2,781 results on '"BACHMANN K"'
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102. Characterization of lithium-ion batteries in recycling processes and assessment of the liberation efficiency of black mass components using automated mineralogy
- Author
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Bachmann, K., Vanderbruggen, A., Hayagan, N. L., and Rudolph, M.
- Subjects
XRF ,ICP-OES ,Spent Lithium Ion Battery ,MLA ,Black mass - Abstract
Lithium-ion batteries (LIBs) are currently the most important electrochemical energy storage sys-tems for electronic mobile devices and electric vehicles. The growing global demand for LIBs is accompanied by an increase in the need for Co, Mn, Ni, Li and graphite. In order to narrow the gap between supply and demand and to achieve the European sustainability goals, the recycling of LiBs has attracted a lot of attention in recent years. Here, the focus is on valuable metals such as cobalt, nickel and lithium as well as graphite. In addition, due to its chemical and phase compositions, the battery material remains to be a huge challenge for a proper materials characterization. Hence, there is not only a need to find innovative and comprehensive LiB recycling process solutions but also to develop new analytical workflows to enhance the understanding of the battery material. In this study, LIBs are fed to a mechanical and thermo-mechanical recycling process route to release active materials from electrodes foils. In addition to the valuable metals, the focus is particularly on the recovery of graphite. The mechanical route works with an impact shear crusher, while for the thermo-mechanical tests the batteries were vacuum pyrolyzed at 500-650 °C before crushing. The so-called black mass fraction smaller than 1 mm was separated and further classified into four size fractions. Accurate characterization of both the main chemistry and detailed characterization of the phases contained in the recycled material remains a major challenge. Therefore, each fraction has been characterized by different analytical methods, including X-ray fluorescence (XRF), inductively coupled plasma optical emission spectroscopy (ICP-OES). For a good visualization and quantifica-tion of the results of the processing success and process efficiency, a more detailed analytical char-acterization is required. This study proposes an innovative and novel characterization method based on automated mineralogy. Various important particle parameters such as size, composition and ad-hesion are analyzed and quantitatively evaluated. The Mineral Liberation Analyzer (MLA) system used for the measurements uses a combination of scanning electron microscopy (SEM) image analy-sis and energy-dispersive X-ray spectroscopy (EDS) and is established as a powerful method in the primary raw materials sector. However, there are no dedicated databases for use in the secondary raw materials sector in order to analyze black mass material in a fast and precise manner. An analyti-cal challenge of this study is therefore to create a database for battery characterization and to be able to use it for a wide range of applications. Results of this study display a selective liberation of electrode foils during the beneficiation process. The thermo-mechanical process releases more active particles from the foils than a mechanical pro-cess alone. Hence, most of the graphite particles are liberated and concentrated in the < 63 μm frac-tion, in particular in the case of thermo-mechanically treated samples. Cu foils are generally better liberated than aluminium foils. However, it was found that the process type has different effects on Al foil liberation. The thermomechanical process liberates more metal oxides from the Al foil than the mechanical process alone but Al breakage is more affected by thermal treatment, resulting in finer Al particles.
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- 2021
103. Comparison of partial roasting and alkaline sulfide leaching for treatment of As-rich concentrates
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Meiner, K., Weigelt, A., Charitos, A., Stelter, M., Wrobel, M., Förster, K., Hammerschmidt, J., Parra, R., Bachmann, K., and Buchmann, M.
- Abstract
Copper possesses a variety of applications. With regard to the primary copper production, enriched sulfidic copper concentrates are fed to the smelters. Within the last decades the copper concentration in usable ores/concentrates is decreasing. Concentrate content in impurities like arsenic, antimony, bismuth and other hazardous elements, which are mineralogically bonded, is on the rise. In addition to the state of the art partial roasting process, the removal of arsenic through alkaline sulfide leaching of respective copper concentrates is a viable option. Mineralogical and chemical compositions of arsenic-bearing concentrates are measured by PXRD, XRF and AES. The particle based mineralogy of examine concentrates is characterized by MLA. Moreover, fluid bed roasting and under nitrogen/oxygen atmosphere are conducted to examine operational parameters on arsenic removal with focus on the oxygen partial pressure. For the hydrometallurgical part leaching tests with a sulfide solution under alkaline conditions are conducted in a lab scale reactor allowing for direct process comparison.
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- 2021
104. Fieberambulanzstudie Magdeburg (FIA-MD) - Inanspruchnahme von Fieberambulanzen während der COVID-19-Pandemie
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Bachmann, K, John, R, Brenne, S, Lichte, T, Bachmann, K, John, R, Brenne, S, and Lichte, T
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- 2021
105. Characterization of lithium-ion batteries in recycling processes and assessment of the liberation efficiency of black mass components using automated mineralogy
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(0000-0001-8904-6555) Bachmann, K., (0000-0003-4092-4374) Vanderbruggen, A., Hayagan, N. L., (0000-0002-5374-6135) Rudolph, M., (0000-0001-8904-6555) Bachmann, K., (0000-0003-4092-4374) Vanderbruggen, A., Hayagan, N. L., and (0000-0002-5374-6135) Rudolph, M.
- Abstract
Lithium-ion batteries (LIBs) are currently the most important electrochemical energy storage sys-tems for electronic mobile devices and electric vehicles. The growing global demand for LIBs is accompanied by an increase in the need for Co, Mn, Ni, Li and graphite. In order to narrow the gap between supply and demand and to achieve the European sustainability goals, the recycling of LiBs has attracted a lot of attention in recent years. Here, the focus is on valuable metals such as cobalt, nickel and lithium as well as graphite. In addition, due to its chemical and phase compositions, the battery material remains to be a huge challenge for a proper materials characterization. Hence, there is not only a need to find innovative and comprehensive LiB recycling process solutions but also to develop new analytical workflows to enhance the understanding of the battery material. In this study, LIBs are fed to a mechanical and thermo-mechanical recycling process route to release active materials from electrodes foils. In addition to the valuable metals, the focus is particularly on the recovery of graphite. The mechanical route works with an impact shear crusher, while for the thermo-mechanical tests the batteries were vacuum pyrolyzed at 500-650 °C before crushing. The so-called black mass fraction smaller than 1 mm was separated and further classified into four size fractions. Accurate characterization of both the main chemistry and detailed characterization of the phases contained in the recycled material remains a major challenge. Therefore, each fraction has been characterized by different analytical methods, including X-ray fluorescence (XRF), inductively coupled plasma optical emission spectroscopy (ICP-OES). For a good visualization and quantifica-tion of the results of the processing success and process efficiency, a more detailed analytical char-acterization is required. This study proposes an innovative and novel characterization method based on automated mineralo
- Published
- 2021
106. Particle based characterization of lithium ion battery recycling using automated mineralogy
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(0000-0003-4092-4374) Vanderbruggen, A., Hayagan, N., Bachmann, K., (0000-0002-5374-6135) Rudolph, M., Serna, R., (0000-0003-4092-4374) Vanderbruggen, A., Hayagan, N., Bachmann, K., (0000-0002-5374-6135) Rudolph, M., and Serna, R.
- Abstract
Presentation about Li-ion battery characterization ia automated mineralogy with a particular focus on the flotation of graphite in black mass.
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- 2021
107. Developing methods to tackle analytical issues in battery recycling materials using SEM and bulk analytical methods
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(0000-0002-2583-6889) Möckel, R., Bachmann, K., (0000-0003-4092-4374) Vanderbruggen, A., Ebert, D., (0000-0002-2583-6889) Möckel, R., Bachmann, K., (0000-0003-4092-4374) Vanderbruggen, A., and Ebert, D.
