Róbert Findorák | Technical University of Kosice (original) (raw)
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Papers by Róbert Findorák
Prace Instytutu Metalurgii Żelaza, 2006
International Multidisciplinary Scientific GeoConference SGEM .., Jun 20, 2013
Journal of Sustainable Metallurgy, Jun 7, 2022
Materials
In the presented article, an electrocoagulation method using a steel cathode and a steel anode wa... more In the presented article, an electrocoagulation method using a steel cathode and a steel anode was used to obtain chromium from laboratory-prepared model solutions with known compositions. The study aimed to analyze the effect of solution conductivity, pH, and 100% efficiency of chromium removal from the solution, as well as the highest possible Cr/Fe ratio in the final solid product throughout the process of electrocoagulation. Different concentrations of chromium (VI) (100, 1000, and 2500 mg/L) and different pH values (4.5, 6, and 8) were investigated. Various solution conductivities were provided by the addition of 1000, 2000, and 3000 mg/L of NaCl to the studied solutions. Chromium removal efficiency equal to 100% was achieved for all studied model solutions for different experiment times, depending on the selected current intensity. The final solid product contained up to 15% chromium in the form of mixed FeCr hydroxides obtained under optimal experimental conditions: pH = 6, I...
Journal of Central South University, 2017
The granulability and absorbtivity of sawdust and coke breeze were investigated. These properties... more The granulability and absorbtivity of sawdust and coke breeze were investigated. These properties are important within the preparation of agglomeration charge. They have a significant impact on plynodynamic batch conditions. Ability of materials to wet is a fundamental condition of granulability of materials. Wettability and water absorption of wood with liquids is generally significantly affected by their chemical structure. The important factors affecting the wetting process are undoubtedly the wood moisture content, the value of the surface tension of liquid media and their chemical composition. With increasing moisture content of wood, the time to equilibrium rises. Determination of water absorption and granulability of sawdust was conducted to seek their possible use as a partial replacement of coke dust in the production of the agglomerate. Experiments have been realized with alder, oak and pine sawdust and reference material−coke breeze. These materials were divided to four c...
Applied Sciences
The purpose of this study was to conduct experiments comprising the high-temperature reduction tr... more The purpose of this study was to conduct experiments comprising the high-temperature reduction treatment of commercially produced iron ore fines and lumps aimed at increasing the use value of the ore. The analysed ore was Ukrainian iron ore sold under the Rudomain commercial name, mined from a bed located in the southern part of the Saksagan region (Kryvyi Rih, Ukraine). The study describes in detail the basic physical, chemical, and physico-chemical properties of the analysed ore, and it comprised a thermodynamic analysis, which is typically used as the basis for defining reduction conditions. The Ukrainian ore—Rudomain—exhibited a lower total Fe content (58.20 wt%) and, by contrast, the highest SiO2 content (13.40 wt%), whereas SiO2 is present in this type of ore not only in form of silica (SiO2) but also in form of hydrated iron silicate (Fe3Si2O5(OH)4), i.e., the form of iron that is the most difficult to reduce. In the study, tests of thermal stability and thermal shock stabili...
SGEM International Multidisciplinary Scientific GeoConference EXPO Proceedings
14th SGEM GeoConference on SCIENCE AND TECHNOLOGIES IN GEOLOGY, EXPLORATION AND MINING, 2014
Scientia Iranica, 2016
Charcoal is becoming an alternative source of energy to traditional fossil fuels such as coal and... more Charcoal is becoming an alternative source of energy to traditional fossil fuels such as coal and coke. In theoretical studies, some types of biomass have been identi ed as alternative sources of fuel to coke. The use of charcoal for sintering applications has been evaluated in separate experiments in the world. These experiments indicate that charcoal can replace a portion of the coke breeze (approximately 20-30%). The aim of this thermodynamic study was to evaluate the possibilities of charcoal utilization in iron-ore sintering process. Thermodynamic analysis has shown that the main factors determining the composition and properties of sinter are chemical composition of input materials (including fuels), thermodynamics of fuels burning, and oxidation potential of the gaseous phase (CO2/CO ratio). The main objective of this work was to determine the e ects of coke substitution by charcoal in the laboratory sintering process with respect to combustion e ciency and sinter quality. The coke substitution and energy requirement provided by charcoal was in range of 8 to 86%. The use of charcoal fuel resulted in a decrease in sintering time and the replacement of coke with charcoal may lead to increase in sinter productivity. Overall, the results from the laboratory scale tests suggest that replacement of coke breeze energy with an equivalent amount of energy from charcoal in the iron-ore sintering process is possible and has no negative in uence on technological and ecological parameters.
