TY - JOUR A1 - Montag, D. A1 - Adam, Christian T1 - Rechtliche Vorgaben der Klärschlammverordnung und deren Auswirkungen auf die Phosphor-Rückgewinnung JF - Korrespondenz Abwasser, Abfall N2 - Im Abfalltechnik-Ausschuss der Bund/Länder-Arbeitsgemeinschaft Abfall (LAGA) wurde eine Vollzugshilfe zur Klärschlammverordnung erarbeitet, die nach Verabschiedung durch die Umweltministerkonferenz Mitte Mai 2020 als LAGA-Merkblatt M-39 veröffentlicht wurde. Im vorliegenden vierten Arbeitsbericht der DWA-Arbeitsgruppe KEK-1.1 werden verschiedene Aspekte der ab dem Jahr 2029 geltenden Regelungen aufgegriffen und damit einige Punkte des LAGA M-39 hinsichtlich der technischen Auswirkungen für den Kläranlagenbetreiber konkret ausgeführt. KW - Klärschlamm KW - Klärschlammverordnung KW - Phosphor-Rückgewinnung PY - 2022 SN - 1866-0029 VL - 5 IS - 69 SP - 406 EP - 413 PB - Gesellschaft zur Förderung der Abwassertechnik CY - Hennef AN - OPUS4-55009 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Vogel, Christian A1 - Doolette, A. A1 - Huang, J. T1 - Combining diffusive gradients in thin-films (DGT) and 31P NMR spectroscopy to determine phosphorus species in soil JF - Agricultural & Environmental Letters N2 - The diffusive gradients in thin-films (DGT) technique shows in many publications a superior correlation to the amount of plant-available phosphorus (P) in soil. However, this technique cannot give information on the plant-available P species in soil. Therefore, we combined DGT with solution 31P nuclear magnetic resonance (NMR) spectroscopy. This was achieved by using a modified DGT device in which the diffusive layer had a larger pore size, the binding layer incorporated an adsorption material with a higher capacity, and the device had a larger exposure area. The spectroscopic investigation was undertaken after elution of the deployed DGT binding layer in a NaOH solution. Adsorption tests using solutions of known organic P compounds showed that a sufficient amount of these compounds could be adsorbed on the binding layer in order for them to be analyzed by solution 31P NMR spectroscopy. Furthermore, various intermediates of the hydrolysis of trimetaphosphate in soil could be also analyzed over time. KW - Phosphorus KW - Diffusive gradients in thin-films (DGT) KW - Passive sampling KW - fertilizer PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-545759 DO - https://doi.org/10.1002/ael2.20068 VL - 7 IS - 1 SP - e20068 PB - Wiley online library AN - OPUS4-54575 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Raniro, H.R. A1 - Soares, T.de M. A1 - Adam, Christian A1 - Pavinato, P.S. T1 - Waste-derived fertilizers can increase phosphorus uptake by sugarcane and availability in a tropical soil JF - J. Plant Nutr. Soil. Sci. N2 - The use of highly water-soluble phosphorus (P) fertilizers can lead to P fixation in the soil, reducing fertilization efficiency. Waste-derived, low water-solubility sources can potentially increase sugarcane’s P uptake compared to triple superphosphate by reducing adsorption to the soil. Aims:We aimed to test struvite, hazenite, and AshDec® for their agronomic potential as recycled fertilizers for sugarcane production in a typical tropical soil.We hypothesize that these sources can reduce P fixation in the soil, increasing its availability and sugarcane’s absorption. Methods: In a greenhouse pot experiment, two consecutive sugarcane cycles, 90 days each, were conducted in a Ferralsol. The recovered sources struvite, hazenite, AshDec®, and the conventional triple superphosphate were mixed in the soil in three P doses (30, 60, and 90 mg kg–1), aside a control (nil-P). At both harvests, sugarcane number of sprouts, plant height, stem diameter, dry mass yield, shoot phosphorus, and soil P fractionation were investigated. Results: At 90 days, struvite and hazenite performed better for dry mass yield (70.7 and 68.3 g pot–1, respectively) than AshDec® and triple superphosphate (59.8 and 57.4 g pot–1, respectively) and for shoot P, with 98.1, 91.6, 75.6, and 66.3 mg pot–1, respectively. At 180 days, struvite outperformed all treatments for dry mass yield (95.3 g pot–1) and AshDec® (75.5 mg pot–1) for shoot P. Struvite was 38% and hazenite 21% more efficient than triple superphosphate in P uptake, while AshDec® was 6% less efficient. Soil had higher labile P under struvite, hazenite, and AshDec® than triple superphosphate by the end of the first cycle, while only the later increased nonlabile P by the end of the experiment (180 days). Conclusions:Waste-derived P sources were more efficient in supplying P for sugarcane and delivering labile P in 180 days than triple superphosphate. KW - AshDec KW - Hazenite KW - P-efficiency KW - Recycled sources KW - Struvite PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-544216 DO - https://doi.org/10.1002/jpln.202100410 SN - 1436-8730 SP - 1 EP - 12 PB - Wiley-VCH GmbH AN - OPUS4-54421 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sichler, Theresa Constanze A1 - Adam, Christian A1 - Montag, D. A1 - Barjenbruch, M. T1 - Future nutrient recovery from sewage sludge regarding three different scenarios - German case study JF - Journal of Cleaner Production N2 - Agricultural sewage sludge utilization becomes less important in Germany. In 2017, new fertilizer and waste laws caused the agricultural sewage sludge utilization to collapse by more than a quarter. From 2029, German wastewater treatment plants (WWTPs) must recover phosphorus (P) from sewage sludge if it contains more than 2 wt % P. Agricultural utilization will be prohibited for large WWTPs >100,000 population equivalents (pe) from 2029 and >50,000 pe from 2032. In Germany, each federal state must annually report amounts and quality of agriculturally utilized sewage sludge which was 16% of the total disposal in 2019. The reports of 10 states were evaluated for 2016 and 2017 representing approx. 