TY - JOUR A1 - Smol, M. A1 - Adam, Christian A1 - Krüger, O. T1 - Use of nutrients from wastewater for the fertilizer industry - approaches towards the implementation of the circular economy (CE) N2 - More sustainable waste management practices are an important element in the Transformation towards a circular economy (CE). Activities in this area should be dedicated to all groups of waste, including those generated in the water and sewage sector. This paper presents the characteristics of sewage sludge ash (SSA) coming from Polish municipal waste incineration plants. Due to the high content of nutrients such as phosphorus (8.01% P2O5), calcium (5.11% CaO) and magnesium (2.75% MgO), the analyzed SSA may constitute a valuable source of raw materials for the fertilizer industry. Despite the good fertilizing properties of the SSA, in some cases the presence of heavy metals such as cadmium (0.74–1.4 mg/kg dry matter), lead (49.8–99 mg/kg dry matter), mercury (3.93 mg/kg dry matter) and arsenic (4.23–4.43 mg/kg dry matter) and poor bioavailability of P from SSA disqualifies this waste from direct use as a fertilizer. Therefore, it is necessary to look for methods that will allow the municipal SSA to be processed, for example, technologies for the extraction of phosphorus and the production of phosphate fertilizer. This way of SSA management is in the line with the CE assumptions, in which waste becomes a valuable source of secondary raw materials. Fertilizer produced from waste meeting quality, safety and labelling requirements and limits of organic, microbiological and physical contaminants will be able to be traded freely within the European Union (EU) and receive the CE marking. The idea of use of SSA for fertilizer purposes is consistent not only with the objectives of the CE but also with the Polish National Waste Management Plan 2022 and the Municipal Sewage Sludge Strategy 2019–2022, which emphasizes the necessity to maximize the use of biogenic substances contained in wastewater. Therefore, sustainable management of SSA, in particular its storage in a way enabling the recovery of phosphorus, should be promoted. KW - Wastewater KW - Circular economy KW - Fertilizer KW - Sewage sludge KW - Phosphorus PY - 2020 DO - https://doi.org/10.5004/dwt.2020.25113 VL - 1 SP - 1 EP - 9 PB - Desalination Publications CY - Hopkinton, MA 01748, USA AN - OPUS4-50646 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Taube, Mareike Carolin A1 - Adam, Christian A1 - Adamczyk, Burkart A1 - Beckmann, T. A1 - Reuter, M. A1 - Stelter, M. ED - Reiser, B. T1 - Recycling von metallurgischen Rückständen - Schmelzversuche zeigen, wie die Tantalrückgewinnung aus Zinnschlacken und weiteren Reststoffen optimiert werden kann N2 - Since the recycling of tantalum bearing post-consumer waste is practically not existent, metallurgical residues are the most important feed for the tantalum recycling. Most tin ores naturally contain significant quantities of refractory metals. During the smelting process in primary tin production these elements are enriched in the slag phase. This slag is a highly valuable raw material for tantalum production due to its considerable concentration of tantalum and its functioning as an additional slag former in further pyrometallurgical treatment. In this paper the first process stage of an existing pyrometallurgical process for tantalum recovery, mainly from low grade pyrometallurgical residues, is discussed. Smelting trials were carried out in a pilot-scale electric arc furnace to analyse the effect of feeding on the activity of carbon as a reducing agent. Therefore, blowing petroleum coke through an iron lance and the manual adding of coke into the melting bath were tested. During the pyrometallurgical treatment elements with a high affinity to carbon were reduced to their carbide form and enriched in the molten iron-based metal phase. The objective of the process was to reduce the oxidic tantalum completely and to enrich it into the metal phase. Furthermore, the transfer of unwanted elements such as titanium into the metal phase was aimed to be avoided. Spoon test specimens were taken from the liquid mineral melt to follow the evolution of the reduction process. The cooled down solidified melting bath was investigated by using the XRD and EDX method to characterise the slag system and to identify relevant mineral phases. N2 - Da das Recycling von tantalhaltigen Post-Consumer-Abfällen praktisch nicht existiert, stellen metallurgische Reststoffe eine äußerst wichtige Rohstoffquelle für das Tantalrecycling dar. Die meisten Zinnerze enthalten von Natur aus erhebliche Mengen an Refraktärmetallen. Diese Elemente werden in den Schlacken der pyrometallurgischen Primärzinngewinnung angereichert. Aufgrund ihrer vergleichsweise hohen Wertstoffkonzentration und ihrer Funktion als zusätzlicher Schlackenbildner stellen diese Schlacken einen wertvollen Rohstoff für die Verhüttung tantalhaltiger Reststoffe dar. In der vorliegenden Arbeit wird ein existierendes Verfahren zur Tantalrückgewinnung diskutiert, dem hauptsächlich pyrometallurgische Rückstände geringer Wertstoffkonzentration als Einsatzstoff dienen. Mit Hilfe des Verfahrens sollte dasoxidisch vorliegende Tantal vollständig reduziert und in der Metallphase angereichert werden. Weiterhin sollte vermieden werden, dass unerwünschte Elemente wie Titan in die Metallphase überführt werden. Ziel der Untersuchung war es, die ablaufenden Reduktionsprozesse besser zu verstehen, um so Ansätze für die Prozessoptimierung identifizieren zu können. KW - Lichtbogenofen KW - Pyrometallurgie KW - Recycling KW - Tantal KW - Zinnschlacke PY - 2020 SN - 0934-3482 VL - 33 SP - 10 EP - 17 PB - Rhombos-Verlag CY - Berlin AN - OPUS4-50656 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Smol, M. A1 - Adam, Christian A1 - Preisner, M. T1 - Circular economy model framework in the European water and wastewater sector N2 - One of the key elements in the transformation towards a circular economy (CE) is providing more sustainable practices for resources and waste management. Improvement actions focused on transformation towards a CE should be targeted at all groups of materials and waste. As water is essential for human survival and well-being and plays a significant role in sustainable development (SD), the actions related to the reuse of water and the recovery of raw materials from wastewater and other water-based waste should be taken. The paper presents a proposition for a new CE model framework in the water and wastewater sector, which includes the six following actions: reduction—prevent wastewater generation in the first place by the reduction of water usage and pollution reduction at source; reclamation (removal)—an application of effective Technologies for the removal of pollutants from water and wastewater; reuse—reuse of wastewater as an alternative source of water supply (non-potable usage), recycling—recovery of water from wastewater for potable usage; recovery—recovery of resources such as nutrients and energy from water-based waste, and rethink—rethinking how to use resources to create a sustainable economy, which is `free` of waste and emissions. The novelty of the proposed CE model framework is that it presents possible ways of implementing CE principles in the water and wastewater sector, with a strong emphasis not only technological but also organisational and societal changes. Application of the proposed model may help to further transform the European economy to the CE model. Moreover, the indicated model can be significant tool supporting an assessment of local or regional progress towards CE in the water and wastewater sector and further environmental management and planning. KW - Circular economy KW - Phosphorus recovery KW - Waste water PY - 2020 DO - https://doi.org/10.1007/s10163-019-00960-z SP - 1 EP - 16 PB - Springer AN - OPUS4-50441 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Adamczyk, Burkart A1 - Neuhold, S. A1 - Drissen, P. A1 - Algermissen, D. A1 - Presoly, P. A1 - Sedlazeck, K. P. A1 - Schenk, J. A1 - Raith, J. G. A1 - Pomberger, R. A1 - Vollprecht, D. T1 - Tailoring the FeO/SiO2 ratio in electric arc furnace slags to minimize the leaching of Vanadium and Chromium N2 - Based on recently published research on leaching control mechanisms in electric arc furnace (EAF) slags, it is assumed that a FeO/SiO2 ratio of around one leads to low leached V and Cr concentrations. This ratio influences the mineral phase composition of the slag toward higher amounts of spinel and a lower solubility of calcium silicate phases by suppressing the formation of magnesiowuestite and highly soluble calcium silicate phases. To evaluate this hypothesis, laboratory and scaled up tests in an EAF pilot plant were performed on slag samples characterized by elevated V and Cr leaching and a high FeO/SiO2 ratio. Prior to the melting experiments, the optimum FeO/SiO2 ratio was calculated via FactSageTM. In the melting experiments, the ratio was adjusted by adding quartz sand, which also decreased the basicity (CaO/SiO2) of the slag. As a reference, remelting experiments without quartz sand addition were conducted and additionally, the influence of the cooling rate of the slag was examined. The remelted (without quartz sand) and the remelted modified slags (with quartz sand) were analyzed chemically and mineralogically and the leaching behavior was investigated. The modification of the slags yielded a minimized release of V and Cr, supporting the hypothesis that the FeO/SiO2 ratio influences the mineralogy and the leaching behavior. KW - Electric arc furnace slags KW - FactSage calculations KW - EAF slags KW - Leaching control mechanisms KW - Melting experiments PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-507748 DO - https://doi.org/10.3390/app10072549 VL - 10 IS - 7 SP - 2549 EP - 2565 AN - OPUS4-50774 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Adam, Christian T1 - Phosphor: Von der Rückgewinnung zum Recycling N2 - Eine entscheidende Problematik nach Inkrafttreten der neuen Klärschlammverordnung ist, wie Phosphor nicht nur rückgewonnen, sondern in den Markt eingeschleust und letztlich auch in den Kreislauf zurückgeführt werden kann. Die Wege hierzu sind noch weitgehend ungeklärt. Die DWA-Arbeitsgruppe KEK- 1.1 hat aus diesem Grund einen Workshop durchgeführt, um rechtliche Anforderungen an Rezyklate, Aspekte der Rezyklatqualität und -beschaffenheit sowie den aktuellen Markt für Rezyklate zu diskutieren. Auf Basis dieses Workshops wurde ein Arbeitsbericht erstellt, der sich schwerpunktmäßig mit dem Einsatz von Rezyklaten zu Düngezwecken beschäftigt. Hierzu liegen bereits Erkenntnisse vor, und es sind bereits Praxisbeispiele in der Umsetzung. KW - Phosphor KW - Klärschlamm PY - 2018 DO - https://doi.org/10.3242/kae2018.08.005 SN - 1866-0029 VL - 65 IS - 8 SP - 710 EP - 717 PB - Gesellschaft zur Förderung der Abwassertechnik (GFA) CY - Hennef AN - OPUS4-45661 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Auer, G. A1 - Spanka, M. A1 - Hamann, Christopher A1 - Adam, Christian T1 - Thermal zinc extraction from steel mill dust N2 - Treatment and reusing of hazardous wastes have become significant issues of modern societies. Blast furnace sludge (BFS) and electric arc furnace dust (EAFD) are such typical wastes, because they usually contain high amounts of undesirable elements such as zinc (Zn) and lead (Pb). These elements can cause operational problems in reusing of BFS and EAFD. In this study, the Ferro Duo GmbH and the Federal Institute for Materials Research and Testing have investigated a novel approach for eliminating and/or recovering Zn and Pb from both wastes. Applied was a selective chlorination and volatilization of Zn and Pb as chlorides at temperatures between 500 °C and 1100 °C. Both product obtained, Zn and Pb in the form of ZnCl2 and PbCl2 and the purified solid mineral compound are attractive materials for further use. Hydrochloric acid and iron(II) chloride were used as chlorination agents. Exceptionally high Zn and Pb removal efficiencies of >99.5 % could be achieved with both chlorination agents, whereby iron(II) chloride exhibited better performance. KW - Blast furnace sludge KW - Chlorination KW - Electric arc furnace dust KW - Lead KW - Zinc KW - Thermochemical treatment PY - 2019 SN - 1613-2394 VL - 72 IS - 1 SP - 27 EP - 31 PB - GDMB Verlag GmbH CY - Clausthal-Zellerfeld AN - OPUS4-47288 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Singh, Amit Kumar A1 - Mishra, Biswajit A1 - Sinha, Om Prakash T1 - Reduction Kinetics of Fluxed Iron Ore Pellets Made of Coarse Iron Ore Particles N2 - The present work demonstrates a sustainable approach of using relatively coarser iron ore particles for ironmaking. The motivation is to reduce the energy consumption in the milling of the iron ore by utilizing coarser iron ore particles (+0.05 mm) and to select a suitable binder for improving pellet properties. Iron ore fines in the range of 0.05–0.25 mm was selected and classified into three size ranges. Fluxed iron ore pellets were prepared using lime as a binder for the basicity of 0, 1, and 2. Reduction of these pellets with a packed bed of coal fines was performed in the temperature range of 900–1200 °C for a duration of 30–120 min. The direct reduction kinetics of the iron ore pellets were studied by employing diffusion and chemical reaction control models to the experimental data. The results show that pellets made with coarser iron ore particles have improved reduction behavior and kinetics. The reduction reaction is found to be a mixed control. The activation energy for the reduction reaction varies from 44.3 to 74.76 kJ mol−1 as iron ore particle size decreases from 0.25 to 0.05 mm and basicity increases from 0 to 2. KW - Materials Chemistry KW - Metals and Alloys KW - Process Metallurgy KW - Iron making PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-598326 DO - https://doi.org/10.1002/srin.202300669 SN - 1611-3683 IS - 2300669 SP - 1 EP - 9 PB - Wiley VHC-Verlag AN - OPUS4-59832 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Jovičević-Klug, Matic A1 - Souza Filho, Isnaldi R. A1 - Springer, Hauke A1 - Adam, Christian A1 - Raabe, Dierk T1 - Green steel from red mud through climate-neutral hydrogen plasma reduction N2 - AbstractRed mud is the waste of bauxite refinement into alumina, the feedstock for aluminium production1. With about 180 million tonnes produced per year1, red mud has amassed to one of the largest environmentally hazardous waste products, with the staggering amount of 4 billion tonnes accumulated on a global scale1. Here we present how this red mud can be turned into valuable and sustainable feedstock for ironmaking using fossil-free hydrogen-plasma-based reduction, thus mitigating a part of the steel-related carbon dioxide emissions by making it available for the production of several hundred million tonnes of green steel. The process proceeds through rapid liquid-state reduction, chemical partitioning, as well as density-driven and viscosity-driven separation between metal and oxides. We show the underlying chemical reactions, pH-neutralization processes and phase transformations during this surprisingly simple and fast reduction method. The approach establishes a sustainable toxic-waste treatment from aluminium production through using red mud as feedstock to mitigate greenhouse gas emissions from steelmaking. KW - Multidisciplinary PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-594424 DO - https://doi.org/10.1038/s41586-023-06901-z SN - 0028-0836 VL - 625 IS - 7996 SP - 703 EP - 709 PB - Springer Science and Business Media LLC AN - OPUS4-59442 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Maulas, Kryzzyl M. A1 - Paredes, Charla S. A1 - Tabelin, Carlito Baltazar A1 - Jose, Mark Anthony A1 - Opiso, Einstine M. A1 - Arima, Takahiko A1 - Park, Ilhwan A1 - Mufalo, Walubita A1 - Ito, Mayumi A1 - Igarashi, Toshifumi A1 - Phengsaart, Theerayut A1 - Villas, Edrhea A1 - Dagondon, Sheila L. A1 - Metillo, Ephrime B. A1 - Uy, Mylene M. A1 - Manua, Al James A. A1 - Villacorte-Tabelin, Mylah T1 - Isolation and Characterization of Indigenous Ureolytic Bacteria from Mindanao, Philippines: Prospects for Microbially Induced Carbonate Precipitation (MICP) N2 - Microbially induced carbonate precipitation (MICP), a widespread phenomenon in nature, is gaining attention as a low-carbon alternative to ordinary Portland cement (OPC) in geotechnical engineering and the construction industry for sustainable development. In the Philippines, however, very few works have been conducted to isolate and identify indigenous, urease-producing (ureolytic) bacteria suitable for MICP. In this study, we isolated seven, ureolytic and potentially useful bacteria for MICP from marine sediments in Iligan City. DNA barcoding using 16s rDNA identified six of them as Pseudomonas stutzeri, Pseudomonas pseudoalcaligenes, Bacillus paralicheniformis, Bacillus altitudinis, Bacillus aryabhattai, and Stutzerimonas stutzeri but the seventh was not identified since it was a bacterial consortium. Bio-cementation assay experiments showed negligible precipitation in the control (without bacteria) at pH 7, 8, and 9. However, precipitates were formed in all seven bacterial isolates, especially between pH 7 and 8 (0.7–4 g). Among the six identified bacterial species, more extensive precipitation (2.3–4 g) and higher final pH were observed in S. stutzeri, and B. aryabhattai, which indicate better urease production and decomposition, higher CO2 generation, and more favorable CaCO3 formation. Characterization of the precipitates by scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDS) and attenuated total reflectance Fourier transform spectroscopy (ATR-FTIR) confirmed the formation of three carbonate minerals: calcite, aragonite, and vaterite. Based on these results, all six identified indigenous, ureolytic bacterial species from Iligan City are suitable for MICP provided that the pH is controlled between 7 and 8. To the best of our knowledge, this is the first report of the urease-producing ability and potential for MICP of P. stutzeri, P. pseudoalcaligenes, S. stutzeri, and B. aryabhattai. KW - Calcium carbonate KW - Microbially induced carbonate precipitation (MICP) KW - Ureolytic bacteria PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-600888 DO - https://doi.org/10.3390/min14040339 VL - 14 IS - 4 SP - 1 EP - 15 PB - MDPI AN - OPUS4-60088 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Stawski, Tomasz A1 - Karafiludis, Stephanos A1 - Pimentel, Carlos A1 - Montes-Hernández, German A1 - Kochovski, Zdravko A1 - Bienert, Ralf A1 - Weimann, Karin A1 - Emmerling, Franziska A1 - Scoppola, Ernesto A1 - Van Driessche, Alexander E.S. T1 - Solution-driven processing of calcium sulfate: The mechanism of the reversible transformation of gypsum to bassanite in brines N2 - Here, we show that calcium sulfate dihydrate (gypsum) can be directly, rapidly and reversibly converted to calcium sulfate hemihydrate (bassanite) in high salinity solutions (brines). The optimum conditions for the efficient production of bassanite in a short time (<5 min) involve the use of brines with c(NaCl) > 4 M and maintaining a temperature, T > 80 °C. When the solution containing bassanite crystals is cooled down to around room temperature, eventually gypsum is formed. When the temperature is raised again to T > 80 °C, bassanite is rapidly re-precipitated. This contrasts with the better-known behaviour of the bassanite phase in low-salt environments. In low-salinity aqueous solutions, bassanite is considered to be metastable with respect to gypsum and anhydrite, and therefore gypsum-to-bassanite conversion does not occur in pure water. Interestingly, the high-salinity transformation of gypsum-to-bassanite has been reported by many authors and used in practice for several decades, although its very occurrence actually contradicts numerical thermodynamic predictions regarding solubility of calcium sulfate phases. By following the evolution of crystalline phases with in situ and time-resolved X-ray diffraction/scattering and Raman spectroscopy, we demonstrated that the phase stability in brines at elevated temperatures was inaccurately represented in the thermodynamic databases. Most notably for c(NaCl) > 4 M, and T > 80 °C gypsum becomes readily more soluble than bassanite, which induces the direct precipitation of the latter from gypsum. The fact that these transformations are controlled by the solution provides extensive opportunities for precise manipulation of crystal formation. Our experiments confirmed that bassanite remained the sole crystalline phase for many hours before reverting into gypsum. This property is extremely advantageous for practical processing and efficient crystal extraction in industrial scenarios. KW - Industrial and Manufacturing Engineering KW - Strategy and Management KW - General Environmental Science KW - Renewable Energy, Sustainability and the Environment KW - Building and Construction KW - Calcium sulfate KW - Gypsum KW - Bassanite KW - Scattering KW - Raman KW - In situ KW - Synchrotron KW - BESSY KW - MySpot PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-594698 UR - https://www.sciencedirect.com/science/article/pii/S0959652624004591#appsec1 DO - https://doi.org/10.1016/j.jclepro.2024.141012 SN - 0959-6526 VL - 440 SP - 1 EP - 12 PB - Elsevier B.V. AN - OPUS4-59469 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -