TY - CHAP A1 - Fieber, Andreas T1 - Gemeinde Pfaffing. Nachhaltigkeit im Fokus: Ein Beispiel für kommunales Engagement in Pfaffing. T2 - Wir schaffen Zukunft. Standort Deutschland - Nachhaltig erfolgreich. KW - Kommunaler Nachhaltigkeitsbericht KW - Kommune KW - Nachhaltigkeitsberichterstattung KW - Kommunen KW - Sustainable Development Goals Y1 - 2025 U6 - https://doi.org/10.15358/9783800676705 SP - 114 EP - 122 PB - Verlag Franz Vahlen GmbH CY - München ER - TY - GEN A1 - Lüken, Jan-Diederich A1 - Jakob, Schäuble T1 - Wo steht die Circular Economy? BT - Anregungen für die amtliche Statistik zur Messung kreislaufwirtschaftlicher Aktivitäten. N2 - Beim Thema Kreislaufwirtschaft besteht vermutlich eine Diskrepanz zwischen den Messungen der amtlichen Statistik und den realen ökonomischen Entwicklungen. Europaweit überwacht Eurostat beispielsweise die Entwicklung der Circular Economy anhand materialbezogener Indikatoren. Diese zeigen für die letzten Jahre zwar leichte Aufwärtstrends – etwa bei der Ressourcenproduktivität, der Öko-Effizienz (Abfallintensität) und der Circular Material Use Rate (CMUR). Doch Wachstumsraten liegen einerseits deutlich unter dem erforderlichen Niveau, um die erklärten Ziele der EU zu erreichen. So soll die CMUR bis 2030 auf 22,4 % steigen; bislang liegt sie in der EU bei knapp unter 12 % (Stand: 2023), 2010 waren es 10,7%. Auch andere kreislaufwirtschaftliche Indikatoren zeigen für die letzten Jahre bestenfalls eine moderate zirkuläre Performance, bei manchen – wie beim Verpackungsmüll – sogar eine negative. Andererseits wächst die „Circular Economy“ als Narrativ. So zeigt Google Ngrams eine Vervielfachung der Nennungen des Themas in veröffentlichten Büchern in den Jahren 2015 bis 2020. Google Trends und Web of Science zeigen für den Suchbegriff „Circular Economy“ ähnliche Ergebnisse. Die Kreislaufwirtschaft ist zudem Kernbestandteil zahlreicher europäischer Regulierungsprojekte, von denen der Green Deal und der Industrial Clean Deal die prominentesten sind. In diesem Jahr wurde die nationale Kreislaufwirtschaftsstrategie in Deutschland veröffentlicht. Bayern verfolgt bereits seit 2024 eine eigene Strategie. Vermutlich gibt die amtliche Statistik den Stand und die Entwicklung der Kreislaufwirtschaft nicht vollständig wieder. Offizielle Daten erfassen die Kreislaufwirtschaft im klassischen Sinne, also als Abfall-, Verwertungs- und Materialströme. Um sie jedoch umfassend zu vermessen, müssten auch betriebliche zirkuläre Aktivitäten durch Indikatoren erfasst werden, die R-Strategien wie Redistribution, Refurbishment und Remanufacturing abbilden – also Strategien, wie sie etwa vom UN Environment Programme definiert wurden. Eine solche Erweiterung könnte dazu beitragen, den Status quo der Kreislaufwirtschaft als zentrales klimapolitisches Instrument präziser zu bestimmen. Auf unserem Poster geben wir Anregungen zur Weiterentwicklung der amtlichen Statistik, die auf Erkenntnissen mehrerer Unternehmensbefragungen mit kleineren Stichproben (jeweils n ≤ 150) beruhen. Die Umfragen wurden zwischen 2023 und 2025 durchgeführt. Eine Befragung wurde mithilfe persönlich geführter, strukturierter Interviews erhoben, die anderen Umfragen wurden mithilfe einer Online-Befragung durchgeführt. In den Umfragen wurden unter anderem Konzepte wie kreislaufwirtschaftliche Strategien, Barrieren und Treiber sowie Status und Orientierung gegenüber der Circular Economy untersucht. Y1 - 2025 ER - TY - CHAP A1 - Klaas, Lena A1 - Eltayeb, Asmaa A1 - Kriechbaumer, Dorottya A1 - Roeb, Martin A1 - Sattler, Christian T1 - \(Ca_{1-x} Sr_x MnO_{3-\delta}\) granules, pellets, foams: Influence of fabrication conditions and microstructure on oxidation kinetics T2 - Solid State Ionics N2 - Microstructure and oxidation kinetics are closely intertwined factors that significantly influence the behavior of materials in oxidative environments. This relationship is of particular importance for redox materials such as \(Ca_{1-x} Sr_x MnO_{3-\delta}\), where reversible oxygen ions exchange and oxidation state shifts are key to their functionality. In the first study, scanning electron microscope (SEM) was used to examine how varying Sr content affects the morphology and microstructure of \(Ca_{1-x} Sr_x MnO_{3-\delta}\) powder compositions. The results indicate that increasing Sr content leads to smaller particle sizes and improved particle size homogeneity. Granules with Sr concentrations ranging from 0 % to 40 % exhibit notable changes in morphology. However, the microporosity and d50 vary slightly across the samples in a non-monotonic manner, with no clear trend emerging with respect to Sr concentration. The second study investigates how macrostructural forms, such as foams and pellets, impact oxidation kinetics in \(Ca_{0.8} Sr_{0.2} MnO_{3-\delta}\). Parameters including particle size distribution of the raw material, overall microporosity, and structural characteristics of these macrostructures were analyzed for their effect on oxidation rates. Findings reveal that macrostructural configuration, alongside microstructural features like microporosity, significantly impacts oxidation kinetics. These studies collectively underscore the critical relationship between dopant concentration, microstructural characteristics, and structural morphology in determining the oxidative behavior of \(Ca_{1-x} Sr_x MnO_{3-\delta}\), providing key insights into optimizing material performance in redox environments. KW - Oxidation kinetics KW - Thermochemical cycles KW - Perovskites KW - Oxidation kinetics KW - Thermochemistry Y1 - 2025 U6 - https://doi.org/10.1016/j.ssi.2025.116803 IS - 422/4 SP - 116803 EP - 116816 PB - Elsevier CY - New York ER - TY - CHAP A1 - Kriechbaumer, Dorottya A1 - Budama, Vishnu A1 - Roeb, Martin A1 - Sattler, Christian T1 - Fuels – Hydrogen – Hydrogen Production | Thermochemical T2 - Encyclopedia of Electrochemical Power Sources (Second Edition) N2 - Green hydrogen is expected to play a major role in the energy mix of the future as it is not only an important feedstock for chemical production but also an energy carrier and fuel. For the transition from fossil routes to green production new, sustainable technologies are needed. Solar thermal energy can be directly utilized for hydrogen production without electrification via thermochemical cycles. Several thousands of cycles have already been investigated, the main types utilize redox materials with phase change properties, materials with non-stoichiometric behavior and sulfur-based cycles. This article gives an overview on the different classes of thermochemical cycles, their state of development, economics and their possibilities for a future industrial application. KW - Hydogen Production KW - Thermochemical cycles KW - Wasserstoffgewinnung KW - Thermochemisches Verfahren Y1 - 2025 U6 - https://doi.org/10.1016/B978-0-323-96022-9.00006-2 IS - Vol. 6 SP - 278 EP - 287 PB - Elsevier CY - New York ET - 2. ER - TY - JOUR A1 - Mühlböck, Kajetan A1 - Völkl, Johannes T1 - Einsatz von Sauerstoff aus der Wasserelektrolyse für chemische Synthesen JF - Chemie Ingenieur Technik N2 - Wasserstoff aus erneuerbaren Quellen ist ein zentraler Baustein zur Erreichung der Klimaziele, wobei die Wasserelektrolyse eine Schlüsseltechnologie darstellt. Dabei entsteht Sauerstoff als Koppelprodukt, das bereits in verschiedenen Anwendungen genutzt wird. Diese Studie bewertet das techno-ökonomische Potenzial der Nutzung von Elektrolysesauerstoff für die Synthese von Ethylenoxid (EO) und Vinylacetatmonomer (VAM). Abhängig vom Strompreis können die Produktionskosten für Wasserstoff um6–12 % gesenkt werden, wenn Sauerstoff zu Marktpreisen verkauft wird. Die Herstellungskosten von EO und VAM können um bis zu 4,5 % reduziert werden, sofern Sauerstoff kostenfrei bereitgestellt wird. Die Integration in industrielle Cluster ermöglicht Synergien für die Nutzung von Wasserstoff und Sauerstoff. KW - Luftzerlegung KW - Sauerstoffnutzung aus Elektrolyse KW - Techno-ökonomische Untersuchung KW - Wasserelektrolyse KW - Wasserstoffwirtschaft Y1 - 2025 U6 - https://doi.org/10.1002/cite.202400138 VL - 97 IS - 5 SP - 536 EP - 548 PB - Wiley-VCH Verlag GmbH & Co. KGaA CY - Weinheim ER - TY - CHAP A1 - Schwarz, Benedikt A1 - Lindner, Johannes