60% of the total agriculturally used sludge volume. In 2016, 60% of the WWTPs’ sludges exceeded the recovery limit of 2 wt % P which is 70% of the amount of sludge and 85% of the phosphorus load. Other nutrients are not affected by the recovery obligation. However, many P recovery processes recover other nutrients, too. Considering three different scenarios for future German sewage sludge disposal shows that 70–77% of the P load in sewage sludge will probably be recovered in the future. At the same time, this applies for about 0–16% nitrogen, 36–52% of calcium, 31–53% of potassium, and 40–52% of magnesium. However, these recovered nutrients loads can substitute only 1% or less of the commercial fertilizer demand except from phosphorus which is up to 43% of the demand. KW - Sewage sludge KW - Phosphorus recovery KW - Wastewater KW - Sewage sludge disposal PY - 2022 DO - https://doi.org/10.1016/j.jclepro.2021.130130 VL - 333 SP - 1 EP - 10 PB - Elsevier Ltd. CY - Amsterdam AN - OPUS4-54186 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Steckenmesser, D. A1 - Vogel, Christian A1 - Herzel, Hannes A1 - Félix, R. A1 - Adam, Christian A1 - Steffens, D. T1 - Thermal treatment of sewage sludge for phosphorus fertilizer production: a model experiment JF - Journal of Plant Nutrition N2 - Phosphorus (P) resource availability and quality is declining and recycling P-fertilizers from waste materials are becoming increasingly important. One important secondary P resource is sewage sludge (SSL) where P is often bound as aluminum phosphate (Al-P), iron phosphate (Fe-P) and polyphosphate (poly-P), respectively. Thermal treatment in different ways is a promising way in P recycling to produce highly plant-available P-fertilizers. To investigate mechanisms behind transformation of hardly available P-species toward plant-available P forms we treated a model SSL containing different kinds of defined P sources by low-temperature conversion (LTC) at 500 °C and subsequent thermochemical treatment of the LTC product with Na additives (TCT) at 950 °C, respectively. Pot experiments with ryegrass were carried out to determine the plant availability of P of the different treatments. The poly-P (here pyrophosphates) based fertilizers had a very high plant availability after both thermal treatments. During LTC treatment the plant availability of the Fe-P and Al-P variants increased because of the Formation of Fe(II) phosphates and/or pyro-/polyphosphates. Especially the formation of Al-polyphosphate shows a high plant availability. The subsequent TCT further increased strongly the plant availability of the Fe-P variants because of the formation of highly plant-available CaNaPO4. Thus, a direct TCT without prior LTC probably also produce CaNaPO4 and is recommended for Fe-P based SSL. However, a molar Ca/P ratio of � 1 in the fertilizer is favorable for CaNaPO4 formation. Thus, the knowledge on the source of primary P in SSL is essential for choosing the accurate thermal treatment method to produce highly plant-available P-fertilizers from SSL. KW - Phosphorus KW - Sewage sludge KW - X-ray diffraction KW - X-ray absorption near-edge structure (XANES) spectroscopy KW - Fertilizer PY - 2021 DO - https://doi.org/10.1080/01904167.2021.1994595 SN - 0190-4167 VL - 45 IS - 8 SP - 1123 EP - 1133 PB - Taylor & Francis Online AN - OPUS4-53755 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Raniro, H.R. A1 - Teles, A.P. A1 - Pavinato, P.S. A1 - Adam, Christian T1 - Phosphorus solubility and dynamics in a tropical soil under sources derived from wastewater and sewage sludge JF - Journal of Environmental Management N2 - Conventional phosphate fertilizers are usually highly water-soluble and rapidly solubilize when moistened by the soil solution. However, if this solubilization is not in alignment with plants demand, P can react with the soil colloidal phase, becoming less available over time. This is more pronounced in acidic, oxidic tropical soils, with high P adsorption capacity, reducing the efficiency of P fertilization. Furthermore, these fertilizers are derived from phosphate rock, a non-renewable resource, generating an environmental impact. To assess these concerns, waste-recycled P sources (struvite, hazenite and AshDec®) were studied for their potential of reducing P Fixation by the soil and improving the agronomic efficiency of the P fertilization. In our work, we compared the solubilization dynamics of struvite, hazenite, AshDec® to triple superphosphate (TSP) in a sandy clay loam Ferralsol, as well as their effect on solution pH