TY - CONF A1 - Sichler, Theresa A1 - Adam, Christian A1 - Montag, D. A1 - Ehm, J.H. T1 - Schwankungen der P-Gehalte in Klärschlämmen im Kontext der Klärschlammverordnung T2 - KlärschlammTage Tagungsband N2 - Ab 2029 gilt für alle Kläranlagen in Deutschland eine Pflicht zur Rückgewinnung von Phosphor (P) aus Klärschlamm. Ausgenommen sind nur Anlagen mit Schlämmen mit weniger als 20 g P/kg bezogen auf die Trockenmasse (TM). Für eine Überprüfung der Phosphorschwankungen im Klärschlamm wurden neun verschiedene Kläranlagen ausgewählt mit Phosphorgehalten nahe der "Rückgewinnungsgrenze" von 20 g/kg TM. Der entwässerte Klärschlamm dieser Anlagen wurde monatlich beprobt und auf seinen Phosphorgehalt geprüft. Die Phosphorschwankungen betrugen je nach Anlage zwischen 4 % und 13 % (relative Standardabweichung), im Mittel rund 7 %. T2 - KlärschlammTage CY - Online Meeting DA - 09.06.2021 KW - Phosphor KW - Klärschlamm KW - Phosphorrückgewinnung KW - Abwasserbehandlung KW - Klärschlammverordnung PY - 2021 SP - 102 EP - 108 PB - Deutsche Vereinigung für Wasserwirtschaft, Abwasser und Abfall e. V. (DWA) CY - Hennef AN - OPUS4-52839 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Sichler, Theresa T1 - Schwankungen der P-Gehalte in Klärschlämmen im Kontext der Klärschlammverordnung N2 - Es wurden die Schwankungen der Phosphorgehalte in kommunalem Klärschlamm vorgestellt. Dazu wurden von 9 Kläranlagen monatlich Klärschlammproben genommen und auf P untersucht. T2 - KlärschlammTage CY - Online Meeting DA - 09.06.2021 KW - Phosphor KW - Klärschlamm KW - Phosphorrückgewinnung KW - Abwasserbehandlung KW - Klärschlammverordnung PY - 2021 AN - OPUS4-52840 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Piehl, Patrick A1 - Weingart, E. A1 - Adam, Christian T1 - Recovery of zinc from steel mill dusts in the rotary kiln by joint treatment with chloride-containing residues N2 - During iron and steel production, several by-products such as slags, dusts and sludges are generated in addition to pig iron and steel as primary products. While established recycling routes exist for slags, there are still considerable recycling problems for other residual materials, especially for filter dusts and sludges containing zinc and lead from waste gas purification. However, the high heavy metal contents make landfilling these dusts and sludges cost-intensive and ecologically problematic. In addition, the relatively high zinc and iron loads represent a valuable material potential, which can make reprocessing of the material with recovery of the zinc and iron loads as secondary raw materials ecologically as well as economically attractive. Against this background, a process is being developed in a cooperative project between Ferro Duo GmbH and the Federal Institute for Materials Research and Testing (BAM), in which the heavy metals (zinc, lead, cadmium, etc.) contained in the filter dusts and sludges are selectively converted into chlorides in a thermochemical process after the addition of a chlorine donor and evaporated at temperatures between 650 and 1100 °C. This process can be used to recover zinc and iron as secondary raw materials. Experiments to date in a batch reactor show that >99% of the zinc and lead can be removed from the treated material. However, a continuous process is necessary for an economical process, which is why this process is transferred to a rotary kiln and relevant process parameters are identified and optimized. The results of these investigations will be presented here. T2 - European Congress and Exhibition on Advanced Materials and Processes 2021 CY - Online meeting DA - 13.09.2021 KW - Elektroofenstaub KW - Gichtgasschlamm KW - Recycling KW - Ressourcenrückgewinnung KW - Zink PY - 2021 AN - OPUS4-53290 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hamann, Christopher A1 - Spanka, M. A1 - Stolle, Dirk A1 - Auer, G. A1 - Weingart, Eric A1 - Al-Sabbagh, Dominik A1 - Ostermann, Markus A1 - Adam, Christian T1 - Recycling of blast-furnace sludge by thermochemical treatment with spent iron(II) chloride solution from steel pickling JF - Journal of hazardous materials N2 - One of the typical wastes produced in blast-furnace (BF) ironmaking is BF sludge, which mostly consists of carbon and iron oxides, but also contains toxic trace metals such as Zn, Pb, Cd, As, and Hg that render the material hazardous. Due to the lack of an established recycling process, BF sludges are landfilled, which is ecologically questionable and costly. Here, we investigate selective removal of Zn, Pb, and Cd from BF sludge by chlorination–evaporation reactions using thermodynamic modelling and laboratory-scale experiments. Specifically, BF sludge was