Pub Date : 2021-12-01DOI: 10.3390/materproc2021005048
Stavros Tomazinakis, G. Valakas, A. Gaki, D. Damigos, K. Adam
The Raw Materials (RM) sector is linked to Sustainable Development Goals (SDGs), impacting their implementation throughout the whole RM value chain (e.g., mining, processing, metallurgy, recycling, etc.). This study aims to identify and rank the most significant SDGs for this sector, from the perspective of key stakeholders, academics, university students, professionals, and industry representatives, in three East and South-East Europe (ESEE) countries: Poland, Greece, and Slovakia. Within this framework, 423 stakeholders from the above groups provided their views in a survey with structured questionnaires. The results were analysed, based on the stakeholders’ groups and the role of the sector in the countries examined. Overall, the SDGs 9-Industry, Innovation, and Infrastructure-, 8-Decent Work and Economic Growth-, and 7-Affordable and Clean Energy- were highly ranked by the stakeholders, indicating a strong link between these SDGs and the RM sector.
{"title":"The Significance of SDGs for the Raw Materials Sector: A Stakeholders’ Approach in Three ESEE Countries","authors":"Stavros Tomazinakis, G. Valakas, A. Gaki, D. Damigos, K. Adam","doi":"10.3390/materproc2021005048","DOIUrl":"https://doi.org/10.3390/materproc2021005048","url":null,"abstract":"The Raw Materials (RM) sector is linked to Sustainable Development Goals (SDGs), impacting their implementation throughout the whole RM value chain (e.g., mining, processing, metallurgy, recycling, etc.). This study aims to identify and rank the most significant SDGs for this sector, from the perspective of key stakeholders, academics, university students, professionals, and industry representatives, in three East and South-East Europe (ESEE) countries: Poland, Greece, and Slovakia. Within this framework, 423 stakeholders from the above groups provided their views in a survey with structured questionnaires. The results were analysed, based on the stakeholders’ groups and the role of the sector in the countries examined. Overall, the SDGs 9-Industry, Innovation, and Infrastructure-, 8-Decent Work and Economic Growth-, and 7-Affordable and Clean Energy- were highly ranked by the stakeholders, indicating a strong link between these SDGs and the RM sector.","PeriodicalId":18729,"journal":{"name":"Materials Proceedings","volume":"47 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77759038","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-12-01DOI: 10.3390/materproc2021005047
K. Makri, Christos Roumpos, A. Antoniadis
The geological education in Greece is essentially rooted in the second half of the 19th century, since 1836, when secondary education was established in Greece. Although geology is referred to in all educational programs, its field was not taught before 1880, due to the lack of competent teachers and suitable books. Geological education in Greece was established as a ”necessary” science at the end of the above century, during Greece’s opening phase of mining activity. In particular, the first attempt to exploit lignite deposits began in Aliveri (Evia) in 1873, but the intensive exploitation in Aliveri began after the First World War, reaching an annual production of 23,000 tons by the end of 1927. Respectively, lignite mining began in Ptolemais in the 1950s and Megalopolis in the 1960s. In the present paper, the correlation of the lignite mining activity in Greece for electricity generation with the content of geoscience textbooks is investigated since it is widely accepted that education is directly linked to economic development.
{"title":"The Mining History of Greece in School Textbooks: The Case of Lignite","authors":"K. Makri, Christos Roumpos, A. Antoniadis","doi":"10.3390/materproc2021005047","DOIUrl":"https://doi.org/10.3390/materproc2021005047","url":null,"abstract":"The geological education in Greece is essentially rooted in the second half of the 19th century, since 1836, when secondary education was established in Greece. Although geology is referred to in all educational programs, its field was not taught before 1880, due to the lack of competent teachers and suitable books. Geological education in Greece was established as a ”necessary” science at the end of the above century, during Greece’s opening phase of mining activity. In particular, the first attempt to exploit lignite deposits began in Aliveri (Evia) in 1873, but the intensive exploitation in Aliveri began after the First World War, reaching an annual production of 23,000 tons by the end of 1927. Respectively, lignite mining began in Ptolemais in the 1950s and Megalopolis in the 1960s. In the present paper, the correlation of the lignite mining activity in Greece for electricity generation with the content of geoscience textbooks is investigated since it is widely accepted that education is directly linked to economic development.","PeriodicalId":18729,"journal":{"name":"Materials Proceedings","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89744187","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-11-30DOI: 10.3390/materproc2021005039
Halimeh Askari Sabzkoohi, G. Kolliopoulos
The development of a truly circular economy necessitates the recovery and recycling of resources from secondary streams. In this work, we studied the extraction of metals from printed circuit boards (PCBs) using choline chloride: ethylene glycol deep eutectic solvents: Cu, Ni, Zn, and Sn were selectively extracted from the PCBs, with >75% extraction after 72 h for Cu, Ni, and Sn, and circa. 45% extraction for Zn. This solvometallurgical approach promises to minimize the use of water and acid/base reagents in processing. The results show a considerable ability to compete with current methods of metal extraction and therefore generate a strong potential to attain the goal of a sustainable circular economy via zero-waste green urban mining.