and on soil P pools (labile, moderately-labile and non-labile) via an incubation experiment. Leaching columns containing 50 g of soil with surface application of 100 mg per column (mg col􀀀 1) of P from each selected fertilizer and one control (nil-P) were evaluated for 60 days. Daily leachate samples from the column were analyzed for P content and pH. Soil was stratified in the end and submitted to P fractionation. All results were analyzed considering p < 0.05. Our findings showed that TSP and struvite promoted an acid P release reaction (reaching pHs of 4.3 and 5.5 respectively), while AshDec® and hazenite reaction was alkaline (reaching pHs of 8.4 and 8.5 respectively). Furthermore, TSP promoted the highest P release among all sources in 60 days (52.8 mg col􀀀 1) and showed rapid release dynamic in the beginning, while struvite and hazenite showed late release dynamics and lower total leached P (29.7 and 15.5 mg col􀀀 1 P respectively). In contrast, no P-release was detected in the leachate of the AshDec® over the whole trial period. Struvite promoted the highest soil labile P concentration (7938 mg kg􀀀 1), followed by hazenite (5877 mg kg􀀀 1) and AshDec® (4468 mg kg􀀀 1), all higher than TSP (3821 mg kg􀀀 1), while AshDec® showed high moderately-labile P (9214 mg kg􀀀 1), reaffirming its delayed release potential. KW - Phosphate dynamics KW - Struvite KW - Wastewater KW - Sewage sludge ash KW - CaNaPO4 KW - P speciation PY - 2022 DO - https://doi.org/10.1016/j.jenvman.2021.113984 VL - 302 IS - Part A SP - 113984 PB - Elsevier Ltd. AN - OPUS4-53600 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Herzel, Hannes A1 - Aydin, Zeynep A1 - Adam, Christian T1 - Crystalline phase analysis and phosphorus availability after thermochemical treatment of sewage sludge ash with sodium and potassium sulfates for fertilizer production JF - Journal of Material Cycles and Waste Management N2 - Phosphorus rich sewage sludge ash is a promising source to produce phosphorus recycling fertilizer. However, the low plant availability of phosphorus in these ashes makes a treatment necessary. A thermochemical treatment (800–1000 °C) with alkali additives transforms poorly plant available phosphorus phases to highly plant available calcium alkali Phosphates (Ca,Mg)(Na,K)PO4. In this study, we investigate the use of K2SO4 as additive to produce a phosphorus potassium fertilizer in laboratory-scale experiments (crucible). Pure K2SO4 is not suitable as high reaction temperatures are required due to the high melting point of K2SO4. To overcome this barrier, we carried out series of experiments with mixtures of K2SO4 and Na2SO4 resulting in a lower economically feasible reaction temperature (900–1000 °C). In this way, the produced phosphorus potassium fertilizers (8.4 wt.% K, 7.6 wt.% P) was highly plant available for phosphorus indicated by complete extractable phosphorus in neutral ammonium citrate solution. The added potassium is, in contrast to sodium, preferably incorporated into silicates instead of phosphorus phases. Thus, the highly extractable phase (Ca,Mg)(Na,K)PO4 in the thermochemical products contain less potassium than expected. This preferred incorporation is confirmed by a pilot-scale trial (rotary kiln) and thermodynamic calculation. KW - Phosphorus recovery KW - Recycling fertilizer KW - Calcium alkali phosphate KW - Silicate PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-536276 DO - https://doi.org/10.1007/s10163-021-01288-3 SN - 1611-8227 IS - 23 SP - 2242 EP - 2254 PB - Springer AN - OPUS4-53627 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rieger, J. A1 - Colla, V. A1 - Matino, I. A1 - Branca, T. A. A1 - Stubbe, G. A1 - Panizza, A. A1 - Brondi, C. A1 - Falsafi, M. A1 - Hage, J. A1 - Wang, X. A1 - Voraberger, B. A1 - Fenzl, T. A1 - Masaguer, V. A1 - Faraci, E. L. A1 - di Sante, L. A1 - Cirilli, F. A1 - Loose, Florian A1 - Thaler, C. A1 - Soto, A. A1 - Frittella, P. A1 - Foglio, G. A1 - di Cecca, C. A1 - Tellaroli, M. A1 - Corbella, M. A1 - Guzzon, M. A1 - Malfa, E. A1 - Morillon, A. A1 - Algermissen, D. A1 - Peters, K. A1 - Snaet, D. T1 - Residue Valorization in the Iron and Steel Industries: Sustainable Solutions for a Cleaner and More Competitive Future Europe JF - Metals N2 - The steel industry is an important engine for sustainable growth, added value, and high-quality employment within the European Union. It is committed to reducing its CO2 emissions due to production by up to 50% by 2030 compared to 1990′s level by developing and upscaling the technologies required to contribute to European initiatives, such as the Circular Economy Action Plan (CEAP) and the European Green Deal (EGD). The Clean Steel Partnership (CSP, a public–private partnership), which is led by the European Steel Association (EUROFER) and the European Steel Technology Platform (ESTEP), defined technological CO2 mitigation pathways comprising carbon direct avoidance (CDA), smart carbon usage SCU), and a circular economy (CE). CE ap-proaches ensure competitiveness through increased resource efficiency and sustainability and consist of different issues, such as the valorization of steelmaking residues (dusts, slags, sludge) for internal recycling in the steelmaking process, enhanced