TY - CONF A1 - Weimann, Karin A1 - Adam, Christian A1 - Schulz, T. A1 - Linsz, E. T1 - Environmental evaluation of different ways to produce recycled concrete aggregates N2 - Due to the great quantities of construction and demolition waste in Europe, the reuse of building material waste as secondary raw materials is of particular importance. A recycling of building materials can meet the requirements of sustainability in several aspects: the extended time availability of primary raw materials and the related protection of natural resources as well as the saving of landfill sites. In recent years sulphates originating from gypsum in secondary building materials, made of construction and demolition waste, received growing attention. Sulphates are unwanted in secondary building materials for concrete production as well as for other use e.g. in unbounded layers. The content of gypsum resp. sulphates in secondary aggregates can be reduced by different methods. Depending on the type of material different steps for selective dismantling can be used to separate gypsum containing residues from concrete rubble. Furthermore some steps for the processing of building rubble are suitable for the reduction of sulphates in the produced aggregates. An environmental evaluation of different ways for the production of recycled concrete aggregates was performed with regard to a reduction of sulphates in the secondary building material. The use of techniques for selective dismantling was environmentally advantegous for the deconstruction of three investigated model houses. T2 - SUM2014 - 2nd Symposium on urban mining CY - Bergamo, Italy DA - 19.05.2014 KW - Recycling KW - Concrete aggregates KW - Building waste KW - Construction PY - 2014 SN - 9788862650311 SP - Session C 6, 1 EP - 8 AN - OPUS4-30825 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Adam, Christian T1 - Das Potential Deutscher Klärschlammaschen für die Wertstoffrückgewinnung T2 - VDI Fachkonferenz Klärschlammbehandlung CY - Berlin, Germany DA - 2012-09-26 PY - 2012 AN - OPUS4-26589 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Adam, Christian A1 - Brenneis, Rudolf A1 - Adamczyk, Burkart A1 - Simon, Franz-Georg T1 - Recycling of waste materials by thermochemical treatment T2 - ISWA World congress 2010 - Urban development and sustainbility - a major challenge for waste management in the 21st century CY - Hamburg, Germany DA - 2010-11-15 KW - thermochemical substance separation KW - Thermodynamics KW - Thermochemistry PY - 2010 SP - 1 EP - 10(?) AN - OPUS4-22467 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Weimann, Karin A1 - Adam, Christian T1 - Ökobilanzielle Bewertungen von Abbruch- und Aufbereitungsverfahren als Grundlage für ein optimiertes Bauschuttrecycling N2 - Prinzipien der Nachhaltigkeit spielen sowohl in Deutschland als auch weltweit zunehmend eine wichtige Rolle. Neben dem Bestreben nach einer Reduzierung des Energieverbrauchs gehört in diesem Zusammenhang auch die Weiterverwendung bzw, Verwertung von Reststoffen und Abfallen zu den wichtigsten Themenbereichen. Baurestmassen sind dabei aufgrund der großen Massenströme von besonderer Bedeutung. T2 - 18. Ibausil - Internationale Baustofftagung CY - Weimar, Germany DA - 12.09.2012 KW - Bauschuttaufbereitung KW - Abbruch KW - Ökobilanzielle Bewertung KW - RC-Beton KW - Gips PY - 2012 SN - 978-3-00-034075-8 VL - 2 IS - 3.07 SP - 2-1042 EP - 2-1049 AN - OPUS4-26606 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Adam, Christian T1 - Eine nachhaltige Strategie zur Nutzung des Phosphors im Klärschlamm - Ergebnisse aus dem EU-Projekt SUSAN T2 - Internationales Klärschlamm-Symposium, Wege einer verantwortungsvollen Klärschlammentsorgung CY - Fürstenfeldbruck, Germany DA - 2008-06-30 PY - 2008 AN - OPUS4-17695 LA - deu 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 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 - CONF A1 - Adam, Christian A1 - Schraut, Katharina A1 - Adamczyk, Burkart A1 - Weimann, Karin A1 - Gluth, Gregor T1 - Erzeugung klimaschonender Bindemittel als Alternativen zu Zement durch thermochemische Behandlung von mineralischen