- Abstract
To close the loop of the respective material demands, the role of battery recycling is steadily increasing, especially in the light of changing mobility. The analytical requirements for the battery material are challenging, since they are complex and heterogeneous secondary materials. They contain Li in different compounds, carbon in the form of graphite (“black mass”), but also metals like Mn, Fe, Cu, Al, Co, Ni etc. partly in several oxidation states (pure metal foils vs. different compounds). All these components are also highly affected by the recycling stages (e.g. pyrolysis, leaching, ect.). On the other hand, with the main aim of an effective recycling the demand for as detailed as possible analytical data is likewise high. Generally, there is no single method available for tackling all the analytical issues and a combination of methods is inevitable. In different recycling projects, we developed methods for scanning electron microscope (SEM) techniques (in our case MLA mineral liberation analyser and TIMA Tescan integrated mineral analyzer), quantitative XRD (X-ray diffraction) and XRF (X-ray fluorescence) with support of ICP-OES. While SEM techniques are essential to provide information on a particle base (incl. chemical composition, grain size, liberation etc.) the other techniques provide pure bulk chemical analytics. An approach – with slight amendments – known from the so called automated mineralogy applied to the materials revealed very useful results for understanding processing parameters, i.e. for the beneficiation of black mass in high quality (Vanderbruggen et al. 2021). On the other hand by simply adding an internal standard (we chose ZrO2) it is possible to develop a quick and easy method for XRF analysis where the sum of “invisible” elements (e.g. C, Li, O, F) can be determined easily with accurate quantification of the other elements, mainly focusing on the metal contents. Lithium containing compounds can be detected by XRD, but the methods ha
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- 2021
108. Aktuelle Erkenntnisse bei der flotativen Aufbereitung von Schwarzmasse und Entwicklungen bei der Schwarzmassecharakterisierung mit den Methoden der Prozessmineralogie und Aufschlussanalytik
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(0000-0002-5374-6135) Rudolph, M., (0000-0003-4092-4374) Vanderbruggen, A., Bachmann, K., (0000-0002-5374-6135) Rudolph, M., (0000-0003-4092-4374) Vanderbruggen, A., and Bachmann, K.
- Abstract
Lithium-Ionen-Batterien (LIBs) gehören zu den derzeit wichtigsten elektrochemischen Energiespeichersystemen für elektronische Mobilgeräte und Elektrofahrzeuge. Die wachsende weltweite Nachfrage nach LIBs geht mit einer Erhöhung des Bedarfs an Co, Mn, Ni, Li und Graphit einher. Diese Erhöhung der Nachfrage dieser Rohstoffe stellt eine besondere Herausforderung für den schon jetzt angespannten weltweiten Rohstoffmarkt dar, verbunden mit Versorgungsrisiken, Preisschwankungen und Marktmonopolen. Tatsächlich sind Co und natürlicher Graphit in Europa seit 2010 als kritische Rohstoffe (CRM) geführt, Li sowie Mn befinden sich an der Grenze der Kritikalität. Um potenziell die Kluft zwischen Angebot und Nachfrage zu verringern sowie die europäischen Nachhaltigkeitsziele zu erreichen, hat das Recycling von Lithium-Ionen-Batterien (LIB) in den letzten Jahren viel Aufmerksamkeit auf sich gezogen. Hierbei wird sich hauptsächlich auf die wertvollen Metalle wie Kobalt, Nickel und Lithium konzentriert. Allerdings gehen während des Recyclingprozesses erhebliche Mengen anderer Komponenten wie Elektrolyt, Separator oder Graphit verloren. So kann Graphit zum Beispiel während der pyrometallurgischen Behandlung entweder abgeschlackt oder als Reduktionsmittel verbraucht werden. Darüber hinaus gehen einige andere wertvolle Metalle wie Co in den Grobfraktionen durch einen zu geringen Aufschlussgrad an die Berge verloren. Aus diesem Grund müssen neue und umfassende LIB-Recyclingverfahren gefunden werden. In dieser Studie werden wir auf die aktuellen Ergebnisse der Schwarzmasseaufbereitung und der Charakterisierung der Lithium-Ionen Batterie Recyclatströmen.
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- 2021
109. Automated mineralogy as a novel method to assess the efficiency of lithium-ion batteries recycling
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(0000-0003-4092-4374) Vanderbruggen, A., Gugala, E., (0000-0001-9917-2264) Blannin, R., Bachmann, K., Serna-Guerrero, R., (0000-0002-5374-6135) Rudolph, M., (0000-0003-4092-4374) Vanderbruggen, A., Gugala, E., (0000-0001-9917-2264) Blannin, R., Bachmann, K., Serna-Guerrero, R., and (0000-0002-5374-6135) Rudolph, M.
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- 2021
110. Characterization of lithium ion battery recycling processes and estimation of liberation efficiency of electrodes using automated mineralogy
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(0000-0003-4092-4374) Vanderbruggen, A., Hayagan, N. L., Bachmann, K., (0000-0002-5374-6135) Rudolph, M., (0000-0003-4092-4374) Vanderbruggen, A., Hayagan, N. L., Bachmann, K., and (0000-0002-5374-6135) Rudolph, M.
- Abstract
Lithium-ion batteries (LIBs) are currently one of the most important electrochemical energy storage devices, powering electronic mobile devices and electric vehicles. Growing global demands for Co, Mn, Ni, Li, and graphite which are all used and present in LIBs as energy storage added difficulties to the already deficit and imbalance supply of sources of raw materials worldwide, which resulted to supply risks, price fluctuations and monopoly of market. In fact, Co and natural graphite are listed as critical raw materials (CRMs) in Europe since 2010 and Mn, and Li are on the boundary of criticality. While recycling is identified as a solution to potentially reduce the gap between the demand and supply. Recycling of lithium ion battery (LIB) has attracted a lot of attention in the recent years and focuses primarily on valuable metals such as cobalt, nickel and lithium. During the recycling processes, considerable amount of the components are lost like electrolyte, separator or graphite. For instance, graphite can either be slagged-off or consumed as a reductant agent during pyrometallurgical treatment. Some other loses are due to a lack of liberation of the targeted particles, elements such as Co are lost in the coarse fractions and a not recovered in the right product. Hence, there is a need to find innovative and comprehensive LIB recycling operations. For understanding and be able to quantify the loses and recycling process efficiency a deeper characterization is required. This research proposes a new characterization method based on automated mineralogy. In this study, the particles morphologies (size, composition and phases associations) are analysed. The liberation of active materials from electrodes is quantified by comparing two recycling processes: mechanical and thermochemical-mechanical. The mechanical route operates with an impact shear crusher while for the thermomechanical operation the batteries were vacuum pyrolyzed at 500-650oC before to be crushed. T
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- 2021
111. Automated mineralogy as a novel approach for the compositional and textural characterization of spent lithium-ion batteries
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(0000-0003-4092-4374) Vanderbruggen, A., Gugala, E., (0000-0001-9917-2264) Blannin, R., (0000-0001-8904-6555) Bachmann, K., (0000-0002-2223-142X) Serna-Guerrero, R., (0000-0002-5374-6135) Rudolph, M., (0000-0003-4092-4374) Vanderbruggen, A., Gugala, E., (0000-0001-9917-2264) Blannin, R., (0000-0001-8904-6555) Bachmann, K., (0000-0002-2223-142X) Serna-Guerrero, R., and (0000-0002-5374-6135) Rudolph, M.
- Abstract
Mechanical recycling processes aim to separate particles based on their physical properties, such as size, shape and density, and physico-chemical surface properties, such as wettability. Secondary materials, including electronic waste, are highly complex and heterogeneous, which complicates recycling processes. In order to improve recycling efficiency, characterization of both recycling process feed materials and intermediate products is crucial. Textural characteristics of particles in waste mixtures cannot be determined by conventional characterization techniques, such as X-ray fluorescence and X-ray diffraction spectroscopy. This paper presents the application of automated mineralogy as an analytical tool, capable of describing discrete particle characteristics for monitoring and diagnosis of lithium ion battery (LIB) recycling approaches. Automated mineralogy, which is well established for the analysis of primary raw materials but has not yet been tested on battery waste, enables the acquisition of textural and chemical information, such as elemental and phase composition, morphology, association and degree of liberation. For this study, a thermo-mechanically processed black mass (<1 mm fraction) from spent LIBs was characterized with automated mineralogy. Each particle was categorized based on which LIB component it comprised: Al foil, Cu foil, graphite, lithium metal oxides and alloys from casing. A more selective liberation of the anode components was achieved by thermo-mechanical treatment, in comparison to the cathode components. Therefore, automated mineralogy can provide vital information for understanding the properties of black mass particles, which determine the success of mechanical recycling processes. The introduced methodology is not limited to the presented case study and is applicable for the optimization of differentseparation unit operations in recycling of waste electronics and batteries.
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- 2021
112. The quantification of entropy for multicomponent systems: application to microwave-assisted comminution
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(0000-0001-5733-3218) Belo Fernandes, I., (0000-0002-5374-6135) Rudolph, M., (0000-0002-6410-4736) Hassanzadehmahaleh, A., (0000-0001-8904-6555) Bachmann, K., (0000-0002-2174-3167) Meskers, C. E. M., (0000-0002-8349-4493) Peuker, U., (0000-0003-0500-4863) Reuter, M., (0000-0001-5733-3218) Belo Fernandes, I., (0000-0002-5374-6135) Rudolph, M., (0000-0002-6410-4736) Hassanzadehmahaleh, A., (0000-0001-8904-6555) Bachmann, K., (0000-0002-2174-3167) Meskers, C. E. M., (0000-0002-8349-4493) Peuker, U., and (0000-0003-0500-4863) Reuter, M.
- Abstract
The second law of thermodynamics, through exergy analysis, is commonly applied to quantify process inefficiencies in metallurgical reactors, however, it is not yet being used to understand physical processes and changes in particle-based systems. Correlating the state of mixing of particle texture and homogeneous liquid mixtures is of importance. This paper applies the exergy analysis and excess entropy method to two sets of experiments highlighting the differential breakage as microwave pre-treatment is applied to a gold-copper ore. Grinding kinetic properties were measured following the top-size fraction method and calculated using the population balance model. The approach combines the mixing entropy on the system level (streams) and the entropy for multicomponent particle systems, using automated mineralogy data to quantify the effects of intergrowth and improvements in grinding performance. This is a first step towards understanding mineral processing not only in terms of energy conservation (first law of thermodynamics) but also in terms of the quality of energy available at multicomponent systems (second law of thermodynamics). When applied to comminution processes, this methodology enables us to understand the change in particle composition (its degree of liberation) as well as changes in particle size, being an important measure of process efficiency and selectivity.
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- 2021
113. Assessment of the liberation efficiency of lithium-ion battery components in recycling processes by using automated mineralogy
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(0000-0003-4092-4374) Vanderbruggen, A., (0000-0001-8904-6555) Bachmann, K., Hayagan, N. L., (0000-0002-5374-6135) Rudolph, M., (0000-0003-4092-4374) Vanderbruggen, A., (0000-0001-8904-6555) Bachmann, K., Hayagan, N. L., and (0000-0002-5374-6135) Rudolph, M.
- Abstract
Mechanical recycling processes aim at separating individual particles based on their properties, such as size, shape, density and composition. However, secondary material such as spent lithium ion battery are highly heterogeneous and complex in element and also material form. In order to improve recycling efficiency, characterization of the recycled products, on a particle level, is crucial. Nevertheless, conventional characterization techniques, such ICP-OES, XRF or XRD, provide bulked information for the products only. Tis research presents the development of a new analytical procedure based on individual particle characterization in order to monitor and diagnose lithium ion battery (LiB) recycling. In this study, cylindrical lithium-ion batteries (INR18650-29E) are fed to a mechanical and thermo-mechanical recycling process route to release coated particles from the electrodes foils. In addition to the valuable metals, the focus is particularly on the recovery of graphite. The mechanical route works with a shear crusher, while for the thermo-mechanical tests the batteries were vacuum pyrolyzed at 500-650 °C before crushing. The fraction smaller than 1 mm, called black mass, was separated and classified into 4 size fractions based on the particle size distribution. The samples were analysed by automated mineralogy, this analytical tool enables the acquisition of particle-based information such as elemental and phase composition, morphology, association and degree of liberation. The Mineral Liberation Analyzer (MLA) system used for the measurements uses a combination of scanning electron microscopy (SEM) image analysis and energy-dispersive X-ray spectroscopy (EDS) and is established as a powerful method in the primary raw materials sector. However, there are no dedicated databases for use in the secondary raw materials sector in order to analyze black mass material in a fast and precise manner. An analytical challenge of this study is therefore to create a databas
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- 2021
114. Is Toupet fundoplication the procedure of choice for treating gastroesophageal reflux disease? Results of a prospective randomized experimental trial comparing three major antireflux operations in a porcine model
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Bachmann, K., Wachowiak, R., Rempf, C., Vashist, Y., Mann, O., Yekebas, E. F., Izbicki, J. R., and Gawad, K. A.
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- 2011
- Full Text
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115. X
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Bachmann, K. R., Brügmann, N., Eickmann, J., Falk, M., Franzen, S., Helms, S., Herbstmeier, M., Hoffmann, C., Kleinelanghorst, A., Kurth, U., Lörscher, H., Lübker-Suhre, G., Noltensmeier, R., Schomberg, C., Scheel, I., Simon, R.-M., Simon, S., Bachmann, K. R., Brügmann, N., Eickmann, J., Falk, M., Franzen, S., Helms, S., Herbstmeier, M., Hoffmann, C., Kleinelanghorst, A., Kurth, U., Lörscher, H., Lübker-Suhre, G., Noltensmeier, R., Schomberg, C., Scheel, I., Simon, R.-M., and Simon, S.
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- 2006
- Full Text
- View/download PDF
116. Prädiktive Geometallurgie in Freiberg – von 'Virtual Twins' und Prozessoptimierung
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Bachmann, K., Pereira, L., Tolosana Delgado, R., Boogaart, K. G., and Gutzmer, J.
- Abstract
Der moderne Bergbausektor steht vor gewaltigen technischen Herausforderungen. Dazu zählen der Rückgang von Erzgehalten, der zunehmende Umgang mit komplexen Mineralparagenesen und sehr feinen Korngrößen aber auch einer steigenden Erzvariabilität. Mit Hilfe geometallurgischer Modelle versucht die Bergbauindustrie diese Herausforderungen zu bewältigen und das Verhalten des Erzes während des Abbaus, der Aufbereitung und der Verhüttung quantitativ vorherzusagen. Um hier einen Beitrag zu leisten, wird am Standort Freiberg seit 2008 geometallurgische Kernkompetenz aufgebaut. Diese Entwicklung wurde mit der Gründung des Helmholtz-Instituts Freiberg für Ressourcentechnologie (HIF), einer gemeinsamen Gründung des Helmholtz-Zentrums Dresden-Rossendorf (HZDR) und der TU Bergakademie Freiberg (TU Bergakademie Freiberg) im Jahr 2011, stark beschleunigt. Aus diesem Grund zählt Freiberg heute weltweit zu den wichtigsten Forschungs- und Entwicklungsstandorten der Geometallurgie. In diesem Artikel werfen wir einen Blick auf den aktuellen Stand der Entwicklungen, mit Fokus auf zwei sehr erfolgreiche Projekte im Bereich der geometallurgischen Modellierung, sowohl primärer als auch sekundärer Rohstoffe.
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- 2020
117. An open source platform for predictive geometallurgy
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Tolosana Delgado, R., Schach, E., Kupka, N., Buchmann, M., Bachmann, K., Frenzel, M., Pereira, L., Rudolph, M., and Boogaart, K. G.
- Abstract
Geometallurgy (the science of predicting the behaviour of ores along the value chain on the basis of their geoscientific characteristics) has barely moved beyond process mineralogy studies. These studies typically describe the mineralogical and microstructural characteristics of pristine or processed ores, for qualitative or semi-quantitative assessment of the processing performance and, eventually, a trial-and-error optimisation of the operation. But to deliver on its promise, geometallurgy should progress beyond this to provide fully quantitative models of such primary ore characteristics and the performance of their processing, both in average value and, most importantly, keeping track of their uncertainty. Only then it will be possible to optimise the operation in a predictive way. For this goal, we have developed a data mining platform consisting on a SQL database, an R front-end in-house package, and back-ends interpreting data from several analytical instruments into the database. A structured relational SQL database is useful to organise all available information (geometry, phase, chemistry, physical properties) of mineral grains, particles and samples. The R front-end allows to use the statistical and data mining power of this open-source environment in a transparent way for any geomet task, from ore characterisation to process fitting and forecasting, from geostatistical prediction to operational optimisation. With regard to the back-ends, currently we import XRD, XRF and mineral liberation analysis measurements, and we will incorporate other data sources. The scripting abilities of R allow to process many streams in loop freeing the user of repeating tedious click-and-drop tasks; compute virtually any quantity; distribute the work among several clusters; or keep a log file of the calculations done, for accountability. This contribution presents the building blocks of this package, and their use with several examples in geometallurgical tasks.
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- 2020
118. Basal cell carcinoma risk and solar UV exposure in occupationally relevant anatomic sites: do histological subtype, tumor localization and Fitzpatrick phototype play a role? A population-based case-control study
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Bauer, A., Haufe, E., Heinrich, L., Seidler, A., Schulze, H. J., Elsner, P., Drexler, H., Letzel, S., John, S. M., Fartasch, M., Brüning, T., Dugas-Breit, S., Gina, M., Weistenhöfer, W., Bachmann, K., Bruhn, I., Lang, B. M., Brans, R., Allam, J. P., Grobe, W., Westerhausen, S., Knuschke, P., Wittlich, M., Diepgen, T. L., and Schmitt, J.
- Subjects
ddc:610 - Abstract
Background A two-fold risk increase to develop basal cell carcinoma was seen in outdoor workers exposed to high solar UV radiation compared to controls. However, there is an ongoing discussion whether histopathological subtype, tumor localization and Fitzpatrick phototype may influence the risk estimates. Objectives To evaluate the influence of histological subtype, tumor localization and Fitzpatrick phototype on the risk to develop basal cell carcinoma in highly UV-exposed cases and controls compared to those with moderate or low solar UV exposure. Methods Six hundred forty-three participants suffering from incident basal cell carcinoma in commonly sun-exposed anatomic sites (capillitium, face, lip, neck, dorsum of the hands, forearms outside, décolleté) of a population-based, case-control, multicenter study performed from 2013 to 2015 in Germany were matched to controls without skin cancer. Multivariate logistic regression analysis was conducted stratified for histological subtype, phototype 1/2 and 3/4. Dose-response curves adjusted for age, age2, sex, phototype and non-occupational UV exposure were calculated. Results Participants with high versus no (OR 2.08; 95% CI 1.24–3.50; p = 0.006) or versus moderate (OR 2.05; 95% CI 1.15–3.65; p = 0.015) occupational UV exposure showed a more than two-fold significantly increased risk to develop BCC in commonly UV-exposed body sites. Multivariate regression analysis did not show an influence of phototype or histological subtype on risk estimates. The restriction of the analysis to BCC cases in commonly sun-exposed body sites did not influence the risk estimates. The occupational UV dosage leading to a 2-fold increased basal cell carcinoma risk was 6126 standard erythema doses. Conclusion The risk to develop basal cell carcinoma in highly occupationally UV-exposed skin was doubled consistently, independent of histological subtype, tumor localization and Fitzpatrick phototype.
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- 2020
119. Predictive geometallurgical modelling
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Bachmann, K.
- Abstract
The modern mining industry faces a number of important technical challenges, such as declining ore grades, complex mineral associations, fine-grain size and increasing geological variability. To meet these challenges geometallurgical models are constructed to quantita-tively predict how ores will behave during extraction and beneficiation. Current geometal-lurgical programs carried out by industry, focus on the definition of larger spatial domains that have similar characteristics. However, a consequent application and further develop-ment of geometallurgical programs should lead to an implementation of spatially more highly resolved geometallurgical resource models that are truly predictive for each mined block (including uncertainty), in order to improve raw material quality control and the process efficiency of mining operations. Such an approach would also enable the targeted recovery of by-products, which may generate significant additional revenue and improve overall efficiency. In order to construct relevant resource models, detailed quantitative information on the spatial distribution and geometallurgical behaviour of the by-products within the deposit is crucial. The aim of this thesis is the development and creation of a predictive geometallurgical model by means of a case study and the presentation of the resulting advantages for the extraction of ores. Based on this, a general structure for the development of predictive geo-metallurgical models is developed, which can be applied to different types of commodities, as well as by-products, is cost-efficient, able to adapt to future data, and predicts metallurgi-cal parameters. As the case study serves the Thaba Chromium Mine in the western Bushveld Complex (South Africa), which is operated by Cronimet Chrome Mining SA (Pty) Ltd. In par-ticular, this thesis focusses on four distinct chromitite seams of the Lower and Middle Groups (LG and MG) at Thaba Mine, namely the LG-6, LG-6A, MG-1 and MG-2, which are considered as target seams for an open-cast and future underground mining scenario. In order to understand the geological and geochemical architecture of the Thaba Mine deposit and as a foundation of the predictive geometallurgical model, an extensive geo-chemical dataset as well as logging and drill core data provided by Cronimet was evaluated and a 3D geological model was developed. A statistical assessment was performed to evalu-ate the variability within and between the chromitite seams and to separate the mine lease area into distinct geochemical clusters. The distribution of the samples belonging to the dif-ferent geochemical clusters was then transposed onto the geology of the mine lease area. This allowed the definition of spatial domains. These spatial domains, recognized by the as-sessment of assay data only, are then validated by mineralogical attributes; implications for mineral beneficiation are tested and verified. According to this assessment, the chromitites of the Thaba Mine area can be subdivided into three distinct geochemical domains, domains that constitute the suitable foundation for a geometallurgical model. An extensive supergene altered domain or weathered domain is distinguished from a domain affected by hydrothermal alteration. The latter domain occurs below the depth of modern weathering, but in obvious proximity to faults and around a prominent dunite pipe. The third domain is represented by ores least affected by post-magmatic alteration processes. This domain occupies the centre of fault blocks below the extent of modern weathering. Furthermore, the geochemical data is used to develop a tailored and easy-to-use multi-variate classification scheme for the chromitite layers in the Thaba Mine, based on a com-prehensive classification routine for the LG and MG chromitites. This routine allows a clear attribution with known uncertainty of all relevant chromitite layers. It comprises of a hierar-chical discrimination