steel recycling (scrap use), the use of secondary carbon carriers from non-steel sectors as a reducing agent and energy source in the steelmaking process chain, and CE business models (supply chain analyses). The current paper gives an overview of different technological CE approaches as obtained in a dedicated workshop called “Resi4Future—Residue valorization in iron and steel industry: sustainable solutions for a cleaner and more competitive future Europe” that was organized by ESTEP to focus on future challenges toward the final goal of industrial deployment. KW - Circular economy KW - Steelmaking residues KW - Clean steel PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-530350 DO - https://doi.org/10.3390/met11081202 VL - 11 IS - 8 SP - 1202 PB - MDPI AN - OPUS4-53035 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Weimann, Karin A1 - Adam, Christian A1 - Buchert, M. A1 - Sutter, J. T1 - Environmental Evaluation of Gypsum Plasterboard Recycling JF - Minerals N2 - Gypsum is widely used in the construction sector and its worldwide consumption has been increasing for several decades. Depending on the life-time of the used gypsum products, an increase of gypsum in construction and demolition waste follows. Especially against the background of a circular economy, the recycling of waste gypsum is of growing importance. However, the use of recycled gypsum makes only sense if it is environmentally friendly. Therefore, an evaluation of the environmental impacts of an industrial-scale processing for the recycling of post-consumer gypsum waste was conducted. The evaluation was performed with an established life cycle assessment software. Original data provided by industry and complementary data from a database for life cycle assessments were used for the calculations. Two scenarios for recycled gypsum with different transportation distances were calculated. These results are compared with results of the environmental evaluation of gypsum derived from coal-fired power plants (FGD gypsum) and natural gypsum. The results show that utilization of recycled gypsum can be environmentally advantageous compared to the use of natural gypsum or FGD gypsum, especially in the impact categories land transformation and resource consumption (abiotic depletion potential). For most environmental impact categories the specific transportation distances have a strong influence. KW - Gypsum plasterboards KW - Gypsum waste KW - Recycled gypsum KW - Environmental evaluation PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-522321 DO - https://doi.org/10.3390/min11020101 SN - 2075-163X VL - 11 IS - 2 SP - 101 PB - MDPI CY - Basel, Schweiz AN - OPUS4-52232 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schraut, Katharina A1 - Adamczyk, Burkart A1 - Adam, Christian A1 - Stephan, D. A1 - Meng, Birgit A1 - Simon, Sebastian A1 - von Werder, Julia T1 - Synthesis and characterisation of alites from reduced basic oxygen furnace slags JF - Cement and Concrete Research N2 - Basic oxygen furnace slags (BOFS) are by-products of the steelmaking process. Several researchers have studied the production of Portland cement clinker and metallic iron from BOFS via a reductive treatment. In this study, we applied a carbothermal reduction of BOFS in a technical-scale electric arc furnace and characterised the clinker-like products. Those clinker-like non-metallic products (NMPs) had a chemical and mineralogical composition comparable to clinker for ordinary Portland cement (OPC) and contained large elongated alite crystals as major component. The pure NMPs reacted more slowly and achieved a lower degree of hydration compared with commercial OPC. If the reactivity of the products can be further increased by employing specific adaptations, it can be used as a full clinker substitute for OPC. Nevertheless, it is also an option to use the material without further modifications as a cement component or concrete addition, which contributes to the strength development in both cases. KW - BOFS KW - Hydration products KW - Thermal analysis KW - X-ray diffraction PY - 2021 DO - https://doi.org/10.1016/j.cemconres.2021.106518 SN - 0008-8846 VL - 147 SP - 6518 PB - Elsevier Ltd. AN - OPUS4-52939 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schraut, Katharina A1 - Kargl, F. A1 - Adam, Christian A1 - Ivashko, O. T1 - In situ synchrotron XRD measurements during solidification of a melt in the CaO–SiO2 system using an aerodynamic levitation system JF - Journal of Physics: Condensed Matter N2 - Phase formation and evolution was investigated in the CaO–SiO2 system in the range of 70–80 mol% CaO. The samples were container-less processed in an aerodynamic levitation system and crystallization was followed in situ by synchrotron x-ray diffraction at the beamline P21.1 at the German electron synchrotron (DESY). Modification changes of di- and tricalcium silicate were observed and occurred at lower temperatures than under equilibrium conditions. Despite deep sample undercooling, no metastable phase formation was observed within the measurement timescale of 1 s. For the given cooling rates ranging from 300 K s−1 to about 1 K s−1, no decomposition of tricalcium silicate was observed. No differences in