. A promising approach for its recycling is solid-phase carbothermic roasting in the presence of special additives followed by magnetic separation. The crucial factor of the separation of the obtained iron metallic particles from gangue is sufficiently large iron grains. This study focuses on the influence of Na2SO4 addition on iron grain growth during carbothermic roasting of two red mud samples with different (CaO + MgO)/(SiO2 + Al2O3) ratio of 0.46 and 1.21, respectively. Iron phase distribution in the red mud and roasted samples were investigated in detail by Mössbauer spectroscopy method. Based on thermodynamic calculations and results of multifactorial experiments, the optimal conditions for the roasting of the red mud samples with (CaO + MgO)/(SiO2 + Al2O3) ratio of 0.46 and 1.21 were duration of 180 min with the addition of 13.65% Na2SO4 at 1150 °C and 1350 °C followed by magnetic separation that l...
Metallurgist
Research is conducted for creating technology for processing hydrometallurgical production of van... more Research is conducted for creating technology for processing hydrometallurgical production of vanadium pentoxide slurries. The technology includes threestage counterflow leaching of vanadium from slurries and hydrolysis of a vanadiumcontaining solution. The V2O5 content is ≈ 70 wt.% in the resultant concentrate,
Metallurgist, Mar 1, 2020
IOP Conference Series: Materials Science and Engineering
Red mud is a hazardous waste obtained from bauxite ore by the Bayer method. It has a high content... more Red mud is a hazardous waste obtained from bauxite ore by the Bayer method. It has a high content of iron. In this study, the iron grain growth process during solid-phase carbothermic reduction of red mud in the presence of added iron metallic particles was investigated. Carbonyl iron, cast iron shots and metallurgical mill scale were used as the additives. The influence of amount and fraction of the additives on size of reduced iron grains obtained after reduction roasting of red mud at 1250-1350°C and 60-180 min duration was studied. It is showed that the best effect on size of iron grains has the addition of carbonyl iron and mill scale. In this way, besides red mud, some other iron-containing wastes can be recycled, e.g. mill scale.
Metallurgist
The paper presents the results of studying the iron grain growth mechanism during carbothermal so... more The paper presents the results of studying the iron grain growth mechanism during carbothermal solidphase reduction of red mud in the presence of sodium sulfate. It was shown that the main mechanism of iron grain growth involves the formation of low-melting-point surface-active iron-sulfur compounds along the grain boundaries, which significantly accelerates their agglomeration process. The obtained results confirm a positive effect of the sodium sulfate additives on the process of iron grain growth during solid-phase carbothermal reduction of red mud, which makes it possible to improve the efficiency of subsequent magnetic separation.
Inorganic Materials: Applied Research
The processing of electric arc furnace dust by the Waelz process forms the iron-containing residu... more The processing of electric arc furnace dust by the Waelz process forms the iron-containing residue called Waelz slag. In the paper, best practices for recycling of Waelz slag from electric arc furnace dust processing have been analyzed and physicochemical characteristics and microstructure of the Waelz slag obtained from JSC Chelyabinsk zinc plant have been investigated. Chemical analysis of the Waelz slag composition has shown that it contains 26.4 wt % of iron with a metallization degree of 47 and 18.7 wt % carbon. It also contains about 1 wt % of zinc unevaporated during Waelz process. It has a complex multicomponent mineralogical composition. Analysis of papers has shown that currently Waelz slag recycles mainly in the construction industry in the production of cement, concrete, bricks and for road making. There is a limited number of papers devoted to recycling of Waelz slag in metallurgy because it contains too high values of contaminants such as zinc, lead, sulfur, phosphorus and copper. It is expedient to apply for recycling of Waelz slag the reduction smelting with obtaining of pig iron, slag suitable for construction industry and zinc-lead fume.
Russian Metallurgy (Metally)
Abstract—The components of the pyrochlore–monazite ore of the Tomtor deposit are separated by seg... more Abstract—The components of the pyrochlore–monazite ore of the Tomtor deposit are separated by segregation and reduction smelting. Upon segregation smelting, rare-earth metals are found to concentrate in a phosphate–salt melt and niobium, in a silicate melt. The chemical compositions and the microstructures of the silicate and phosphate–salt melts are studied. Carbothermic reduction of the silicate melt at 1600°C results in the formation of an alloy with a high niobium content, and rare-earth metal oxalate and hydroxide concentrates can be formed from the phosphate–salt melt by sequential processing by various acids. A technological scheme is proposed for combined processing of the pyrochlore–monazite ore of the Tomtor deposit.
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Papers by Dmitriy Zinoveev