approach relying on linear discriminant analysis and involves five dis-tinct steps. Overall classification results for unknown samples belonging to one of the layers are 81 %. The approach may, however, be extended across the entire Bushveld, provided that an appropriate geochemical data set is available. For detailed characterization of the mineral assemblages in the chromitite ores, selected core samples of the target layers were analysed in detail by various analytical methods, such as Mineral Liberation Analysis and Electron Probe Microanalysis. Therefore, we extended the common measurement protocols for electron probe microanalysis to ensure applicability to a wider range of PGM compositions and its overall accuracy as well as consistency. Based on the results two distinct major mineral assemblages are defined: The first assemblage is rich in platinum group element-sulphides, along with variable proportions of malanite/ cu-prorhodsite and alloys of Fe and Sn. The associated base metal sulphides are dominated by chalcopyrite and pentlandite, along with pyrite and subordinate millerite/ violarite. Associ-ated silicates are mainly primary magmatic orthopyroxene and plagioclase. The second as-semblage is rich in platinum group element-sulpharsenides and -arsenides as well as -antimonides and -bismuthides, which are associated with a base metal sulphide assemblage dominated by pentlandite and Co-rich pentlandite. The assemblage is also marked by an abundance of alteration minerals, such as talc, serpentine and/or carbonates, which are closely associated with the platinum group minerals. Statistical evaluation reveals that these two mineral assemblages cannot be attributed to their derivation from different chromitite layers, but document the effects of pervasive hydrothermal alteration. The knowledge of the detailed mineralogical investigation was transferred to a large da-taset comprising similar mineralogical data for unweathered ore of the deposit. Hence, it was possible to identify seven distinct ore types via statistical assessment, subsequently val-idated through beneficiation tests of drill core material. In addition, metallurgical test work for large batch samples of the weathered domain was carried out. Furthermore, beneficia-tion tests were aligned with process chemistry and mineralogy to monitor the results. The predictive geometallurgical model aims to express the recoverability of PGE as by-product from the chromite processing stream. Within this context, the weathered ores were regarded as a single domain, as chromite ores from this oxidized zone were consistently found to have very low PGE recoveries. Any attempt to recover PGE by flotation from this zone appears to be challenging. For unweathered ores, the approach towards a predictive geometallurgical model needs to be somewhat more complex. The following steps were performed: (i) Building a predictive model of the recoverability of PGE as a function of chemical composition, i.e. establish a chemical proxy for PGE recoverability; (ii) Performing a geostatistical modelling of the geochemical dataset, i.e. interpolation through cokriging, and (iii) Combining step (i) and (ii) to generate a spatially-resolved geometallurgical model able to predict the potential to recover PGE by flotation in terms of probabilities. The resultant predictive, spatially-resolved geometallurgical model displays the PGE pro-cessing potential in terms of probabilities and therefore incorporates uncertainty. Based on the work flow applied in this study, a more generic framework towards a predictive geometallurgical model can be proposed that can be applied to different commodities, is able to adapt to future data, and predicts metallurgical parameters, e.g. the recoverability of an ore as probabilities (and therefore including uncertainty). Furthermore, the model can be applied to main as well as by-product and therefore represents a holistic modelling approach. Most of the modelled parameters are derived from primary ore properties (e.g. rock or particle stream), e.g. modal mineralogy, mineral association, densities, etc., combined with a minimum of empirical test work.
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- 2020
120. Charakterisierung von Lithium-Ionen-Batterien (LIB) in Recyclingprozessen und Abschätzung der Aufschlusseffizienz von Elektroden mithilfe automatisierter Mineralogie
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Bachmann, K., Vanderbruggen, A., Hayagan, N. L., and Rudolph, M.
- Abstract
Lithium-Ionen-Batterien (LIBs) gehören zu den derzeit wichtigsten elektrochemischen Energiespeichersystemen für elektronische Mobilgeräte und Elektrofahrzeuge. Die wachsende weltweite Nachfrage nach LIBs, geht mit einer Erhöhung des Bedarfs an Co, Mn, Ni, Li und Graphit einher. Diese Erhöhung der Nachfrage dieser Rohstoffe stellt eine besondere Herausforderung für den schon jetzt angespannten weltweiten Rohstoffmarkt dar, verbunden mit Versorgungsrisiken, Preisschwankungen und Marktmonopolen. Tatsächlich sind Co und natürlicher Graphit in Europa seit 2010 als kritische Rohstoffe (CRM) geführt, Li sowie Mn befinden sich an der Grenze der Kritikalität. Um potenziell die Kluft zwischen Angebot und Nachfrage zu verringern sowie die europäischen Nachhaltigkeitsziele zu erreichen, hat das Recycling von Lithium-Ionen-Batterien (LIB) hat in den letzten Jahren viel Aufmerksamkeit auf sich gezogen. Hierbei wird sich hauptsächlich auf die wertvollen Metalle wie Kobalt, Nickel und Lithium konzentriert. Allerdings gehen während des Recyclingprozesses erhebliche Mengen anderer Komponenten wie Elektrolyt, Separator oder Graphit verloren. So kann Graphit zum Beispiel während der pyrometallurgischen Behandlung entweder abgeschlackt oder als Reduktionsmittel verbraucht werden. Darüber hinaus gehen einige andere wertvolle Metalle wie Co in den Grobfraktionen durch einen zu geringen Aufschlussgrad an die Berge verloren. Aus diesem Grund müssen neue und umfassende LIB-Recyclingverfahren gefunden werden. In dieser Studie werden zur Freisetzung von aktiven Materialien aus Elektroden sowohl eine mechanische als auch thermo-mechanische Recyclingprozessroute angewendet. Dabei wird neben den werthaltigen Metallen insbesondere die Rückgewinnung von Graphit in den Fokus gestellt. Die mechanische Route arbeitet mit einem Schlagscherbrecher, während für die thermo-mechanischen Versuche die Batterien vor dem Zerkleinern bei 500-650 °C vakuumpyrolysiert wurden. Die sogenannte Schwarzmasse-Fraktion kleiner als 1 mm wurde abgetrennt und basierend auf der Partikelgrößenverteilung in 4 Größenfraktionen klassifiziert. Eine genaue Charakterisierung sowohl der Hauptchemie als auch eine detaillierte Charakterisierung der enthaltenen Phasen im recycelten Materials stellt nach wie vor eine große Herausforderung dar. Deshalb wurde jede Fraktion wurde durch verschiedene analytische Methoden charakterisiert, einschließlich Röntgenfluoreszenz (XRF), Röntgenbeugung (XRD), Atomabsorptionsspektrometrie (AAS). Für eine gute Visualisierung und Quantifizierung der Ergebnisse des Aufbereitungserfolgs und Prozesseffizienz ist eine detailliertere analytische Charakterisierung erforderlich. Diese Studie schlägt eine innovative und neuartige neue Charakterisierungsmethode vor, die auf automatisierter Mineralogie basiert. Dabei werden verschiedene wichtige Partikelparameter wie Größe, Zusammensetzung und Verwachsung analysiert und quantitativ ausgewertet. Das für die Messungen genutzte Mineral Liberation Analyzer (MLA) System nutzt eine Kombination aus Rasterelektronenmikroskopie (REM) -Bildanalyse und energie-dispersiver Röntgenspektroskopie (EDS) und ist im primären Rohstoffsektor als leistungsstarke Methode etabliert. Allerdings fehlen für den Einsatz im sekundären Rohstoffsektor dezidierte Datenbanken, um die Partikel der Schwarzmasse schnell und präzise analysieren zu können. Eine analytische Herausforderung dieser Studie ist es demnach auch eine Datenbank zur Batteriecharakterisierung zu erstellen und für breite Anwendungsbereiche einsetzen zu können. Im Ergebnis zeigt die hier vorgestellte Studie, dass bei den angewendeten Zerkleinerungsverfahren eine Freisetzungsselektivität der Elektrodenfolien beobachtet werden konnte. Der thermo-mechanische Prozess setzt dabei mehr aktive Partikel aus den Folien frei als ein mechanischer Prozess allein. Infolgedessen sind insbesondere bei thermo-mechanisch zerkleinerten Proben die meisten Graphitpartikel in der
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- 2020
121. R as an environment for data mining of process mineralogy data: A case study of an industrial rougher flotation bank
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(0000-0002-5051-3395) Kupka, N., (0000-0001-9847-0462) Tolosana Delgado, R., Schach, E., (0000-0001-8904-6555) Bachmann, K., Heinig, T., (0000-0002-5374-6135) Rudolph, M., (0000-0002-5051-3395) Kupka, N., (0000-0001-9847-0462) Tolosana Delgado, R., Schach, E., (0000-0001-8904-6555) Bachmann, K., Heinig, T., and (0000-0002-5374-6135) Rudolph, M.
- Abstract
Through a series of in-house routines of R, an open source programming language for statistical computing, statistical analysis is applied to automated process mineralogy data in order to describe the performance of an industrial scheelite rougher flotation bank. These routines allow: 1) exploring all particles properties over residence time, not only particle size or surface liberation but also mineral association and a wealth of other particle properties, 2) to free the user from the limitations of the menu-driven built-in mineralogy software or spreadsheets, for calculation, data plotting or predictive model fitting, in particular for the parallel analysis of several streams; and 3) a more flexible manipulation of the data, both class and particle wise, for instance allowing for data mining across streams. In an illustration case study, these functions are used to show the separation efficiency shift over residence time and over particle size; to indicate which associated minerals have a greater influence on the flotation of scheelite; to determine which gangue minerals are more impacted by entrainment; and finally to link said entrainment to particle shape. In general, the Helmholtz Institute Freiberg for Resource Technology intends to use such a programming platform on automated mineralogy data as a routine to understand processes better, as a potential diagnostic tool for process troubleshooting, and also for predictive model building within the frame of geometallurgy.
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- 2020
122. We visualize value!
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(0000-0001-8904-6555) Bachmann, K. and (0000-0001-8904-6555) Bachmann, K.
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Dieser Beitrag stellt Erzlabor, ein Spin-Off des HZDR, den Transferassistenten aus Sachsen vor.
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- 2020
123. An open source platform for predictive geometallurgy
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(0000-0001-9847-0462) Tolosana Delgado, R., Schach, E., (0000-0002-5051-3395) Kupka, N., Buchmann, M., (0000-0001-8904-6555) Bachmann, K., (0000-0001-6625-559X) Frenzel, M., (0000-0001-8041-5406) Pereira, L., (0000-0002-5374-6135) Rudolph, M., (0000-0003-4646-943X) Boogaart, K. G., (0000-0001-9847-0462) Tolosana Delgado, R., Schach, E., (0000-0002-5051-3395) Kupka, N., Buchmann, M., (0000-0001-8904-6555) Bachmann, K., (0000-0001-6625-559X) Frenzel, M., (0000-0001-8041-5406) Pereira, L., (0000-0002-5374-6135) Rudolph, M., and (0000-0003-4646-943X) Boogaart, K. G.
- Abstract
Geometallurgy (the science of predicting the behaviour of ores along the value chain on the basis of their geoscientific characteristics) has barely moved beyond process mineralogy studies. These studies typically describe the mineralogical and microstructural characteristics of pristine or processed ores, for qualitative or semi-quantitative assessment of the processing performance and, eventually, a trial-and-error optimisation of the operation. But to deliver on its promise, geometallurgy should progress beyond this to provide fully quantitative models of such primary ore characteristics and the performance of their processing, both in average value and, most importantly, keeping track of their uncertainty. Only then it will be possible to optimise the operation in a predictive way. For this goal, we have developed a data mining platform consisting on a SQL database, an R front-end in-house package, and back-ends interpreting data from several analytical instruments into the database. A structured relational SQL database is useful to organise all available information (geometry, phase, chemistry, physical properties) of mineral grains, particles and samples. The R front-end allows to use the statistical and data mining power of this open-source environment in a transparent way for any geomet task, from ore characterisation to process fitting and forecasting, from geostatistical prediction to operational optimisation. With regard to the back-ends, currently we import XRD, XRF and mineral liberation analysis measurements, and we will incorporate other data sources. The scripting abilities of R allow to process many streams in loop freeing the user of repeating tedious click-and-drop tasks; compute virtually any quantity; distribute the work among several clusters; or keep a log file of the calculations done, for accountability. This contribution presents the building blocks of this package, and their use with several examples in geometallurgical tasks.
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- 2020
124. Charakterisierung von Lithium-Ionen-Batterien (LIB) in Recyclingprozessen und Abschätzung der Aufschlusseffizienz von Elektroden mithilfe automatisierter Mineralogie
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(0000-0001-8904-6555) Bachmann, K., (0000-0003-4092-4374) Vanderbruggen, A., Hayagan, N. L., (0000-0002-5374-6135) Rudolph, M., (0000-0001-8904-6555) Bachmann, K., (0000-0003-4092-4374) Vanderbruggen, A., Hayagan, N. L., and (0000-0002-5374-6135) Rudolph, M.
- Abstract
Lithium-Ionen-Batterien (LIBs) gehören zu den derzeit wichtigsten elektrochemischen Energiespeichersystemen für elektronische Mobilgeräte und Elektrofahrzeuge. Die wachsende weltweite Nachfrage nach LIBs, geht mit einer Erhöhung des Bedarfs an Co, Mn, Ni, Li und Graphit einher. Diese Erhöhung der Nachfrage dieser Rohstoffe stellt eine besondere Herausforderung für den schon jetzt angespannten weltweiten Rohstoffmarkt dar, verbunden mit Versorgungsrisiken, Preisschwankungen und Marktmonopolen. Tatsächlich sind Co und natürlicher Graphit in Europa seit 2010 als kritische Rohstoffe (CRM) geführt, Li sowie Mn befinden sich an der Grenze der Kritikalität. Um potenziell die Kluft zwischen Angebot und Nachfrage zu verringern sowie die europäischen Nachhaltigkeitsziele zu erreichen, hat das Recycling von Lithium-Ionen-Batterien (LIB) hat in den letzten Jahren viel Aufmerksamkeit auf sich gezogen. Hierbei wird sich hauptsächlich auf die wertvollen Metalle wie Kobalt, Nickel und Lithium konzentriert. Allerdings gehen während des Recyclingprozesses erhebliche Mengen anderer Komponenten wie Elektrolyt, Separator oder Graphit verloren. So kann Graphit zum Beispiel während der pyrometallurgischen Behandlung entweder abgeschlackt oder als Reduktionsmittel verbraucht werden. Darüber hinaus gehen einige andere wertvolle Metalle wie Co in den Grobfraktionen durch einen zu geringen Aufschlussgrad an die Berge verloren. Aus diesem Grund müssen neue und umfassende LIB-Recyclingverfahren gefunden werden. In dieser Studie werden zur Freisetzung von aktiven Materialien aus Elektroden sowohl eine mechanische als auch thermo-mechanische Recyclingprozessroute angewendet. Dabei wird neben den werthaltigen Metallen insbesondere die Rückgewinnung von Graphit in den Fokus gestellt. Die mechanische Route arbeitet mit einem Schlagscherbrecher, während für die thermo-mechanischen Versuche die Batterien vor dem Zerkleinern bei 500-650 °C vakuumpyrolysiert wurden. Die sogenannte Schwarzmasse-Fraktion
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- 2020
125. Modelling indium deportment in a polymetallic sulfide ore - The case of Neves-Corvo, Portugal
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Frenzel, M., Bachmann, K., Carvalho, J., Relvas, J., Pacheco, N., Gutzmer, J., Frenzel, M., Bachmann, K., Carvalho, J., Relvas, J., Pacheco, N., and Gutzmer, J.
- Abstract
There is a general lack of reliable quantitative data on the mineralogy and spatial distribution of indium and other by-product metals in ore deposits. This contribution showcases a new approach to integrate by-product metals into geometallurgical assessments. As an example, it uses the distribution and deportment of indium at Neves-Corvo, a major European base-metal mine (Cu + Zn). This study is the first to develop a quantitative model of indium deportment in volcanic hosted massive sulfide ores, demonstrating how regularities in indium partitioning between different minerals can be used to predict its mineralogical deportment in individual drill-core samples. Bulk-ore assays of As, Cu, Fe, Pb, S, Sb, Sn, Zn, and In are found to be sufficient for reasonably accurate predictions. The movement of indium through the ore processing plants is well explained by its mineralogical deportment, allowing for specific mine and process planning. The novel methodologies implemented in this contribution should be of general applicability to the geometallurgical assessment of many other byproduct metals in polymetallic sulfide ores, including Ga, Ge, Mo, Re, Se, Te, as well as the noble metals.
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- 2020
126. Geometallurgical Characterization of Tailing Storage Facilities
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(0000-0001-8904-6555) Bachmann, K. and (0000-0001-8904-6555) Bachmann, K.
- Abstract
This presentations shows novel analytical methods and geometallurgical modelling techniques for re-mining of tailing storage facilities.
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- 2020
127. Erzlabor - we visualize value!
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(0000-0001-8904-6555) Bachmann, K. and (0000-0001-8904-6555) Bachmann, K.
- Abstract
Dieser Beitrag stellt Erzlabor, ein Spin-Off des HZDR, den Partnern des EIT RawMaterials in Europa vor.
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- 2020
128. Vom Erz zum Metall – Innovative Materialcharakterisierung durch Automatisierte Mineralogie
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(0000-0001-8904-6555) Bachmann, K. and (0000-0001-8904-6555) Bachmann, K.
- Abstract
‚Automatisierte Mineralogie‘ bezeichnet eine analytische Untersuchungsmethode auf Basis einer Kombination von Rasterelektronenmikroskopie (REM) und energiedispersiver Röntgenspektroskopie (EDS). Automatisierte mineralogische Untersuchungen bieten die einzigartige Möglichkeit quantitative Daten einer Vielzahl von Parametern aufzustellen, die für die Entwicklung und kritische Bewertung von Aufbereitungstests greifbar sind. Diese Parameter umfassen den modalen Mineralbestand, den kalkulierten Elementgehalt, Elementverteilungen, Mineralassoziationen, Größenverteilungen von Partikeln und Mineralkörnern, Partikeldichteverteilungen sowie die Mineralfreisetzung. Aus den Analysedaten können auch Proben-Übersichtsbilder (‚Mineralkarten‘) und Bilder bestimmter Mineralgruppen extrahiert werden. Die Möglichkeiten werden anhand von zwei Beispielen verdeutlicht. Zum Einen wurde sogenannte Schwarzmasse charakterisiert, ein sekundärer Rohstoff, welche beim Recycling von Li-Ionenbatterien entsteht. Zum Anderen, geht es um primäre Lagerstätten, hier die Gewinnung von Platingruppenelementen in einer Chromitlagerstätte in Südafrika.
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- 2020
129. Prädiktive Geometallurgie in Freiberg – von „Virtual Twins“ und Prozessoptimierung
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(0000-0001-8904-6555) Bachmann, K., (0000-0001-8041-5406) Pereira, L., (0000-0001-9847-0462) Tolosana Delgado, R., (0000-0003-4646-943X) Boogaart, K. G., (0000-0002-1034-6545) Gutzmer, J., (0000-0001-8904-6555) Bachmann, K., (0000-0001-8041-5406) Pereira, L., (0000-0001-9847-0462) Tolosana Delgado, R., (0000-0003-4646-943X) Boogaart, K. G., and (0000-0002-1034-6545) Gutzmer, J.
- Abstract
Der moderne Bergbausektor steht vor gewaltigen technischen Herausforderungen. Dazu zählen der Rückgang von Erzgehalten, der zunehmende Umgang mit komplexen Mineralparagenesen und sehr feinen Korngrößen aber auch einer steigenden Erzvariabilität. Mit Hilfe geometallurgischer Modelle versucht die Bergbauindustrie diese Herausforderungen zu bewältigen und das Verhalten des Erzes während des Abbaus, der Aufbereitung und der Verhüttung quantitativ vorherzusagen. Um hier einen Beitrag zu leisten, wird am Standort Freiberg seit 2008 geometallurgische Kernkompetenz aufgebaut. Diese Entwicklung wurde mit der Gründung des Helmholtz-Instituts Freiberg für Ressourcentechnologie (HIF), einer gemeinsamen Gründung des Helmholtz-Zentrums Dresden-Rossendorf (HZDR) und der TU Bergakademie Freiberg (TU Bergakademie Freiberg) im Jahr 2011, stark beschleunigt. Aus diesem Grund zählt Freiberg heute weltweit zu den wichtigsten Forschungs- und Entwicklungsstandorten der Geometallurgie. In diesem Artikel werfen wir einen Blick auf den aktuellen Stand der Entwicklungen, mit Fokus auf zwei sehr erfolgreiche Projekte im Bereich der geometallurgischen Modellierung, sowohl primärer als auch sekundärer Rohstoffe.
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- 2020
130. Predictive geometallurgical modelling
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(0000-0001-8904-6555) Bachmann, K. and (0000-0001-8904-6555) Bachmann, K.
- Abstract
The modern mining industry faces a number of important technical challenges, such as declining ore grades, complex mineral associations, fine-grain size and increasing geological variability. To meet these challenges geometallurgical models are constructed to quantita-tively predict how ores will behave during extraction and beneficiation. Current geometal-lurgical programs carried out by industry, focus on the definition of larger spatial domains that have similar characteristics. However, a consequent application and further develop-ment of geometallurgical programs should lead to an implementation of spatially more highly resolved geometallurgical resource models that are truly predictive for each mined block (including uncertainty), in order to improve raw material quality control and the process efficiency of mining operations. Such an approach would also enable the targeted recovery of by-products, which may generate significant additional revenue and improve overall efficiency. In order to construct relevant resource models, detailed quantitative information on the spatial distribution and geometallurgical behaviour of the by-products within the deposit is crucial. The aim of this thesis is the development and creation of a predictive geometallurgical model by means of a case study and the presentation of the resulting advantages for the extraction of ores. Based on this, a general structure for the development of predictive geo-metallurgical models is developed, which can be applied to different types of commodities, as well as by-products, is cost-efficient, able to adapt to future data, and predicts metallurgi-cal parameters. As the case study serves the Thaba Chromium Mine in the western Bushveld Complex (South Africa), which is operated by Cronimet Chrome Mining SA (Pty) Ltd. In par-ticular, this thesis focusses on four distinct chromitite seams of the Lower and Middle Groups (LG and MG) at Thaba Mine, namely the LG-6, LG-6A, MG-1 and MG-2, which are con
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- 2020
131. Characterization of lithium ion battery recycling processes and estimation of liberation efficiency of electrodes using automated mineralogy
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(0000-0003-4092-4374) Vanderbruggen, A., Hayagan, N. L., (0000-0001-8904-6555) Bachmann, K., (0000-0002-5374-6135) Rudolph, M., (0000-0003-4092-4374) Vanderbruggen, A., Hayagan, N. L., (0000-0001-8904-6555) Bachmann, K., and (0000-0002-5374-6135) Rudolph, M.
- Abstract
Lithium-ion batteries (LIBs) are currently one of the most important electrochemical energy storage devices, powering electronic mobile devices and electric vehicles. Growing global demands for Co, Mn, Ni, Li, and graphite which are all used and present in LIBs as energy storage added difficulties to the already deficit and imbalance supply of sources of raw materials worldwide, which resulted to supply risks, price fluctuations and monopoly of market. In fact, Co and natural graphite are listed as critical raw materials (CRMs) in Europe since 2010 and Mn, and Li are on the boundary of criticality. While recycling is identified as a solution to potentially reduce the gap between the demand and supply. Recycling of lithium ion battery (LIB) has attracted a lot of attention in the recent years and focuses primarily on valuable metals such as cobalt, nickel and lithium. During the recycling processes, considerable amount of the components are lost like electrolyte, separator or graphite. For instance, graphite can either be slagged-off or consumed as a reductant agent during pyrometallurgical treatment. Some other loses are due to a lack of liberation of the targeted particles, elements such as Co are lost in the coarse fractions and a not recovered in the right product. Hence, there is a need to find innovative and comprehensive LIB recycling operations. For understanding and be able to quantify the loses and recycling process efficiency a deeper characterization is required. This research proposes a new characterization method based on automated mineralogy. In this study, the particles morphologies (size, composition and phases associations) are analysed. The liberation of active materials from electrodes is quantified by comparing two recycling processes: mechanical and thermochemical-mechanical. The mechanical route operates with an impact shear crusher while for the thermomechanical operation the batteries were vacuum pyrolyzed at 500-650oC before to be crushed. T
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- 2020
132. Examining morphological and molecular diagnostic character states of Cichorium intybus L. (Asteraceae) and C. spinosum L.
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Gemeinholzer, B. and Bachmann, K.
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- 2005
- Full Text
- View/download PDF
133. QTL mapping reveals a two-step model for the evolutionary reduction of inner microsporangia within the asteracean genus Microseris
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Gailing, O. and Bachmann, K.
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- 2003
- Full Text
- View/download PDF
134. Diabetische Retinopathie: Kontraktilität retinaler Arteriolen unter Sauerstoffatmung
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Blum, M., Vollrath, D., Bartke, T., Bachmann, K., and Strobel, J.
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- 2003
- Full Text
- View/download PDF
135. Nanoscale GaN whiskers fabricated by photoelectrochemical etching
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Grenko, J.A., Reynolds, C.L. Jr., Schlesser, R., Hren, J.J., Bachmann, K., Sitar, Z., and Kotula, P.G.
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Sapphires -- Chemical properties ,Electrolytes -- Chemical properties ,Gallium nitrate -- Chemical properties ,Etching -- Analysis ,Physics - Abstract
GaN whiskers with nanoscale dimensions are fabricated by photoelectrochemical (PEC) etching in dilute H(sub 3)PO(sub 4) electrolyte. The presence of a dislocation along the central axis of the needles is clearly demonstrated, and the etch pattern is suggested to be related to the growth mechanism for GaN on sapphire.
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- 2004
136. AFLP diversity in the common vetch (Vicia sativa L.) on the world scale
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Potokina, E., Blattner, F., Alexandrova, T., and Bachmann, K.
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- 2002
- Full Text
- View/download PDF
137. Alterskorrelierte Kontraktilität retinaler Arteriolen bei Sauerstoffatmung
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Blum, M., Scherf, C., Bachmann, K., and Strobel, J.
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- 2001
- Full Text
- View/download PDF
138. Onion microsatellites for germplasm analysis and their use in assessing intra- and interspecific relatedness within the subgenus Rhizirideum
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Fischer, D. and Bachmann, K.
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- 2000
- Full Text
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139. NUCLEAR DNA AND DEVELOPMENTAL RATE IN FROGS
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Bachmann, K and BioStor
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- 1972
140. Modeling and Real-Time Process Monitoring of Organometallic Chemical Vapor Deposition of III-V Phosphides and Nitrides at Low and High Pressures
- Author
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Bachmann, K. J., Cardelino, B. H., Moore, C. E., Cardelino, C. A., Sukidi, N., and Mccall, S.
- Published
- 1999
- Full Text
- View/download PDF
141. Gehörschäden durch Freizeitlärm
- Author
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Zenner, H. P., Struwe, V., Schuschke, G., Spreng, M., Stange, G., Plath, P., Babisch, W., Rebentisch, E., Plinkert, P., Bachmann, K. D., Ising, H., and Lehnert, G.
- Published
- 1999
- Full Text
- View/download PDF
142. Impact of tricuspid valve regurgitation severity and its secondary reduction on long-term survival after transcatheter mitral valve edge-to-edge repair
- Author
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Geyer, M, primary, Keller, K, additional, Ruf, T, additional, Kreidel, F, additional, Petrescu, A, additional, Tamm, A.R, additional, Born, S, additional, Bachmann, K, additional, Hahad, O, additional, Beiras-Fernandez, A, additional, Kornberger, A, additional, Schulz, E, additional, Munzel, T, additional, and Von Bardeleben, R.S, additional
- Published
- 2020
- Full Text
- View/download PDF
143. Characterization of lithium ion battery recycling processes and estimation of liberation efficiency of electrodes using automated mineralogy
- Author
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Vanderbruggen, A., primary, Hayagan, N., additional, Bachmann, K., additional, and Rudolph, M., additional
- Published
- 2020
- Full Text
- View/download PDF
144. Rock Pop Jazz
- Author
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Bachmann, K. R., primary, Brügmann, N., additional, Eickmann, J., additional, Falk, M., additional, Franzen, S., additional, Helms, S., additional, Herbstmeier, M., additional, Hoffmann, C., additional, Kleinelanghorst, A., additional, Kurth, U., additional, Lörscher, H., additional, Lübker-Suhre, G., additional, Noltensmeier, R., additional, Schomberg, C., additional, Scheel, I., additional, Simon, R.-M., additional, and Simon, S., additional
- Published
- 2006
- Full Text
- View/download PDF
145. Antibradykarde Ventrikelstimulation während der vulnerablen Phase des Herzzyklus bei ICD-System mit DDD-Herzschrittmacherfunktion
- Author
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Schibgilla, V., Nossen, J., Kuhn, I., and Bachmann, K.
- Published
- 1998
- Full Text
- View/download PDF
146. Möglichkeiten und Grenzen der Elektronenstrahltomographie
- Author
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Moshage, W., Achenbach, S., and Bachmann, K.
- Published
- 1998
- Full Text
- View/download PDF
147. AV-Synchronizität und Frequenzadaptation: Einflüsse auf die Sauerstoffkinetik von Schrittmacherpatienten während submaximaler Belastung
- Author
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Schibgilla, V., Proschek, T., Kuhn, I., MacCarter, D., and Bachmann, K.
- Published
- 1998
- Full Text
- View/download PDF
148. Beurteilung von Koronararterienstenosen mittels atemkontrollierter NMR-Angiographie
- Author
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Kessler, W., Achenbach, S., Moshage, W., Zink, D., Ropers, D., Kroeker, R., Nitz, W., Laub, G., and Bachmann, K.
- Published
- 1998
- Full Text
- View/download PDF
149. Pränatale Registrierung fetaler Herzaktionen mit Magnetokardiographie
- Author
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Menéndez, T., Achenbach, S., Moshage, W., Flüg, M., Beinder, E., Kollert, A., Bittel, A., and Bachmann, K.
- Published
- 1998
- Full Text
- View/download PDF
150. Growth of NLO Chalcopyrite Materials by Omvpe
- Author
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Timmons, M. L. and Bachmann, K. J.
- Published
- 1997
- Full Text
- View/download PDF
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