Biomass and Carbon Fuels in Metallurgy, 2019
Biomass and Carbon Fuels in Metallurgy, 2019
Biomass and Carbon Fuels in Metallurgy, 2019
METAL 2019 Conference Proeedings, 2019
Archives of Metallurgy and Materials, 2018
In this paper are presented results of study fusion characteristics of the biomass ashes from the... more In this paper are presented results of study fusion characteristics of the biomass ashes from the hydrolyzed lignin and the ashes from the coke breeze. The hydrolyzed lignin ashes were compared with the coke breeze ashes i.e. with a fossil fuel. These ashes were prepared in muffle furnace at the temperature of 550°C (hydrolyzed lignin) and 850°C (coke breeze). Biomass (the hydrolyzed lignin) represents the new fuels for sintering process and an attractive way to decrease CO 2 emissions from the energy production. The characterization methods were the following: standard fuel characterization analyses, chemical and mineralogical composition of the ashes and phase analyses of the ashes of biomass and the coke breeze. These ashes were prepared by the same method. Characterisation of the ashes samples was conducted by means of X-ray fluorescence (XRF), X-ray diffraction (XRD) and scanning electron microscopy (SEM). Quantitative analysis of the crystalline and amorphous phases in each of the ash samples were carried out using the Rietveld method. The dominant phase of the ash from the coke breeze was mullite (Al 6 Si 2 O 13). SiO 2 is the dominant phase of the ash from the hydrolyzed lignin.
Biomass and Carbon Fuels in Metallurgy, 2019
Metalurgija, 2014
R. Findorák, M. Fröhlichová, J. Legemza, Faculty of Metallurgy, Technical University of Košice, S... more R. Findorák, M. Fröhlichová, J. Legemza, Faculty of Metallurgy, Technical University of Košice, Slovakia The aim of this work was to asses the concrete ilmenite sand for its application in the process of the fi ne grain materials aggregation or pelletizing. The above intention was based on the knowledge of the titanium positive eff ect upon the formation of the protective brush matting in the blast furnace hearth on the base of the titanium carbon – nitrides. The assessment and analysis of the material was carried out for this purpose, as well as the laboratory experiments aimed to the balling properties. Results achieved from this work predicate the possible exploitation of the ilmenite sand in for of the sinter or pellets production with the higher titanium content.
Prace Instytutu Metalurgii Żelaza, 2006
International Multidisciplinary Scientific GeoConference SGEM .., Jun 20, 2013
Journal of Sustainable Metallurgy, Jun 7, 2022
Materials
In the presented article, an electrocoagulation method using a steel cathode and a steel anode wa... more In the presented article, an electrocoagulation method using a steel cathode and a steel anode was used to obtain chromium from laboratory-prepared model solutions with known compositions. The study aimed to analyze the effect of solution conductivity, pH, and 100% efficiency of chromium removal from the solution, as well as the highest possible Cr/Fe ratio in the final solid product throughout the process of electrocoagulation. Different concentrations of chromium (VI) (100, 1000, and 2500 mg/L) and different pH values (4.5, 6, and 8) were investigated. Various solution conductivities were provided by the addition of 1000, 2000, and 3000 mg/L of NaCl to the studied solutions. Chromium removal efficiency equal to 100% was achieved for all studied model solutions for different experiment times, depending on the selected current intensity. The final solid product contained up to 15% chromium in the form of mixed FeCr hydroxides obtained under optimal experimental conditions: pH = 6, I...
Journal of Central South University, 2017
The granulability and absorbtivity of sawdust and coke breeze were investigated. These properties... more The granulability and absorbtivity of sawdust and coke breeze were investigated. These properties are important within the preparation of agglomeration charge. They have a significant impact on plynodynamic batch conditions. Ability of materials to wet is a fundamental condition of granulability of materials. Wettability and water absorption of wood with liquids is generally significantly affected by their chemical structure. The important factors affecting the wetting process are undoubtedly the wood moisture content, the value of the surface tension of liquid media and their chemical composition. With increasing moisture content of wood, the time to equilibrium rises. Determination of water absorption and granulability of sawdust was conducted to seek their possible use as a partial replacement of coke dust in the production of the agglomerate. Experiments have been realized with alder, oak and pine sawdust and reference material−coke breeze. These materials were divided to four c...