phase evolution were observed between reducing and oxidizing conditions imposed by the levitation gas (Ar and Ar + O2). We demonstrate that this setup has great potential to follow crystallization in refractory oxide liquids in situ. For sub-second primary phase formation faster detection and for polymorph detection adjustments in resolution have to be implemented. KW - Aerodynamic levitation KW - Calcium silicate KW - Phase formation KW - Oxide melts KW - In situ synchrotron x-ray diffraction PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-526952 DO - https://doi.org/10.1088/1361-648X/abf7e1 VL - 33 IS - 26 SP - 264003 (12pp) PB - IOP Publishing AN - OPUS4-52695 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gentzmann, Marie A1 - Paul, Andrea A1 - Serrano, Juan A1 - Adam, Christian T1 - Understanding scandium leaching from bauxite residues of different geological backgrounds using statistical design of experiments JF - Journal of Geochemical Exploration N2 - The leaching behavior of scandium (Sc) from bauxite residues can differ significantly when residues of different geological backgrounds are compared. The mineralogy of the source rock and the physicochemical environment during bauxitization affect the association of Sc in the bauxite i.e., how Sc is distributed amongst different mineral phases and whether it is incorporated in and/or adsorbed onto those phases. The Sc association in the bauxite is in turn crucial for the resulting Sc association in the bauxite residue. In this study systematic leaching experiments were performed on three different bauxite residues using a statistical design of experiments approach. The three bauxite residues compared originated from processing of lateritic and karstic bauxites from Germany, Hungary, and Russia. The recovery of Sc and Fe was determined by ICP-OES measurements. Mineralogical changes were analyzed by X-ray-diffraction and subsequent Rietveld refinement. The effects of various parameters including temperature, acid type, acid concentration, liquid-to-solid ratio and residence time were studied. A response surface model was calculated for the selected case of citric acid leaching of Hungarian bauxite residue. The investigations showed that the type of bauxite residue has a strong influence. The easily leachable fraction of Sc can vary considerably between the types, reaching ~20–25% in German Bauxite residue and ~50% in Russian bauxite residue. Mineralogical investigations revealed that a major part of this fraction was released from secondary phases such as cancrinite and katoite formed during Bayer processing of the bauxite. The effect of temperature on Sc and Fe recovery is strong especially when citric acid is used. Based on the exponential relationship between temperature and Fe-recovery it was found to be particularly important for the selectivity of Sc over Fe. Optimization of the model for a maximum Sc recovery combined with a minimum Fe recovery yielded results of ~28% Sc recovery at <2% Fe recovery at a temperature of 60 ◦C, a citric acid normality of 1.8, and a liquid-to-solid ratio of 16 ml/g. Our study has shown that detailed knowledge about the Sc association and distribution in bauxite and bauxite residue is key to an efficient and selective leaching of Sc from bauxite residues. KW - Bauxite residue KW - Scandium KW - Leaching KW - Design of experiments KW - Red mud PY - 2022 DO - https://doi.org/10.1016/j.gexplo.2022.107041 SN - 0375-6742 VL - 2022 IS - 240 SP - 1 EP - 13 PB - Elsevier Science CY - Amsterdam AN - OPUS4-55531 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Sichler, Theresa Constanze A1 - Adam, Christian A1 - Barjenbruch, M. A1 - Montag, D. A1 - Mauch, Tatjana A1 - Sommerfeld, Thomas A1 - Ehm, J.H. T1 - Variation of the element composition of municipal sewage sludges in the context of new regulations on phosphorus recovery in Germany JF - Environmental Sciences Europe N2 - Phosphorus (P) recovery is obligatory for all sewage sludges with more than 20 g P/kg dry matter (DM) from 2029 in Germany. Nine wastewater treatment plants (WWTPs) were chosen to investigate variations of phosphorus contents and other parameters in sewage sludge over the year. Monthly sewage sludge samples from each WWTP were analyzed for phosphorus and other matrix elements (C, N, H, Ca, Fe, Al, etc.), for several trace elements (As, Cr, Mo, Ni, Pb, Sn) and loss of ignition. Among the nine WWTPs, there are four which have phosphorus contents both above and below the recovery limit of 20 g/kg DM along the year. Considering the average phosphorus content over the year, only one of them is below the limit. Compared to other matrix elements and parameters, phosphorus fuctuations are low with an average of 7% over all nine WWTPs. In total, only hydrogen and carbon are more constant in the sludge. In several WWTPs with chemical phosphorus elimination, phosphorus fuctuations showed similar courses like iron and/or aluminum. WWTPs with chamber flter presses rather showed dilution efects of calcium dosage. As result of this study, monthly phosphorus measurement is highly recommended to determine whether a WWTP is below the 20 g/kg DM limit. KW - Sewage sludge KW - Phosphorus recovery KW - Wastewater