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The SUSAN-project aimed at developing a sustainable and safe strategy for nutrient recovery from sewage sludges using thermal treatment. Mono-incineration of the sludges completely destructs the organic pollutants in a first step. The incineration residues are ashes with a high phosphorus content that still contain heavy metal compounds above the limits for agricultural use. Furthermore, phosphorus in the ashes exhibits low bioavailability - a disadvantage in farming. Therefore, in a second thermochemical step heavy metals are removed and phosphorus transferred into mineral phases available for plants. The principle of the SUSAN-project is the separation of the small heavy metals fraction from the ashes to receive a phosphorus rich product suited as raw material for fertilisers that also contains SiO2, CaO, Al2O3, Fe2O3, MgO and K2O.
The thermochemical process is based on evaporation of volatile heavy metal chlorides at 850 - 1000 °C. The sewage sludge ashes are mixed with chlorine donors such as MgCl2 or KCl, grained and treated in a thermal aggregate e.g. a rotary furnace. At the same time a transfer of non soluble P-compounds into Mineral phases available for plants takes place.
Besides technological development of the thermochemical process, the products fertilisation performance, the product design, the market for the products and the sustainability of the whole process chain are emphasised in the SUSAN-project.
In dem Projekt soll die vollständige Wiederverwertbarkeit der Schlacke und ihrer Bestandteile demonstriert werden. Dazu gehören die vollständige Rückgewinnung der metallischen Phase, die in die Edelstahlherstellung zurückgeführt werden kann, sowie die Aufwertung der mineralischen Fraktion, die ihre uneingeschränkte Verwendung als Zementzumahlstoff oder mineralischer Baustoff erlaubt. Bei geeigneter Prozessführung des elektrischen Lichtbogenofens können durch „reduzierendes Schmelzen“ die chromhaltigen Wertstoffe zusammen mit anderen Schwermetallen zu 97% in einer Metalllegierung angereichert und separiert werden. Diese kann als Rohstoff in der Metallurgie eingesetzt werden. Der Chromgehalt der mineralischen Komponte der Schlacke konnte von ca. 3% auf unter 0,1% verringert werden. Die mineralische Fraktion lässt sich durch entsprechende Zuschläge während des Schmelzbetriebes und eine anschließende Granulation der schmelzflüssigen Phase zu einem Material aufwerten, das in seiner Zusammensetzung und seinen Eigenschaften typischen Zementkomponenten entspricht und als Rohstoff in der Zementproduktion eingesetzt werden kann. Dafür müssen allerdings noch die rechtlichen Voraussetzungen geschaffen werden, da der Rohstoffeinsatz gerade im Zement strengen Auflagen unterliegt und die Zemente bestimmte Normen erfüllen müssen.
Durch die in RECARC aufgezeigte Möglichkeit der Wiederverwertung können somit Stoffkreisläufe geschlossen werden, die ansonsten zu einem Verlust wertvoller Rohstoffe führen. Vor allem die steigenden Rohstoffkosten, aber auch die immer stärker limitierten CO2-Emissionen zeigen die hohe Relevanz im Umgang mit metallurgischen Reststoffen. Eine Überführung des in RECARC demonstrierten Verfahrens in die Industrie könnte einen wichtigen Beitrag zur nachhaltigen Schonung der natürlichen Ressourcen und der Umwelt leisten.
Über das Korrosionsverhalten nichtrostender Stähle bei atmosphärischer Beanspruchung liegen umfangreiche Erfahrungen aus jahrzehntelangen praktischen Anwendungen weltweit vor. Systematische Auslagerungsversuche unter spezifischen Umgebungsbedingungen ergänzen diese Erfahrungen. Die daraus gewonnenen Daten erlauben die beanspruchungsgerechte Werkstoffauswahl. Unter vielen atmosphärischen Bedingungen sind die nichtrostenden Stähle bei freier Bewitterung, auch unter langzeit- oder dauerfeuchten Bedingungen vollständig korrosionsbeständig. Die Auswahl der nichtrostenden Stähle muss den jeweiligen Einsatzbedingungen angepasst werden, um in jedem Fall sicherzustellen, dass der passive Zustand aufrechterhalten bzw. eine erneute Passivierung unter den Einsatzbedingungen möglich ist. Störungen der Passivschichtausbildung führen zu verminderter Korrosionsbeständigkeit mit den für nichtrostende Stähle typischen örtlichen Korrosionserscheinungen. Das Merkblatt gibt Hinweise zur Werkstoffauswahl, zur Oberflächenausführung, zur Konstruktion sowie zu Verarbeitung, Nachbehandlung und Reinigung.