thermochemically treated at 650–1000 °C with a spent iron(II) chloride solution from steel pickling and the effects of process temperature and retention time on removal of Zn, Pb, and Cd were investigated. Zinc and Pb were quantitatively removed from BF sludge thermochemically treated at 900–1000 °C, whereas Fe and C as well as other major elements were mostly retained. The Zn, Pb, and Cd contents in the thermochemically treated BF sludge could be lowered from ∼56 g/kg, ∼4 g/kg, and ∼0.02 g/kg to ≤0.7 g/kg, ≤0.02 g/kg, and ≤0.008 g/kg, respectively, thus rendering the processed mineral residue a non-hazardous raw material that may be re-utilized in the blast furnace or on the sinter band. KW - Blast-furnace sludge KW - Selective chlorination KW - Zinc chloride PY - 2021 DO - https://doi.org/https://doi.org/10.1016/j.jhazmat.2020.123511 SN - 0304-3894 VL - 402 IS - 123511 SP - 1 EP - 12 PB - Elsevier CY - Amsterdam AN - OPUS4-51141 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Vogel, Christian A1 - Helfenstein, J. A1 - Massey, M. A1 - Sekine, R. A1 - Kretzschmar, R. A1 - Beiping, L. A1 - Peter, T. A1 - Chadwick, O. A1 - Tamburini, F. A1 - Rivard, C. A1 - Herzel, Hannes A1 - Adam, Christian A1 - Pradas del Real, A. A1 - Castillo-Michel, H. A1 - Zuin, L. A1 - Wang, D. A1 - Félix, R. A1 - Lassalle-Kaiser, B. A1 - Frossard, E. T1 - Microspectroscopy reveals dust-derived apatite grains in acidic, highly-weathered Hawaiian soils JF - Geoderma N2 - Dust deposition is an important source of phosphorus (P) to many ecosystems. However, there is little evidence of dust-derived P-containing minerals in soils. Here we studied P forms along a well-described climatic Gradient on Hawaii, which is also a dust deposition gradient. Soil mineralogy and soil P forms from six sites along the climatic gradient were analyzed with bulk (X-ray diffraction and P K-edge X-ray absorption near edge structure) and microscale (X-ray fluorescence, P K-edge X-ray absorption near edge structure, and Raman) analysis methods. In the wettest soils, apatite grains ranging from 5 to 30 μm in size were co-located at the micro-scale with quartz, a known continental dust indicator suggesting recent atmospheric deposition. In addition to co-location with quartz, further evidence of dust-derived P included backward trajectory modeling indicating that dust particles could be brought to Hawaii from the major global dust-loading areas in central Asia and northern Africa. Although it is not certain whether the individual observed apatite grains were derived from long-distance transport of dust, or from local dust sources such as volcanic ash or windblown fertilizer, these observations offer direct evidence that P-containing minerals have reached surface layers of highly-weathered grassland soils through atmospheric deposition. KW - Phosphorus KW - soil KW - microspectroscopy KW - Raman spectroscopy KW - XANES spectroscopy KW - x-ray diffraction PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-511522 DO - https://doi.org/10.1016/j.geoderma.2020.114681 SN - 0166-0918 SN - 1872-6259 VL - 381 SP - 114681-1 EP - 114681-11 PB - Elsevier CY - Amsterdam AN - OPUS4-51152 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gentzmann, Marie A1 - Schraut, Katharina A1 - Vogel, Christian A1 - Gäbler, H.-E. A1 - Huthwelker, T. A1 - Adam, Christian T1 - Investigation of scandium in bauxite residues of different origin JF - Applied Geochemistry N2 - This paper focuses on the scandium speciation in bauxite residues of different origin. Insights into mineralchemical similarities and differences of these materials will be presented and links to their natural geological background discussed. The presented research should provide fundamental knowledge for the future development of efficient and viable technologies for Sc-recovery from bauxite residues derived from different bauxites and accumulating at different localities. In total, five bauxite residues were investigated which originated from Greece, Germany, Hungary and Russia (North Ural & North Timan) using a combination of different analytical tools. Those included: laser ablation inductively coupled plasma mass spectrometry, X-ray absorption near Edge structure (XANES) spectroscopy, μ-Raman spectroscopy as well as scanning electron microscopy and electron microprobe analyses. X-ray fluorescence and inductively coupled plasma mass spectrometry were used to determine the overall chemical composition. The investigated samples were found to exhibit a relatively homogenous distribution of Sc between the larger mineral particles and the fine-grained matrix except for Al-phases like diaspore, boehmite and gibbsite. These phases were found to be particularly low in Sc. The only sample where Sc mass fractions in Al-phases exceeded 50 mg/kg was the Russian sample from North Ural. Fe-phases such as goethite, hematite and chamosite (for Russian samples) were more enriched in Sc than the Al-phases. In fact, in Greek samples goethite showed a higher capacity to incorporate or adsorb Sc than hematite. Accessory minerals like zircon, rutile/anatase and ilmenite were found to incorporate higher mass fractions of Sc (>150 mg/kg), however, those minerals are only present in small amounts and do not represent major host phases for Sc. In Russian samples from North Ural an additional Ca–Mg rich phase was found to contain significant mass fractions of Sc (>500 mg/kg). μ-XANES spectroscopy was able to show that Sc in bauxite residue occurs adsorbed onto mineral surfaces as well as incorporated into the crystal lattice of certain Fe-phases. According to our observations the bauxite type, i.e. karstic or lateritic, the atmospheric conditions during bauxitization, i.e. oxidizing or reducing, and consequently the dominant Sc-bearing species in the primary Bauxite influence the occurrence of Sc in bauxite residues. In karstic bauxites, underlying carbonate rocks can work as a pH-barrier and stabilize Sc. This prevents the Sc from being mobilized and removed during bauxitization. Hence, karstic bauxites are more prone to show a Sc enrichment than lateritic bauxites. Reducing conditions during bauxitization support the incorporation of Sc into clay minerals such as chamosite, which can dissolve and reprecipitate during Bayer processing causing Sc to be redistributed and primarily adsorb onto mineral surfaces in the bauxite residue. Oxidizing conditions support the incorporation of Sc into the crystal lattice of Fe-oxides and hydroxides, which are not affected in the Bayer process. The genetic history of the bauxite is therefore the major influential factor for the Sc occurrence in bauxite residues. KW - Sc recovery KW - Scandium KW - Bauxite Residue KW - Red Mud KW - XANES PY - 2021 DO - https://doi.org/10.1016/j.apgeochem.2021.104898 SN - 0883-2927 VL - 126 SP - 104898 PB - Elsevier Ltd. AN - OPUS4-52123 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Herzel, Hannes A1 - Stemann, J. A1 - Simon, Sebastian A1 - Adam, Christian T1 - Comparison of thermochemical treatment of sewage sludge ash with sodium sulphate in laboratory-scale and pilot-scale experiments JF - International Journal of Environmental Science and Technology N2 - There is an ongoing debate on European scale concerning the criticality of phosphorus. In Switzerland and Germany, phosphorus recovery from phosphorus-rich waste streams will become obligatory. Sewage sludge ash is rich in phosphorus and may become an important secondary feedstock. Thermochemical treatment of sewage sludge ash with sodium sulphate under reducing conditions was shown to remove heavy metals from the solid product and produce the fully plant available crystalline phase CaNaPO4. Pilot-scale experiments in a rotary kiln were carried out at temperatures between 750 and 1000 °C and were compared to laboratory-scale experiments with crucibles. Process upscaling was successfully demonstrated but a series of differences were noticed: In comparison to laboratory-scale, solubility of phosphorus in samples from pilot-scale experiments was lower at all chosen treatment temperatures because of shorter retention time and incomplete decomposition of sodium sulphate. X-ray diffraction analysis revealed remaining phase fractions of whitlockite (Ca3-x(Mg,Fe)x(PO4)2) and sodium sulphate from the starting materials in products and thus indicated incomplete reaction. In contrast to the results of laboratory-scale experiments, the crystalline phase CaNaPO4 was clearly absent in the products from the rotary kiln but instead a Mg-bearing phase (Ca,Mg)NaPO4 was formed. Laboratory-scale experiments confirmed (Ca,Mg)NaPO4 is an intermediate phase between whitlockite and CaNaPO4. However, both crystalline phases are characterized by high plant availability. It was shown that heavy metal removal increased at higher temperatures whereas solubility and thus plant availability of phosphorus already reached its maxima at temperatures of 950 °C in pilot-scale and 875 °C in laboratory-scale experiments. KW - Crystalline phase identification KW - Heavy metal removal KW - Phosphorus availability KW - Process upscaling KW - Recovery KW - Rhenanite PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-524084 DO - https://doi.org/10.1007/s13762-021-03252-y VL - 19 IS - 3 SP - 1997 EP - 2006 PB - Springer AN - OPUS4-52408 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -