Person: Lehmann, Christian
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Veröffentlichung Urban Mining(2016) Bolland, Til; Keßler, Hermann; Kosmol, Jan; Lehmann, Christian; Müller, FelixEine ambitionierte Kreislaufwirtschaft berücksichtigt alle Materialflüsse entlang der Wertschöpfungskette von der Rohstoffgewinnung bis hin zur Abfallbewirtschaftung. Dabei stellt sich eine große Herausforderung, die noch nicht angemessen in die Kreislaufwirtschaftspolitik integriert ist: Die starke, zeitabhängige Dynamik, mit der sich Materialbestände verändern. Sie wird durch die Verweilzeiten langlebiger Güter angetrieben. Deutschland hat bereits ein enormes Vermögen angehäuft - in Form von Bauwerken, Infrastrukturen und sonstigen langlebigen Gütern. Allerdings können Materialkreisläufe dieser Bauwerke und Güter mitunter erst nach einigen Jahrzehnten geschlossen werden. Um diesen Herausforderungen zu begegnen, bedarf es eines ganzheitlichen und proaktiven Ansatzes, der die als Sekundärrohstoffe nutzbaren Abfälle in Zusammenhang mit ihrer zeitlichen und räumlichen Freisetzung stellt. Die Strategie hierfür ist: Urban Mining. Die Bundesregierung erklärt in ProgRess II, dass eine Urban Mining Strategie für Deutschland erarbeitet werden wird. Im Zentrum hierfür steht die Ufoplan-Forschungsserie "Kartierung des anthropogenen Lagers". Um das Potenzial des Urban Mining auszuschöpfen, ist es notwendig, dass der Begriff einheitlich verstanden wird und inhaltlich klar ausgerichtet ist. Er soll gerade nicht die gesamte etablierte Siedlungsabfallwirtschaft beinhalten, sondern vielmehr innovative Aspekte betonen und den Fokus auf die intelligente Bewirtschaftung langlebiger Güter in der sogenannten Anthroposphäre legen, dem vom Menschen gestalteten Lebens- und Wirkungsraum. Der vorliegende Artikel stellt Grundzüge, Motivationen und Ziele des Konzepts vor.Quelle: https://www.muellundabfall.deVeröffentlichung German Informative Inventory Report 2023(Umweltbundesamt, 2023) Hausmann, Kevin; Böttcher, Christian; Butz, Wolfgang; Günther, Dirk; Feigenspan, Stefan; Mielke, Christian; Gniffke, Patrick; Schiller, Stephan; Gromke, Ulrich; Kludt, Robert; Hermann, Tim; Juhrich, Kristina; Kessler, Kai; Zheng, Jiexia; Lehmann, Christian; Döring, Ulrike; Plickert, Sebastian; Reichart, Almut; Reichel, Jens; Kotzulla, Michael; Deutschland. UmweltbundesamtThe Informative Inventory Report (IIR) is providing complementary information to Germany's air pollution inventories under the Geneva Convention on Long-range Transboundary Air Pollution of the United Nations Economic Commission for Europe (UNECE/CLRTAP) as well as the EU's National Emission Ceiling Directive (NECD). Germany's air pollution inventory includes emission data in consistent time-series ranging from 1990 (1995 for PM10, PM2.5 and 2000 for Black Carbon) to the latest reported year (2 years back) for nine air pollutants and priority heavy metals & persistent organic pollutants (POP). This report includes a comprehensive analysis of the inventory data, descriptions of methods, data sources, and carried out QA/QC activities. It follows the outline established by the latest guidelines for estimating and reporting of emission data and all data presented in this report were compiled according to those same guidelines. Quelle: BerichtVeröffentlichung Emissionsmessungen von alveolengängigem kristallinen Siliziumdioxid (RCS) an Industrieanlagen(2021) Ehrlich, Christian; Noll, Günter; Lehmann, Christian; Wusterhausen, Ernst; Remus, RainerThe potential risk from human exposure to Respirable Crystalline Silica (RCS) includes a range of serious non-malignant effects as well as lung cancer, which may occur at relatively low levels. In a previous study, investigating several industrial sectors, we found the highest emission levels of RCS in the industrial silica sand operations. 28 different sand processing facilities were examined in two complex emission measurement programmes. A two-stage cascade impactor was used to separate the particle fractions: > 10 Ìm, 10-4 Ìm and < 4 Ìm of aerodynamic diameter. The size of particles of most concern is the so-called particulate matter 4 (PM4). The analytical procedure for determining RCS in emission samples consists of using X-ray diffraction and infrared spectroscopy methods. The relationship between Total Particulate Matter (TPM), PM4 and RCS (as a percentage of PM4) was evaluated. In the case of increased Total Particulate Matter concentration in the stack gas (more than 20 mg/m3) combined with increased percentage of RCS in PM4 an exceedance of an Emission Limit Value (ELV) of 1 mg/m3 is more likely to occur. The evaluation of the emission data helped to formulate differentiated emission control requirements of the plants concerning the draft of the new German Technical Instructions on Air Quality Control (new German TA Luft). It was possible to demonstrate, under which conditions for the specific processing techniques used, emission limits for Total Particulate Matter can be used as a threshold value for the Respirable Crystalline Silica emission. If the mass fraction of quartz in the source rock to be processed is more than 20%, periodic measurements of Respirable Crystalline Silica will be necessary every three years on grinders, whereas they will be only necessary on dryers if the Total Dust concentration exceeds 5 mg/m3. © 2021, VDI Fachmedien GmBH & Co. KG. All rights reserved.Veröffentlichung A terminology for downcycling(2022) Helbig, Christoph; Huether, Jonas; Joachimsthaler, Charlotte; Lehmann, ChristianThe term downcycling is often used anecdotally to describe imperfections in recycling. However, it is rarely defined. Here, we identify six meanings of the term downcycling as used in scientific articles and reports. These encompass the material quality of reprocessed materials, target applications, product value, alloying element losses, material systems, and additional primary production. In a proposal for harmonized and more specific terminology, we define downcycling as the phenomenon of quality reduction of materials reprocessed from waste relative to their original quality. We further identify that the reduced quality can express itself thermodynamically, functionally, and economically, covering all perspectives on downcycling. Dilution, contamination, reduced demand for recycled materials, and design-related issues can cause those downcycling effects. We anticipate that this more precise terminology can help quantify downcycling, keep materials in the loop longer, use materials more often and at higher quality, and therefore assist in reducing material-related environmental impacts. © 2022 The AuthorsVeröffentlichung Urban mining(2017) Lehmann, Christian; Müller, Felix