Applied Sciences
The purpose of this study was to conduct experiments comprising the high-temperature reduction tr... more The purpose of this study was to conduct experiments comprising the high-temperature reduction treatment of commercially produced iron ore fines and lumps aimed at increasing the use value of the ore. The analysed ore was Ukrainian iron ore sold under the Rudomain commercial name, mined from a bed located in the southern part of the Saksagan region (Kryvyi Rih, Ukraine). The study describes in detail the basic physical, chemical, and physico-chemical properties of the analysed ore, and it comprised a thermodynamic analysis, which is typically used as the basis for defining reduction conditions. The Ukrainian ore—Rudomain—exhibited a lower total Fe content (58.20 wt%) and, by contrast, the highest SiO2 content (13.40 wt%), whereas SiO2 is present in this type of ore not only in form of silica (SiO2) but also in form of hydrated iron silicate (Fe3Si2O5(OH)4), i.e., the form of iron that is the most difficult to reduce. In the study, tests of thermal stability and thermal shock stabili...
SGEM International Multidisciplinary Scientific GeoConference EXPO Proceedings
14th SGEM GeoConference on SCIENCE AND TECHNOLOGIES IN GEOLOGY, EXPLORATION AND MINING, 2014
Scientia Iranica, 2016
Charcoal is becoming an alternative source of energy to traditional fossil fuels such as coal and... more Charcoal is becoming an alternative source of energy to traditional fossil fuels such as coal and coke. In theoretical studies, some types of biomass have been identi ed as alternative sources of fuel to coke. The use of charcoal for sintering applications has been evaluated in separate experiments in the world. These experiments indicate that charcoal can replace a portion of the coke breeze (approximately 20-30%). The aim of this thermodynamic study was to evaluate the possibilities of charcoal utilization in iron-ore sintering process. Thermodynamic analysis has shown that the main factors determining the composition and properties of sinter are chemical composition of input materials (including fuels), thermodynamics of fuels burning, and oxidation potential of the gaseous phase (CO2/CO ratio). The main objective of this work was to determine the e ects of coke substitution by charcoal in the laboratory sintering process with respect to combustion e ciency and sinter quality. The coke substitution and energy requirement provided by charcoal was in range of 8 to 86%. The use of charcoal fuel resulted in a decrease in sintering time and the replacement of coke with charcoal may lead to increase in sinter productivity. Overall, the results from the laboratory scale tests suggest that replacement of coke breeze energy with an equivalent amount of energy from charcoal in the iron-ore sintering process is possible and has no negative in uence on technological and ecological parameters.
Biomass and Carbon Fuels in Metallurgy, 2019
Biomass and Carbon Fuels in Metallurgy, 2019
Biomass and Carbon Fuels in Metallurgy, 2019
METAL 2019 Conference Proeedings, 2019
Archives of Metallurgy and Materials, 2018
In this paper are presented results of study fusion characteristics of the biomass ashes from the... more In this paper are presented results of study fusion characteristics of the biomass ashes from the hydrolyzed lignin and the ashes from the coke breeze. The hydrolyzed lignin ashes were compared with the coke breeze ashes i.e. with a fossil fuel. These ashes were prepared in muffle furnace at the temperature of 550°C (hydrolyzed lignin) and 850°C (coke breeze). Biomass (the hydrolyzed lignin) represents the new fuels for sintering process and an attractive way to decrease CO 2 emissions from the energy production. The characterization methods were the following: standard fuel characterization analyses, chemical and mineralogical composition of the ashes and phase analyses of the ashes of biomass and the coke breeze. These ashes were prepared by the same method. Characterisation of the ashes samples was conducted by means of X-ray fluorescence (XRF), X-ray diffraction (XRD) and scanning electron microscopy (SEM). Quantitative analysis of the crystalline and amorphous phases in each of the ash samples were carried out using the Rietveld method. The dominant phase of the ash from the coke breeze was mullite (Al 6 Si 2 O 13). SiO 2 is the dominant phase of the ash from the hydrolyzed lignin.
Biomass and Carbon Fuels in Metallurgy, 2019
Metalurgija, 2014
R. Findorák, M. Fröhlichová, J. Legemza, Faculty of Metallurgy, Technical University of Košice, S... more R. Findorák, M. Fröhlichová, J. Legemza, Faculty of Metallurgy, Technical University of Košice, Slovakia The aim of this work was to asses the concrete ilmenite sand for its application in the process of the fi ne grain materials aggregation or pelletizing. The above intention was based on the knowledge of the titanium positive eff ect upon the formation of the protective brush matting in the blast furnace hearth on the base of the titanium carbon – nitrides. The assessment and analysis of the material was carried out for this purpose, as well as the laboratory experiments aimed to the balling properties. Results achieved from this work predicate the possible exploitation of the ilmenite sand in for of the sinter or pellets production with the higher titanium content.