With Direct Laser Writing (DLW) maturing in all aspects as a manufacturing technology a toolset for quality assurance must be developed. In this work we want to introduce a first of its kind test artifact. Test artifacts are standardized 3D models with specific geometric feature to evaluate the performance of writing parameters. Test artifacts are already common in other 3D additive manufacturing technologies e.g. Selective Laser Melting. The test artifact introduced in this work was developed in particular to accommodate 1) the high geometrical resolution of DLW structures and 2) the limited possibilities to examine the resulting structure. Geometric accuracy, surface adhesion as well as confocal raman spectroscopy results were considered when evaluating the design of the test artifact. We will explain the individual features and design considerations of our DLW test artifact. The difference between two slicers, Cura and 3DPoli, and the implications on measured feature sizes and the general shape is quantified. The measured geometries are used to derive a general design guide for a specific combination of photoresist, laser power and scanning speed and to analyse the geometric accuracy of a structure produced using these guidelines.
The impact of magnetism on chemical ordering in face-centered cubic CrCoNi medium entropy alloy is studied by a combination of ab initio simulations, machine learning potentials, and Monte Carlo simulations. Large magnetic energies are revealed for some mixed L12 /L10 type ordered configurations, which are rooted in strong nearest-neighbor magnetic exchange interactions and chemical bonding among the constituent elements. There is a delicate interplay between magnetism and stability of MoPt2 and L12 /L10 type of ordering which may explain opposing experimental and theoretical findings.
The processes of hydrogen reduction of silicon and germanium chlorides under the conditions of radio-frequency (40.68 MHz) counteracted arc discharge stabilized between two rod electrodes were investigated. The main gas-phase and solid products of plasma-chemical transformations were determined.
Thermodynamic analysis of SiCl4 + H2 and GeCl4 + H2 systems was carried out. It is shown that under the implemented experimental conditions, equilibrium components of the products are established. The detected spectra of chemical activity were studied, which gave reason to assume that the molecular mechanism of the hydrogen reduction process is the main one. The impurity composition of gas-phase and solid reaction products was investigated. The possibility of single-stage production of high-purity Si and Ge mainly in the form of compact ingots, as well as high-purity chlorosilanes and trichlorogermane, was shown.
Determining a pore structure’s mechanical and chemical data on lime rendering exposed
outdoors and including masonry in the laboratory, with regard to their behaviour on moisture
transport and weathering was the objective. In search of clues for a dose-response relation -
i.e. upon a connection between the emission rate of SO2 and NOx on one hand and the degree
of damage to mainly plaster having a lime component on the other - it has been of interest to
what extent their structural characteristics including pore space are modified and so
consequently also physico-technical properties and chemical composition. For determining
corresponding criteria, a widely diversified spectrum of test methods such as to obtain data
concerning porosity and moisture transport, mechanical behaviour, and chemistry as well is
available. A description of the manufacture of plate-shaped rendering specimens with lime
putty, industrially hydrated lime and dolomitic hydrate (the last two also having a cement
admixture) and also hydraulic lime as binding agents is included. First deposition velocity and
absorption rate for SO2 were determined in laboratory tests on these materials in dry and
moist states. After their exposure on outdoor racks at six locations in the Berlin region with
differing SO2 atmospheric contents over at least 5 years, the samples of course show timedependent
modifications of chemical and physical qualities which are especially reflected in
the form of profiles of structure, strength and concentration, e.g. for sulphate. Local climatic
differences, however, partly exert a greater influence on material than emissions. Similar
investigations were performed on samples of comparable composition exposed 4 and 17
years. But the real surprise is furnished by the renderings’ behaviour depending upon
orientation and upon height at a building. Since weathering behaviour and moisture transport
(absorption, storage, release) are directly interdependent, further criteria are necessary for a
critical assessment of a plasters’ pore structure. Starting from sands, plasters were
characterized. The structural parameters were lastly influenced by the respective contents of
sand, binder and mixing water. These results and those gained from bricks naturally find their
expression in masonry sections manufactured there from, and above all in their capillary and
evaporative behaviours, and also when applying different test liquids. Summary and cited
literature is given at the end of this report.