Nebenprodukten und Abfällen N2 - Die Zementindustrie erzeugt etwa 6-7% der globalen CO2-Emissionen und steht damit als Industriezweig vor dem Hintergrund einer anvisierten Klimaneutralität vor gewaltigen Herausforderungen. Der Prozess der Klinkerherstellung wurde über die vergangenen Jahrzehnte bereits kontinuierlich optimiert. Seit 1990 ist es der deutschen Zementindustrie gelungen, die spezifischen CO2-Emissionen der Zementproduktion u. a. durch den Einsatz alternativer, nicht fossiler Brennstoffe und durch Absenkung des Klinkergehalts im Zement um 20 % zu senken. Weitere konventionelle Minderungsstrategien versprechen jedoch nur noch wenig zusätzliche Reduktion. Im Falle des Portlandklinkers besteht die Schwierigkeit darin, dass zwei Drittel der CO2-Emissionen rohstoffbedingt durch die Entsäuerung des Kalksteins (CaCO3) anfallen, die durch die beschriebenen Maßnahmen nicht weiter abgesenkt werden können. Vielmehr wird es erforderlich sein, noch zu entwickelnde oder zu optimierende Technologien anzuwenden und ggf. alle relevanten Ebenen wie Produktion, Weiterverarbeitung und Anwendung von Zement und Beton neu zu denken. Neben technologischen Ansätzen zur CO2-Abscheidung mit nachfolgender langfristiger Speicherung (Carbon Capture and Storage – CCS) oder Verwertung (Carbon Capture and Utilisation – CCU) werden auch alternative Rohstoffe für die Zementproduktion und alternative Bindemittel in Betracht zu ziehen sein. T2 - Berliner Konferenz Mineralische Nebenprodukte und Abfälle CY - Berlin, Germany DA - 25.04.2022 KW - Zement KW - Sekundärrohstoff PY - 2022 SN - 978-3-944310-58-9 SP - 372 EP - 385 PB - TK-Verlag CY - Neuruppin AN - OPUS4-54737 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Smol, M. A1 - Adam, Christian A1 - Kugler, Stefan T1 - Thermochemical Treatment of Sewage Sludge Ash (SSA)—Potential and Perspective in Poland N2 - Phosphorus (P) recovery from sewage sludge ash (SSA) is one of the most promising approaches of phosphate rock substitution in mineral fertilizers and might be a sustainable way to secure supply of this raw material in the future. In the current investigation, the process of thermochemical treatment of SSA was applied to SSA coming from selected mono-incineration plants of municipal sewage sludge in Poland (Cracow, Gdansk, Gdynia, Lodz, Kielce and Szczecin). The Polish SSA was thermochemically converted in the presence of sodium (Na) additives and a reducing agent (dried sewage sludge) to obtain secondary raw materials for the production of marketable P fertilizers. The process had a positive impact on the bioavailability of phosphorus and reduced the content of heavy metals in the obtained products. The P solubility in neutral Ammonium citrate, an indicator of its bioavailability, was significantly raised from 19.7–45.7% in the raw ashes and 76.5–100% in the thermochemically treated SSA. The content of nutrients in the recyclates was in the range of 15.7–19.2% P2O5, 10.8–14.2% CaO, 3.5–5.4% Na2O, 2.6–3.6% MgO and 0.9–1.3% K2O. The produced fertilizer raw materials meet the Polish norms for trace elements covered by the legislation: the content of lead was in the range 10.2–73.1 mg/kg, arsenic 4.8–22.7 mg/kg, Cadmium 0.9–2.8 mg/kg and mercury <0.05 mg/kg. Thus, these products could be potentially directly used for fertilizer production. This work also includes an analysis of the possibilities of using ashes for fertilizer purposes in Poland, based on the assumptions indicated in the adopted strategic and planning documents regarding waste management and fertilizer production. KW - Sewage Sludge Ashes KW - Critical raw materials KW - Phosphorus KW - Fertilizer KW - Sewage Sludge PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-514468 DO - https://doi.org/10.3390/en13205461 VL - 13 IS - 20 SP - 5461 AN - OPUS4-51446 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 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 - TY - JOUR A1 - Weimann, Karin A1 - Adam, Christian A1 - Buchert, M. A1 - Sutter, J. T1 - Environmental Evaluation of Gypsum Plasterboard Recycling 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 -