{"title":"Green Zero-Waste Metal Extraction and Recycling from Printed Circuit Boards","authors":"Halimeh Askari Sabzkoohi, G. Kolliopoulos","doi":"10.3390/materproc2021005039","DOIUrl":"https://doi.org/10.3390/materproc2021005039","url":null,"abstract":"The development of a truly circular economy necessitates the recovery and recycling of resources from secondary streams. In this work, we studied the extraction of metals from printed circuit boards (PCBs) using choline chloride: ethylene glycol deep eutectic solvents: Cu, Ni, Zn, and Sn were selectively extracted from the PCBs, with >75% extraction after 72 h for Cu, Ni, and Sn, and circa. 45% extraction for Zn. This solvometallurgical approach promises to minimize the use of water and acid/base reagents in processing. The results show a considerable ability to compete with current methods of metal extraction and therefore generate a strong potential to attain the goal of a sustainable circular economy via zero-waste green urban mining.","PeriodicalId":18729,"journal":{"name":"Materials Proceedings","volume":"51 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75875739","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-11-30DOI: 10.3390/materproc2021005034
Andreas Delentas, A. Benardos, P. Nomikos
The estimation of the stability conditions, over-breaks, and spalling failures, which could inflict potential external dilution, is a key parameter so as to ensure the optimal design of the exploitation and its cost effectiveness The research undertaken aims at correlating established empirical approaches for the estimation of the stability condition with numerical analysis that identifies and measures the depth of failure. A number of analyses have been conducted and the results obtained yield promising results that can be transformed to direct mathematical expressions applied for the early estimation of dilution rates. Furthermore, through the research, an initial proposal is made for a dilution-based stability graph that could be utilized for the early identification of dilution.
{"title":"Linking Stability Conditions and Ore Dilution in Open Stope Mining","authors":"Andreas Delentas, A. Benardos, P. Nomikos","doi":"10.3390/materproc2021005034","DOIUrl":"https://doi.org/10.3390/materproc2021005034","url":null,"abstract":"The estimation of the stability conditions, over-breaks, and spalling failures, which could inflict potential external dilution, is a key parameter so as to ensure the optimal design of the exploitation and its cost effectiveness The research undertaken aims at correlating established empirical approaches for the estimation of the stability condition with numerical analysis that identifies and measures the depth of failure. A number of analyses have been conducted and the results obtained yield promising results that can be transformed to direct mathematical expressions applied for the early estimation of dilution rates. Furthermore, through the research, an initial proposal is made for a dilution-based stability graph that could be utilized for the early identification of dilution.","PeriodicalId":18729,"journal":{"name":"Materials Proceedings","volume":"47 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81141503","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-11-30DOI: 10.3390/materproc2021005041
A. Martínez, S. Senanu, H. Gudbrandsen, K. S. Osen, Anne Støre, Zhaohui Wang, O. Kjos
Electrolysis experiments to produce Al-Sc alloys were carried out in galvanostatic mode using a cryolitic melt with a NaF/AlF3 molar ratio of 2.2 at 980 °C, using both synthetic and waste feeds. After elucidation of the cryolite electrolyte bath chemistry when adding Sc2O3, small-laboratory scale trials allowed for the demonstration of the process and the study and for the optimisation of the electrolysis parameters. Experiments in large-scale electrolysis cells allowed us to run long-term trials in continuous operation, while the on-line monitoring of the cell off-gases ensured the environmentally benign performance of the process. The aluminium product obtained contained 0.6–2.6 wt% Sc, depending on the current density applied. The material is suited to prepare Al-Sc master alloys for 3D printing powders.