KW - Phosphorus elimination PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-557499 DO - https://doi.org/10.1186/s12302-022-00658-4 SN - 2190-4707 VL - 34 IS - 1 SP - 1 EP - 12 PB - Springer Nature CY - Berlin AN - OPUS4-55749 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Neuhold, S. A1 - Algermissen, D. A1 - Drissen, P. A1 - Adamczyk, Burkart 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 JF - Applied Science 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 (EAF) slags KW - FactSageTM calculations KW - Leaching control mechanisms KW - Melting experiments PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-571517 DO - https://doi.org/10.3390/app10072549 VL - 10 IS - 7 SP - 1 EP - 18 PB - MDPI AN - OPUS4-57151 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Machado Ferreira de Araujo, F. A1 - Duarte-Ruiz, D. A1 - Saßnick, H.-D. A1 - Gentzmann, Marie C. A1 - Huthwelker, T. A1 - Cocchi, C. T1 - Electronic Structure and Core Spectroscopy of Scandium Fluoride Polymorphs JF - Inorganic Chemistry N2 - Microscopic knowledge of the structural, energetic, and electronic properties of scandium fluoride is still incomplete despite the relevance of this material as an intermediate for the manufacturing of Al−Sc alloys. In a work based on first-principles calculations and X-ray spectroscopy, we assess the stability and electronic structure of six computationally predicted ScF3 polymorphs, two of which correspond to experimentally resolved single-crystal phases. In the theoretical analysis based on density functional theory (DFT), we identify similarities among the polymorphs based on their formation energies, chargedensity distribution, and electronic properties (band gaps and density of states). We find striking analogies between the results obtained for the ow- and high-temperature phases of the material, indirectly confirming that the transition occurring between them mainly consists of a rigid rotation of the lattice. With this knowledge, we examine the X-ray absorption spectra from the Sc and F K-edge contrasting firstprinciples results obtained from the solution of the Bethe−Salpeter equation on top of all-electron DFT with high-energy-resolution fluorescence detection measurements. Analysis of the computational results sheds light on the electronic origin of the absorption maxima and provides information on the prominent excitonic effects that characterize all spectra. A comparison with measurements confirms that the sample is mainly composed of the high- and low-temperature polymorphs of ScF3. However, some fine details in the experimental results suggest that the probed powder sample may contain defects and/or residual traces of metastable polymorphs. KW - Scandium KW - X-ray spectroscopy PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-570727 DO - https://doi.org/10.1021/acs.inorgchem.2c04357 SN - 0020-1669 VL - 62 IS - 10 SP - 4238 EP - 4247 PB - ACS Publications CY - Washington DC AN - OPUS4-57072 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Steckenmesser, D. A1 - Vogel, Christian A1 - Böhm, L. A1 - Heyde, B. A1 - Adam, Christian T1 - Fate of heavy metals and polycyclic aromatic hydrocarbons (PAH) in sewage sludge carbonisates and ashes – A risk assessment to a thermochemical phosphorus-recycling process JF - Waste Management N2 - In the near future, phosphorus (P) recycling will gain importance in terms of decreasing primary resources. Sewage sludge (SSL) is an adequate secondary P-resource for P-fertilizer production but it is also a sink for heavy metals and organic pollutants. The present study is an investigation on thermochemical P-recycling of SSL. Various temperatures and amendments were tested regarding their performance to remove heavy metals and polycyclic aromatic hydrocarbons (PAH) and simultaneous increase of the plant-availability of P. The investigations were carried out on two types of SSL originating from wastewater treatment plants with chemical P-precipitation and enhanced biological P-removal, respectively. The results show that thermochemical treatment with chlorine donors is suitable to remove the majority of heavy metals and that a combination of a gaseous chlorine donor (HCl) and sodium additives leads to both high heavy metal removal and high plant availability of P. Furthermore, plant experiments Show that almost all investigated thermochemical treatments can significantly reduce the bioavailability and plant uptake of heavy metals. Furthermore, PAHs are secondarily formed during low-temperature treatments (400–500 ° ), but can be significantly reduced by using sodium carbonate as an additive. KW - Fertilzer KW - Pollutant KW - Phosphorus PY - 2018 DO - https://doi.org/10.1016/j.wasman.2018.06.027 SN - 0956-053X VL - 78 SP - 576 EP - 587 PB - Elsevier Ltd. CY - Amsterdam AN - OPUS4-45341 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Huber, F. A1 - Herzel, Hannes A1 - Adam, Christian A1 - Mallow, O. A1 - Blasenbauer, D. A1 - Fellner, J. T1 - Combined disc pelletisation and thermal treatment of MSWI fly ash JF - Waste Management N2 - An environmentally friendly and cost efficient way for the management of municipal solid waste incineration (MSWI) fly ash represents its thermal