H2Sense - Cost-effective and reliable Hydrogen Sensors for Facilitating the Safe Use of Hydrogen
(2016)
The H2SENSE (Cost-effective and reliable hydrogen sensors for facilitating the safe use of hydrogen) project promoted hydrogen primarily, but not exclusively, for its use as an alternative fuel. It brought together different stakeholders including sensor manufacturers, end-users, certification bodies and independent evaluators to ensure the optimum use of low-cost and reliable hydrogen sensors.
Project partners analysed sensor performance in real-life applications in industrial environments and identified increased requirements for sensors and for regulations, codes and standards. H2SENSE also facilitated the safe use and implementation of hydrogen as an alternative fuel by ensuring the correct use of effective hydrogen detection devices.
European scientists worked together with colleagues from the National Renewable Energy Laboratory (NREL) in Colorado, USA. They pooled their knowledge of developments in hydrogen sensor technology as well as deployment and commercialisation strategies. These benefits will be continued through trans-Atlantic inter-laboratory sensor testing programmes in which EU and US laboratories perform complementary tests and exchange results.
T cells need to adapt their cellular metabolism for effector cell differentiation. This relies on alterations in mitochondrial physiology. Which signals and molecules regulate those alterations remains unclear. We recently reported, that the mitochondrial protein TCAIM inhibits activation-induced changes in mitochondrial morphology and function and thus, CD effector T cell formation. Using conditional TCAIM knock-in (KI) and knockout (KO) mice, w now show that it also applies to CD8+ T cells and more importantly, delineate the molecular processes in mitochondria by which TCAIM controls effector cell differentiation. TCAIM KI resulted in reduced activation-induced HIF1α protein expression. Metabolomics and transcriptional data in combination with mathematical flux modeling revealed an impaired induction of anabolic pathways, especially of the mevalonate pathway and cholesterol biosynthesis in TCAIM KI CD8+ T cells. Addition of cholesterol completely rescued HIF1α protein expression, activation and proliferation of TCAIM KI CD8+ T cells. At the molecular level, TCAIM delayed activation-induced mitochondria-ER contact (MERC) formation by binding to MERC promoting proteins such as RMD3 and VDAC2. In summary, we demonstrate that TCAIM suppresses effector cell differentiation by inhibiting MERC formation, which induce HIF1α-mediated increase in cellular metabolism and cholesterol biosynthesis.
Das Projekt befasste sich mit der Suffosion in weitgestuften Erdstoffen. Dabei werden Poren- und Gefügestrukturen visualisiert und parametrisiert.
Bei der Suffosion handelt es sich um eine Form der inneren Erosion bei weitgestuften Erdstoffen, die durch Umlagerung und Abtransport feiner Sedimentteilchen im Porenraum unter dem Einfluss von Wasserströmungen hervorgerufen wird. Die Suffosion kann zu Problemen mit der Stabilität des Korngerüstes von Erdstoffen führen. Relevante Anwendungsgebiete sind z.B. im Verkehrswegebau, Hochwasserschutz und allgemeinen Erdbau zu finden. Im Rahmen des Projektes wurden solche Erosionsprozesse numerisch simuliert, um auf statistischer Grundlage Grenzzustände zu formulieren. Ziel des Projekts war es, die Erosionsprozesse numerisch zu simulieren, um auf statistischer Grundlage Grenzzustände zu formulieren.