{"title":"Production of Al-Sc Alloy by Electrolysis from Cryolite Melt Using Secondary Feedstock Material","authors":"A. Martínez, S. Senanu, H. Gudbrandsen, K. S. Osen, Anne Støre, Zhaohui Wang, O. Kjos","doi":"10.3390/materproc2021005041","DOIUrl":"https://doi.org/10.3390/materproc2021005041","url":null,"abstract":"Electrolysis experiments to produce Al-Sc alloys were carried out in galvanostatic mode using a cryolitic melt with a NaF/AlF3 molar ratio of 2.2 at 980 °C, using both synthetic and waste feeds. After elucidation of the cryolite electrolyte bath chemistry when adding Sc2O3, small-laboratory scale trials allowed for the demonstration of the process and the study and for the optimisation of the electrolysis parameters. Experiments in large-scale electrolysis cells allowed us to run long-term trials in continuous operation, while the on-line monitoring of the cell off-gases ensured the environmentally benign performance of the process. The aluminium product obtained contained 0.6–2.6 wt% Sc, depending on the current density applied. The material is suited to prepare Al-Sc master alloys for 3D printing powders.","PeriodicalId":18729,"journal":{"name":"Materials Proceedings","volume":"150 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77414694","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-11-30DOI: 10.3390/materproc2021005040
Vinicius Sales, C. Paternoster, D. Mantovani, G. Kolliopoulos
Aqueous solvents, despite being effective in the electrodeposition of metals with positive reduction potential, fail to deposit metals with negative reduction potential due to their narrow electrochemical potential window. Deep eutectic solvents (DESs), a class of ionic liquids, are a promising alternative of inexpensive, biodegradable, non-toxic anhydrous solvents that present wide electrochemical potential windows. The present work reports on the potential of choline chloride/ethylene glycol DES in the electrodeposition of Fe–Mn alloys. Cyclic voltammetry tests showed that increasing the quantity of Mn in the bath composition decreases the deposition current of the alloy.
{"title":"Fe–Mn Alloys Electroforming Process Using Choline Chloride Based Deep Eutectic Solvents","authors":"Vinicius Sales, C. Paternoster, D. Mantovani, G. Kolliopoulos","doi":"10.3390/materproc2021005040","DOIUrl":"https://doi.org/10.3390/materproc2021005040","url":null,"abstract":"Aqueous solvents, despite being effective in the electrodeposition of metals with positive reduction potential, fail to deposit metals with negative reduction potential due to their narrow electrochemical potential window. Deep eutectic solvents (DESs), a class of ionic liquids, are a promising alternative of inexpensive, biodegradable, non-toxic anhydrous solvents that present wide electrochemical potential windows. The present work reports on the potential of choline chloride/ethylene glycol DES in the electrodeposition of Fe–Mn alloys. Cyclic voltammetry tests showed that increasing the quantity of Mn in the bath composition decreases the deposition current of the alloy.","PeriodicalId":18729,"journal":{"name":"Materials Proceedings","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88805529","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-11-30DOI: 10.3390/materproc2021005036
A. Lazou, C. van der Eijk, Michail Vafeias, Amalia Bempelou, E. Balomenos, L. Kolbeinsen, D. Panias, J. Safarian
The Pedersen process is a method to produce alumina from Al-containing sources, and it is a more material-efficient method than the current commercial Bayer process, since the formation of bauxite residue (red mud) is avoided, and the bauxite can be holistically consumed. The smelting reduction (SR) part of the Pedersen process yields pig iron and a calcium aluminate slag, and the latter is a feedstock material for alumina extraction via alkaline leaching. In the present study, three different bauxite ores (Greek, Turkish and Jamaican) were smelted with lime to ease the process and control the slag chemistry and coke for the carbothermic reduction of iron oxides. The slags produced were analyzed with XRD, XRF, and EPMA to identify the phases and chemical compositions. According to the results, the slags composed of Al-containing leachable phases. Moreover, it is shown that the amount and distribution of both the leachable and non-leachable phases in the slags depend on the ore chemical composition. The results are discussed regarding the characteristics and potential leachability of the slags. Standard leaching tests were performed to examine the actual leachability.
{"title":"High Temperature Treatment of Selected Iron Rich Bauxite Ores to Produce Calcium Aluminate Slags","authors":"A. Lazou, C. van der Eijk, Michail Vafeias, Amalia Bempelou, E. Balomenos, L. Kolbeinsen, D. Panias, J. Safarian","doi":"10.3390/materproc2021005036","DOIUrl":"https://doi.org/10.3390/materproc2021005036","url":null,"abstract":"The Pedersen process is a method to produce alumina from Al-containing sources, and it is a more material-efficient method than the current commercial Bayer process, since the formation of bauxite residue (red mud) is avoided, and the bauxite can be holistically consumed. The smelting reduction (SR) part of the Pedersen process yields pig iron and a calcium aluminate slag, and the latter is a feedstock material for alumina extraction via alkaline leaching. In the present study, three different bauxite ores (Greek, Turkish and Jamaican) were smelted with lime to ease the process and control the slag chemistry and coke for the carbothermic reduction of iron oxides. The slags produced were analyzed with XRD, XRF, and EPMA to identify the phases and chemical compositions. According to the results, the slags composed of Al-containing leachable phases. Moreover, it is shown that the amount and distribution of both the leachable and non-leachable phases in the slags depend on the ore chemical composition. The results are discussed regarding the characteristics and potential leachability of the slags. Standard leaching tests were performed to examine the actual leachability.","PeriodicalId":18729,"journal":{"name":"Materials Proceedings","volume":"64 1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73249460","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-11-30DOI: 10.3390/materproc2021005035
E. Manoutsoglou, N. Papageorgiou, E. Georgiou
The aim of this work is to highlight the contribution of geological maps and mapping to industrial scale design. To achieve this goal, the site selection of a new quarry area is used as an example. For the development of a new quarry, the materials to be mined must meet specific requirements, mainly acceptable quality, adequate reserves, environmental restrictions, and economic viability. Geological maps of various scales were used in all stages of this research project. Initially, geological surveillance maps (1:50,000), which formed the basis for the sampling, were used. Finally, this research project was completed with the detailed mapping of two candidate areas for the development of the new quarry.
{"title":"The Contribution of Geological Maps and Mapping to Industrial Scale Design","authors":"E. Manoutsoglou, N. Papageorgiou, E. Georgiou","doi":"10.3390/materproc2021005035","DOIUrl":"https://doi.org/10.3390/materproc2021005035","url":null,"abstract":"The aim of this work is to highlight the contribution of geological maps and mapping to industrial scale design. To achieve this goal, the site selection of a new quarry area is used as an example. For the development of a new quarry, the materials to be mined must meet specific requirements, mainly acceptable quality, adequate reserves, environmental restrictions, and economic viability. Geological maps of various scales were used in all stages of this research project. Initially, geological surveillance maps (1:50,000), which formed the basis for the sampling, were used. Finally, this research project was completed with the detailed mapping of two candidate areas for the development of the new quarry.","PeriodicalId":18729,"journal":{"name":"Materials Proceedings","volume":"266 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77159266","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-11-30DOI: 10.3390/materproc2021005038
Konstantina Asimakou, N. Kallithrakas‐Kontos, A. Vafeidis, E. Manoutsoglou
Radon (Rn), a natural colorless, odorless, noble radioactive gas, with a half-life of 3.8 days, is an important source of natural ionizing radiation. It originates from the initial concentrations of uranium and its transmuted daughters in rocks, soil, and finally, waters and tends to be concentrated in closed spaces such as underground mines. The concentration of radon in mines contributes significantly to the increase in the dose of ionizing radiation received by humans visiting, accessing, working in these areas. The comparison of radon concentration in active and inactive mining sites, its effect on human health, and the different concentrations’ upper limits, applicable by state, are discussed in this paper.
{"title":"Distribution of Radon Concentrations in Active and Inactive Underground Mines: A Literature Review","authors":"Konstantina Asimakou, N. Kallithrakas‐Kontos, A. Vafeidis, E. Manoutsoglou","doi":"10.3390/materproc2021005038","DOIUrl":"https://doi.org/10.3390/materproc2021005038","url":null,"abstract":"Radon (Rn), a natural colorless, odorless, noble radioactive gas, with a half-life of 3.8 days, is an important source of natural ionizing radiation. It originates from the initial concentrations of uranium and its transmuted daughters in rocks, soil, and finally, waters and tends to be concentrated in closed spaces such as underground mines. The concentration of radon in mines contributes significantly to the increase in the dose of ionizing radiation received by humans visiting, accessing, working in these areas. The comparison of radon concentration in active and inactive mining sites, its effect on human health, and the different concentrations’ upper limits, applicable by state, are discussed in this paper.","PeriodicalId":18729,"journal":{"name":"Materials Proceedings","volume":"10 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78418109","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-11-30DOI: 10.3390/materproc2021005037
K. Oikonomou, D. Damigos
Mineral raw materials prices have been shown to be affected by macroeconomic factors such as aggregate demand and commodity-specific factors (e.g., supply shocks). In addition, it has been shown that certain mineral raw material prices co-move, meaning that they behave similarly during expansion and contraction phases of the international business cycles. In order to assess the behavior similarity of the prices of different mineral raw materials, we propose a method that utilizes extracted features of time series price data and unsupervised learning techniques to create clusters of price movements having similar long-term behavior.
{"title":"Assessing Behavior Similarity of Mineral Raw Material Prices through a Feature-Based Clustering Approach","authors":"K. Oikonomou, D. Damigos","doi":"10.3390/materproc2021005037","DOIUrl":"https://doi.org/10.3390/materproc2021005037","url":null,"abstract":"Mineral raw materials prices have been shown to be affected by macroeconomic factors such as aggregate demand and commodity-specific factors (e.g., supply shocks). In addition, it has been shown that certain mineral raw material prices co-move, meaning that they behave similarly during expansion and contraction phases of the international business cycles. In order to assess the behavior similarity of the prices of different mineral raw materials, we propose a method that utilizes extracted features of time series price data and unsupervised learning techniques to create clusters of price movements having similar long-term behavior.","PeriodicalId":18729,"journal":{"name":"Materials Proceedings","volume":"3 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79707969","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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