co-treatment together with combustible waste. However, the safe introduction and storage of MSWI fly ash in the waste bunker is challenging and associated with severe problems (e.g. dust emissions, generation of undefined lumps and heat in case of moistened MSWI fly ash). Therefore, the aim of this study is to investigate the suitability of pelletisation as a pretreatment of MSWI fly ash. In particular, MSWI fly ash was characterised after sampling, pelletisation and thermal treatment and the transfer of constituents to secondary fly ash and flue gas was investigated. For this purpose, MSWI fly ash pellets with a water content of about 0.15 kg/kg and a diameter of about 8 mm have been produced by disc pelletiser and treated in an electrically heated pilot-scale rotary kiln at different temperatures, ranging from 450°C to 1050°C. The total contents of selected elements in the MSWI fly ash before and after thermal treatment and in the generated secondary fly ash have been analysed in order to understand the fate of each element. Furthermore, leachable contents of selected elements and total content of persistent organic pollutants of the thermally treated MSWI fly ash were determined. Due to the low total content of Hg (0.7 mg/kg) and the low leachate content of Pb (<0.36 mg/kg), even at the lowest treatment temperature of 450°C, thermally treated MSWI fly ash pellets can be classified as nonhazardous waste. However, temperatures of at least 650°C are necessary to decrease the toxic equivalency of PCDD/F and DL-PCB. The removal of toxic heavy metals like Cd and Pb is significantly improved at temperatures of 850°C, 950°C or even 1050°C. The observed metal removal led to relatively high contents of e.g. Cu (up to 11,000 mg/kg), Pb (up to 91,000 mg/kg) and Zn (up to 21,000 mg/kg) in the secondary fly ash. This metal enriched secondary fly ash might represent a potential raw material for metal recovery (e.g. via acidic leaching). Due to the high content of total dissolved solids observed in the leachate of thermally treated MSWI fly ash pellets, a wet extraction procedure is suggested to enable its safe disposal at non-hazardous waste landfills. KW - MSWI fly ash KW - Thermal treatment PY - 2018 DO - https://doi.org/10.1016/j.wasman.2017.12.020 SN - 0956-053X VL - 73 SP - 381 EP - 391 PB - Elsevier Ltd. CY - Rotterdam AN - OPUS4-44481 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Smol, M. A1 - Adam, Christian A1 - Kugler, Stefan T1 - Analiza możliwości wykorzystania w Polsce popiołów ze spalania komunalnych osadów ściekowych na cele nawozowe T1 - Use of municipal sewage sludge ash for fertilizing purposes. An analysis of possibilities in Poland JF - Przemysł Chemiczny N2 - Popioły pochodzące z instalacji do spalania komunalnych osadów ściekowych, znajdującej się na terytorium Polski, poddano procesom termochemicznego przekształcania, dzięki czemu otrzymano produkty nawozowe spełniające kryteria dopuszczające je do obrotu jako nawozy mineralne. Ponadto dokonano analizy możliwości wykorzystania popiołów na cele nawozowe zgodnie z obecnie przyjętymi dokumentami strategicznymi i planistycznymi dotyczącymi gospodarki odpadami na poziomie krajowym i europejskim. N2 - Ashes from thermal transformation of municipal sewage sludge were thermochem. modified at 1000°C in the presence of NaHCO3 and sewage sludge to obtain CaNaPO4 and reduce the content of heavy metals in the produced fertilizer. Its bioavailability was more than 99% higher than that of raw ashes (50%). The nutrient content was 13.56 % Ca, 6.33% P, 4.36% K and 5.0% Fe. The content of heavy metals in fertilizer products met the std. requirements and was exceeded only in the case of Pb (278.3 mg/kg d.m.). KW - Ashes KW - Waste KW - Phosphorus KW - Recovery KW - Fertilizer PY - 2020 DO - https://doi.org/10.15199/62.2020.8.14 VL - 99 IS - 8 SP - 1186 EP - 1191 AN - OPUS4-51267 LA - pol AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kaufmann, Felix E.D. A1 - Hoffmann, Marie C. A1 - Bachmann, Kai A1 - Veksler, Ilya V. A1 - Trumbull, Robert B. A1 - Hecht, Lutz T1 - Variations in composition, texture, and platinum group element mineralization in the lower group and middle group chromitites of the Northwestern Bushveld Complex, South Africa JF - Economic Geology N2 - Small-scale variations in mineral chemistry, textures, and platinum group element (PGE) mineralization were investigated in the Lower and Middle Group chromitite layers LG6, LG6a, MG1, MG2, and MG2 II from vertical drill core profiles at the Thaba mine in the northwestern limb of the Bushveld Complex. We present detailed geochemical profiles of chromite composition and chromite crystal size distribution curves to shed light on the processes of chromite accumulation and textural modification as well as mineralization. Multiple samples within each layer were assayed for PGE concentrations, and the respective platinum group mineral association was determined by mineral liberation analysis (MLA). There is strong evidence for postcumulus changes in the chromitites. The crystal size distribution curves suggest that the primary chromite texture was coarsened by a combination of adcumulus growth and textural equilibration, while compaction of the crystal