T1 - Automated Process Optimization in Mixing with Adaptive and Dynamic Mixing Modes T2 - PARTEC 2025 N2 - Mixing plays a crucial role in industry, for e.g., fine and petrochemicals, food, pharmaceuticals, and mineral processing. The selection of the stirrer is based on the desired flow pattern and the rheological properties of the material being processed. A change in the mixing task or a significant shift in material properties during the process can lead to decreased efficiency, longer mixing times, or poorer mixing quality. To address the need for handling various tasks across a wide range of applications with the same mixer, a multi-purpose mixer with adjustable tools was developed. It consists of a coaxial stirrer with an inner and an outer stirrer. The blades of the inner stirrer can be changed in inclination during the process. This allows different tasks, such as dispersion, aeration, and suspension, to be performed efficiently in succession without the need for tool changes. Additionally, the process parameters can be dynamically changed to compensate for changes in the process. Energy input into the fluid serves as a key parameter to quantify the quality of a dispersion process. The three independent actuators can be used to achieve the best energy input. To identify the optimal settings, a control algorithm called the "automated design of experience" was developed. This algorithm adjusts the speed of the main and coaxial stirrers and the blade angle in a sequential manner, evaluating whether these changes lead to improved or worsened energy input. It is hence possible to determine optimum mixing parameters in an automated way. KW - Dynamic Mixing Y1 - 2025 ER - TY - GEN A1 - Schwarz, Benedikt A1 - Lindner, Johannes T1 - Variable volume flows in a hydrocyclone by changing the inlet geometry during the process T2 - PARTEC 2025 N2 - Motivation: Hydrocyclones are designed for a specific operating point but react badly to a change in operating conditions. Reducing the flow rate results in lower centrifugal forces and hence separation efficiency. Increasing the flow rate increases the pressure loss, while the separation efficiency suffers from increased turbulence. It is also not possible to react to modifications of the material or liquid phase to be separated. The aim of the present development is to create a cyclone that can react to variable operating parameters to keep the separation efficiency at a high level. Material & Methodology: Good separation in cyclones requires a stable formation of the secondary vortex, which can be characterized by high tangential flow velocity (Schubert 2003). By implementing a variable cross-section in the inlet channel, the feeding velocity into the cyclone can be kept constant at changing flow rates to maintain the secondary vortex and keep comparable separation efficiency and pressure loss. An inline turbidity measurement at the upstream outlet can be used to monitor dynamically the separation efficiency. The variable cross-section area can be controlled depending on the fluctuating volume flow or on a specific outlet concentration based on the measured turbidity. Experiments showed that operating the system at a constant pressure loss improves the separation efficiency despite a reduction of the volume flow. Efficient separation at different or even fluctuating volume flow is hence possible. KW - Mixing Y1 - 2025 ER - TY - CHAP A1 - Schwarz, Benedikt A1 - Lindner, Johannes A. ED - Dechema, T1 - Automatisierte Prozessoptimierung durch einen adaptiven, dynamischen Mischer T2 - Jahrestreffen der DECHEMA-Fachgruppen Extraktion und Mischvorgänge Y1 - 2023 ER - TY - JOUR A1 - Schwarz, Benedikt A1 - Kniele, H. A1 - Lindner, Johannes T1 - Automated Process Optimization in a Novel TripleShaft Mixer with Adaptive Mixing Modes JF - Chemie Ingenieur Technik N2 - A novel multi-purpose mixer was set up, which allows the change of the blade angle during the process and provides aflow field with respect to the needs of the mixing task. It features as well as a coaxial stirrer for highly viscous liquids andhence has three degrees of freedom. The stirrer considers the integration and validation of an optimization strategy forthe autonomous identification of an optimum operating point based on automated tests. The validation was conducted ina mixing process with several process input parameters, which is commonly used in industrial applications. The powerdraw of the main stirrer was used as a optimization parameter, representing the power used for dispersing. The speedand direction of the main and secondary stirrers, respectively, as well as the angle of the stirrer blades, were used as inputprocesses. The proposed control scheme automatically identifies and corrects drops in energy dissipation rates. KW - Mixing KW - Optimal operation KW - Reinforcement learning KW - Self-optimization Y1 - 2025 U6 - https://doi.org/10.1002/cite.70060 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Schwarz, Benedikt A1 - Krause, Peter A1 - Lindner, Johannes T1 - A Dynamic Hydrocyclone Adapting to Different Operating Points by Changing the Inlet Area JF - Chemical Engineering and Technology N2 - In this study, a novel hydrocyclone design was developed featuring a variable inlet geometry, which enables adjustment of the inlet area during operation. This allows control over the flow velocity within the cyclone, thereby maintaining a constant tangential velocity despite changes in volumetric flow rate. The prototype demonstrated a constant separation efficiency across a volumetric flow range spanning a factor of two between its minimum and maximum capacities. Two control strategies were investigated: operation at constant pressure drop and operation at constant inlet velocity, both under varying flow rates and inlet geometries. To initially examine the influence of key parameters, hydrocyclones with fixed geometries were fabricated using rapid prototyping and employed in experimental trials. These findings informed the subsequent development and construction of a dynamically adaptive steel prototype capable of dynamic geometrically adjustment. KW - dynamic hydrocyclone KW - particle separation KW - solid–liquid separation Y1 - 2026 U6 - https://doi.org/10.1002/ceat.70154 PB - Wiley-VCH CY - Weinheim ER - TY - GEN A1 - van den Berg, Gregor A1 - Lindner, Johannes T1 - Coating of Particles in Pneumatic Conveying N2 - Coating is an important process in the chemical, food and pharmaceutical industry for applying flow agents, adding colorants, applying a protective layer against humidity, for the selective release of the contents or applying a flavor layer to goods. This is usually done in a fluidized bed (Wurster coater) or a coating drum. Pneumatic conveying systems are usually already installed for conveying particulate media, for example between process steps or the filling. In pneumatic conveying, the fluidized state of the Wurster Coater is already present. The basic idea of the current project is to implement the coating step directly in the pneumatic conveying system. Experimental approach: The coating tests were carried out using a vacuum system. For this purpose, various coating chambers with different nozzle arrangements were printed using a rapid prototyper. The nozzles used were also printed in-house and adapted to the requirements. Particles with a diameter of 3 mm were used for the tests and sprayed with a common protective coating as well as blue dye. The particles were heated to 120°C in order to supply the necessary heat to evaporate the solvent. Images of the coated particles were taken and evaluated with ImageJ to analyze the coating result. The amount of coating delivered changes the coating layer linearly as expected. The tests showed that it is possible to coat particles during pneumatic conveying. A comparison with coating in a Wurster coater showed that the amount of overspray is higher than in a Wurster coater, leading a lower efficiency in the coating step in pneumatic conveying though. KW - Coating; pneumatic conveying; two-fluid nozzles; rapid prototyping; additive manufacturing nozzles; in-line particle coating Y1 - 2026 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:861-opus4-31678 ER -