mush played only a minor role. Mineral compositions were also modified by postcumulus processes, but because of the very high modal amount of chromite and its local preservation in orthopyroxene oikocrysts, that phase retained much primary information. Vertical variations of chromite composition within chromitite layers and from one layer to another do not support the idea of chromite accumulation from crystal-rich slurries or crystal settling from a large magma chamber. Instead, we favor a successive buildup of chromitite layers by repeated injections of relatively thin layers of chromite-saturated magmas, with in situ crystallization occurring at the crystal mush-magma interface. The adcumulus growth of chromite grains to form massive chromitite required addition of Cr to the layers, which we attribute to downward percolation from the overlying magma. The PGE concentrations are elevated in all chromitite layers compared to adjacent silicate rocks and show a systematic increase upward from LG6 (avg 807 ppb Ir + Ru + Rh + Pt + Pd + Au) to MG2 II (avg 2,062 ppb). There are also significant internal variations in all layers, with enrichments at hanging and/or footwalls. The enriched nature of chromitites in PGEs compared to host pyroxenites is a General feature, independent of the layer thickness. The MLA results distinguish two principal groups of PGE mineral associations: the LG6, LG6, and MG1 are dominated by the malanite series, laurite, and PGE sulfarsenides, while the MG2 and MG2 II layers are characterized by laurite and PGE sulfides as well as Pt-Fe-Sn and PGE-Sb-Bi-Pb alloys. Differences in the PGE associations are attributed to postcumulus alteration of the MG2 and MG2 II layer, while the chromitites below, particularly LG6 and LG6a, contain a more pristine association. KW - Bushveld Complex KW - Chromitites KW - Platinum PY - 2019 DO - https://doi.org/10.5382/econgeo.4641 SN - 0361-0128 VL - 114 IS - 3 SP - 569 EP - 590 PB - Society of Economic Geologists AN - OPUS4-48145 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Taube, Mareike Carolin A1 - Adamczyk, Burkart A1 - Adam, Christian A1 - Feldmann, Ines A1 - Ostermann, Markus A1 - Reuter, M. A1 - Stelter, M. T1 - Tantalrecycling aus pyrometallurgischen Rückständen JF - World of Metallurgy – ERZMETALL N2 - Gegenstand dieser Arbeit ist die Untersuchung eines bestehenden pyrometallurgischen Prozesses zur Rückgewinnung von Tantal und Niob aus metallurgischen Reststoffen mit vorwiegend niedriger Wertstoffkonzentration. Zur näheren Erforschung der im vorliegenden Stoffsystem ablaufenden Reduktionsprozesse wurden in einem Elektrolichtbogenofen Schmelzversuche im Pilotmaßstab durchgeführt. Als Reduktionsmittel diente Koks, welcher mithilfe einer Argon-gespülten Eisenlanze in die flüssige mineralische Schmelze eingebracht wurde. Während der Reduktionsbehandlung werden Refraktärmetalle wie Tantal und Niob in ihre Carbide überführt und anschließend in der erschmolzenen eisenbasierten Metallphase am Boden des Reaktors angereichert. Neben Tantal und Niob gelangt auch ein Teil des im Einsatzmaterial enthaltenen Titans als unerwünschtes Begleitelement in die Metallphase. Sein Großteil verbleibt jedoch als Oxid in der Schlacke und wird dort hauptsächlich im Mineral Perowskit (CaTiO3) gebunden. Die erstarrten Schlackeproben wurden mit verschiedenen Methoden wie Röntgenfluoreszensanalyse, Röntgenbeugung und Rasterelektronenmikroskopie mit gekoppelter energiedispersiver Röntgenanalyse untersucht, um die Bildung tantalhaltiger Mineralphasen zu verschiedenen Stadien des Reduktionsprozesses zu verfolgen. Die hier gewonnenen Erkenntnisse zeigen, dass weniger die durch das Einblasen von Koks verursachte Reduktionsreaktion, sondern das Absinken der tantalreichen Eisentröpfchen in der flüssigen mineralischen Schmelze, gefolgt von ihrer Anreicherung in die Metallphase, für die Kinetik ausschlaggebend ist. N2 - An existing pyrometallurgical process for tantalum and niobium recovery, mainly from low grade pyrometallurgical residues, was investigated. Melting experiments were carried out in a pilot-scale electric arc furnace to study the material system during the reduction process caused by blowing coke into the liquid mineral melt. During the pyrometallurgical treatment refractory metals such as tantalum and niobium are converted into their carbides and enriched in the molten iron-based metal phase. Titanium is also enriched in the metal phase as an unwanted accompanying element, but most of it remains in oxidic form in the slag and is mainly bound in the mineral perovskite. Cooled down slag samples were analysed using XRF, XRD, SEM and EDX to investigate the formation of mineral phases rich in tantalum during various stages of the reduction process. The results show that the settling of the tantalum-rich iron droplets in the molten slag into the metal phase May play a greater role for the kinetics than the actual reduction reaction caused by blowing in coke. KW - Tantal KW - Recycling KW - Reduktionsprozess KW - Perowskit KW - Elektrolichtbogenofen PY - 2020 SN - 1613-2394 VL - 73 IS - 4 SP - 196 EP - 205 PB - GDMB Verlag GmbH CY - Clausthal-Zellerfeld AN - OPUS4-51064 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -