4.4 Thermochemische Reststoffbehandlung und Wertstoffrückgewinnung
Filtern
Dokumenttyp
- Vortrag (95)
- Zeitschriftenartikel (56)
- Beitrag zu einem Tagungsband (15)
- Posterpräsentation (14)
- Buchkapitel (5)
- Tagungsband (Herausgeberschaft für den kompletten Band) (1)
- Dissertation (1)
- Forschungsbericht (1)
Schlagworte
- Recycling (26)
- Phosphor (20)
- Klärschlamm (17)
- Phosphorus (15)
- Phosphorrückgewinnung (14)
- Phosphorus recovery (14)
- Sewage sludge (12)
- Fertilizer (9)
- Klärschlammverordnung (9)
- CFK (8)
- Gichtgasschlamm (7)
- Scandium (7)
- BOFS (6)
- Environmental evaluation (6)
- Fertilzer (6)
- Hydraulic reactivity (6)
- Pyrometallurgy (6)
- Elektroofenstaub (5)
- Gypsum (5)
- Klärschlammasche (5)
- Lichtbogenofen (5)
- Portland Cement (5)
- Pyrometallurgie (5)
- Ressourcenrückgewinnung (5)
- Ringversuch (5)
- Sewage sludge ash (5)
- Tantal (5)
- Wastewater (5)
- XANES spectroscopy (5)
- Zement (5)
- Zink (5)
- Alite (4)
- Cabonfasern (4)
- Carbon Fibers (4)
- Circular economy (4)
- Diffusive Gradients in thin films (DGT) (4)
- Diffusive gradients in thin films (DGT) (4)
- Düngemittel (4)
- Dünger (4)
- Electric arc furnace dust (4)
- LD-Schlacke (4)
- Makronährstoffe (4)
- Nährstoffe (4)
- Phosphat (4)
- Red Mud (4)
- Stahlwerksschlacke (4)
- Steelmaking slag (4)
- Tantalum (4)
- X-ray absorption near-edge structure (XANES) spectroscopy (4)
- Zinc (4)
- Baustoffrecycling (3)
- Bauxite Residue (3)
- Blast furnace sludge (3)
- CDW processing (3)
- Carbonfaser (3)
- DGT (3)
- Electric Arc Furnace (3)
- Gypsum recycling (3)
- Landwirtschaft (3)
- Laser-induced breakdown spectroscopy (3)
- Leichtbau (3)
- Mantelverordnung (3)
- Phosphorus fertilizer (3)
- Recycling fertilizer (3)
- Rotschlamm (3)
- Sekundärrohstoffe (3)
- Selective chlorination (3)
- Soil (3)
- Steelmaking (3)
- Thermochemisch (3)
- X-ray diffraction (3)
- AbfKlärV (2)
- Abwasser (2)
- Abwasserbehandlung (2)
- Agronomic performance (2)
- Agronomische Effizienz (2)
- Alkalien (2)
- Aluminium (2)
- Ammonium (2)
- Analytik (2)
- AshDec (2)
- Ashdec (2)
- Bagasse (2)
- Bassanite (2)
- Building and Construction (2)
- Calcium alkali phosphate (2)
- Calcium silicate (2)
- Calcium sulfate (2)
- Carbide formation (2)
- Carbon feeding (2)
- Carbonfasern (2)
- Chromium (2)
- Clinker substitute (2)
- Combustion Ion Chromatography (2)
- Diffusive gradients in thin-films (DGT) (2)
- Filterstaub (2)
- Gypsum fiberboards and synthetic gypsum (2)
- Heavy metal removal (2)
- Infrared spectroscopy (2)
- Leaching (2)
- Leaching control mechanisms (2)
- Melting experiments (2)
- Monoverbrennung (2)
- Monoverbrennungsanlage (2)
- Nitrification inhibitor (2)
- Nutrient (2)
- P-Recyclingdünger (2)
- Per- and Polyfluoroalkyl substances (PFAS) (2)
- Phopshorus recovery (2)
- Pollutant (2)
- Raman spectroscopy (2)
- Recovery (2)
- Recycling fertiliser (2)
- Recycling fertilisers (2)
- Reduction process (2)
- Reproduzierbarkeit (2)
- SCALE (2)
- Scattering (2)
- Secondary Recources (2)
- Sewage sludge ordinance (2)
- Soil P species (2)
- Struvit (2)
- Struvite (2)
- Thermal treatment (2)
- Thermochemical treatment (2)
- Tricalcium-silicate (2)
- Tricalciumsilikat (2)
- X-ray adsorption near-edge structure (XANES) spectroscopy (2)
- XANES (2)
- Zementersatz (2)
- Zementklinker (2)
- Zinnschlacke (2)
- Zitronensäure (2)
- Abwasserreinigung (1)
- Aerodynamic levitation (1)
- Alit (1)
- Alite hydraulic reactivity (1)
- Ashes (1)
- BESSY (1)
- Bauxite residue (1)
- Bio-P-Kläranlage (1)
- Bioavailability (1)
- Bioceramics (1)
- Blast-furnace sludge (1)
- Bushveld Complex (1)
- CFRP (1)
- CaNaPO4 (1)
- Calcium carbonate (1)
- Carbonbeton (1)
- Chemical extraction (1)
- Chemical extraction methods (1)
- Chemische Löslichkeit (1)
- Chicken manure (1)
- Chicken manure ash (1)
- Chlorination (1)
- Chlorine (1)
- Chromitites (1)
- Clean steel (1)
- Co-combustion (1)
- Combustion and gasification (1)
- Controlled release fertilisers (1)
- Corrosion (1)
- Critical raw materials (1)
- Crystalline phase identification (1)
- DGT-Methode (1)
- Design of experiments (1)
- Diffusive Gradients in Thin-films (DGT) (1)
- EAF slags (1)
- Electric arc furnace (EAF) slags (1)
- Electric arc furnace slags (1)
- Elektrolichtbogenofen (1)
- Elimination (1)
- Entropy (1)
- Extraction (1)
- Extraktion (1)
- Extraktionen (1)
- Extraktionsversuche (1)
- FactSage calculations (1)
- FactSageTM calculations (1)
- Forest soils (1)
- Formation enthalpy (1)
- Forschungsförderung (1)
- Fällmittel (1)
- General Environmental Science (1)
- General Materials Science (1)
- Gesteinskörnungen (1)
- Gipsabfälle (1)
- Gipsrecycling (1)
- Gleichwertigkeit Messverfahren (1)
- Granulat (1)
- Gypsum plasterboards (1)
- Gypsum waste (1)
- Hazardous waste (1)
- Hazenite (1)
- Heat capacity (1)
- Hydration products (1)
- Hydrogen (1)
- ICP-MS (1)
- ICP-OES (1)
- In situ (1)
- In situ synchrotron x-ray diffraction (1)
- In-situ analysis (1)
- Incubated soil/fertilizer mixtures (1)
- Industrial and Manufacturing Engineering (1)
- Industrielles Abwasser (1)
- Interlaboratory comparison (1)
- Iron making (1)
- Klimaneutralität (1)
- Kläranlage (1)
- Klärschlammdüngung (1)
- Kreislaufwirtschaft (1)
- LCA (1)
- Landwirtschaftliche Klärschlammverwertung (1)
- Lead (1)
- Lebensmittelindustrie (1)
- Lightweighting (1)
- MSWI fly ash (1)
- Materials Chemistry (1)
- Mechanische Stabilität (1)
- Metals and Alloys (1)
- Microbially induced carbonate precipitation (MICP) (1)
- Multidisciplinary (1)
- Municipal sewage sludge (1)
- MySpot (1)
- Nachhaltigkeit (1)
- Nano-Fourier-transform infrared spectroscopy (1)
- Neutralammoniumcitrat (1)
- Neutralammoniumnitrat (1)
- Niobium (1)
- Nitrate (1)
- Nitrogen (1)
- On-Line Analyse (1)
- On-line analysis (1)
- Oxide melts (1)
- P sink method (1)
- P speciation (1)
- P-Recyclate (1)
- P-Rückgewinnung (1)
- P-Senken (1)
- P-efficiency (1)
- P-recovery (1)
- Passive sampling (1)
- Permeat (1)
- Perowskit (1)
- Pflanzenverfügbarkeit (1)
- Pflanzenwurzel (1)
- Phase formation (1)
- Phase transformation (1)
- Phoshpor availability (1)
- Phosphate dynamics (1)
- Phosphate extractability and availability (1)
- Phosphor-Rückgewinnung (1)
- Phosphorbestimmung (1)
- Phosphorus availability (1)
- Phosphorus elimination (1)
- Phosphorus plant-availability (1)
- Phosphorus recycling (1)
- Phosphous recovery (1)
- Photometric P determination (1)
- Plant Experiment (1)
- Plant availability (1)
- Plant growth test (1)
- Plant-availability (1)
- Plasma (1)
- Platinum (1)
- Pot experiment (1)
- Pot experiments (1)
- Process Metallurgy (1)
- Process control (1)
- Process upscaling (1)
- Push-out Test (1)
- Raman (1)
- Recovery potential (1)
- Recycled gypsum (1)
- Recycled sources (1)
- Recyclingdüngemittel (1)
- Red mud (1)
- Reduction (1)
- Reduktionsprozess (1)
- Relative agronomische Effizienz (RAE) (1)
- Renewable Energy, Sustainability and the Environment (1)
- Resource Recovery (1)
- Ressourceneffizienz (1)
- Ressourcenschonung (1)
- Retentat (1)
- Rhenanite (1)
- Ringversuch P-Gehalt in Klärschlamm (1)
- Rückgewinnung (1)
- Sc recovery (1)
- Scattering-type scanning near-field optical microscopy (s-SNOM) (1)
- Schlacke (1)
- Secondary P-fertilizer (1)
- Sekundärgipse (1)
- Sekundärrohstoff (1)
- Selective Chlorination (1)
- Sewage Sludge (1)
- Sewage Sludge Ashes (1)
- Sewage sludge ash (SSA) (1)
- Sewage sludge disposal (1)
- Sewage sludge incineration (1)
- Silicate (1)
- Silicon carbide (1)
- Spectroscopy (1)
- Stalwerksschlacke (1)
- Steelmaking residues (1)
- Strategy and Management (1)
- Sugar cane bagasse (1)
- Sugarcane bagasse (1)
- Sustainability (1)
- Synchrotron (1)
- Synchrotron radiation (1)
- Technologietransfer (1)
- Thermal analysis (1)
- Thermochemische Prozesse (1)
- Upscaling (1)
- Ureolytic bacteria (1)
- Vegetationsversuche (1)
- Versuchskampagne (1)
- Wasserstoffplasma (1)
- Waste (1)
- Waste water (1)
- Waste water treatment (1)
- Wiederholbarkeit (1)
- Wiederverwertung (1)
- Wood ash (1)
- X-ray diffraction (XRD) (1)
- X-ray spectroscopy (1)
- Zentrat (1)
- Zinc chloride (1)
- Zinnschlacken (1)
- fertilizer (1)
- infrared spectroscopy (1)
- microspectroscopy (1)
- multi scale testing (1)
- soil (1)
- thermochemische Behandlung (1)
- x-ray diffraction (1)
- Ökobilanz (1)
Organisationseinheit der BAM
- 4.4 Thermochemische Reststoffbehandlung und Wertstoffrückgewinnung (188) (entfernen)
Paper des Monats
- ja (3)
One of the key elements in the transformation towards a circular economy (CE) is providing more sustainable practices for resources and waste management. Improvement actions focused on transformation towards a CE should be targeted at all groups of materials and waste. As water is essential for human survival and well-being and plays a significant role in sustainable development (SD), the actions related to the reuse of water and the recovery of raw materials from wastewater and other water-based waste should be taken. The paper presents a proposition for a new CE model framework in the water and wastewater sector, which includes the six following actions: reduction—prevent wastewater generation in the first place by the reduction of water usage and pollution reduction at source; reclamation (removal)—an application of effective Technologies for the removal of pollutants from water and wastewater; reuse—reuse of wastewater as an alternative source of water supply (non-potable usage), recycling—recovery of water from wastewater for potable usage; recovery—recovery of resources such as nutrients and energy from water-based waste, and rethink—rethinking how to use resources to create a sustainable economy, which is `free` of waste and emissions. The novelty of the proposed CE model framework is that it presents possible ways of implementing CE principles in the water and wastewater sector, with a strong emphasis not only technological but also organisational and societal changes. Application of the proposed model may help to further transform the European economy to the CE model. Moreover, the indicated model can be significant tool supporting an assessment of local or regional progress towards CE in the water and wastewater sector and further environmental management and planning.
Hydrogen plasma treatment of iron ores or iron oxide containing wastes can be an efficient option to produce green iron e.g. for steel production. This way iron oxide is reduced to metallic iron in the liquid form by the highly reactive species that are formed in a hydrogen plasma. Hydrogen plasma can be used at the same time to remove undesired gangue elements. The presentation shows the experimental setup, shows first results of iron ore reduction by hydrogen plasma and gives an outlook for industrial application of the technology.
The challenge of the project ASHES is focused on the recycling of nutrients from residues of thermochemical processing of by-products of sugar cane industry (bagasse/straw) in Brazil to increase the energy efficiency of thermal conversion and to enable the recycling of process ashes as fertilisers. Dry lignocellulosic biomass (straw, bagasse) are combusted, gasified and subsequently combined with post-thermochemical treatment in the AshDec process to increase the plant availability of phosphorus. Different fertilizer formulations are granulated/pelletized and tested regarding their storage/handling characteristics.
Jährlich entstehen in Brasilien ca. 2 bis 10 Millionen Tonnen Aschen aus der Verbrennung von Zuckerrohrbagasse. Die Aschen enthalten schwankende Zusammensetzungen an mineralischen Nährelementen und könnten daher zu Düngezwecken verwendet werden.
Allerdings ist (i) die Nährstoffverfügbarkeit gering, (ii), die entsprechende Nährstoffzusammensetzung nicht optimal für die Nutzung der Aschen als Düngemittel für die Hauptanbaukulturen in Brasilien und (iii) weisen die Aschen aufgrund häufig schlechter Verbrennungsqualitäten hohe organische Kohlenstoffgehalte auf. Im Rahmen des Forschungsprojekts ASHES („Rückführung von Nährstoffen aus Aschen von thermochemischen Prozessen mit Bagasse bzw. Zuckerrohrstroh“), arbeiten 7 deutsche und 4 brasilianische Partner an der Optimierung der thermochemischen Verwertung von Rückständen aus der Zuckerproduktion in Brasilien, inklusive der Formulierung von optimierten Düngemischungen auf Basis der generierten Aschen. In dieser Veröffentlichung wird die Verarbeitung dieser optimierten Mischungen zu Pellets und Granulaten unter Verwendung verfügbarer regionaler Reststoffe wie Filterkuchen (Vinasse-Presskuchen) sowie Hühnertrockenkot beschrieben. Zur Untersuchung der Handlingeigenschaften wurden die produzierten Pellets und Granulate hinsichtlich ihrer mechanischen Stabilität und des Wasseraufnahmevermögens untersucht. Dafür wurden geeignete Prüfverfahren angepasst und entsprechende Versuche durchgeführt.
Calcium sulfate hemihydrate (CaSO4ᐧ0.5H2O), also known as bassanite, has been used as a precursor to produce gypsum (dihydrate, CaSO4ᐧ2H2O) for various construction and decorative purposes since prehistoric times. The main route to obtain hemihydrate is a thermal treatment of gypsum at temperatures typically between 150 °C and 200 °C to remove some of the structural water.
In this contribution, we introduce (Fig. 1) a more efficient and sustainable method (T < 100 °C) that enables the direct, rapid, and reversibly conversion of gypsum to bassanite using reusable high salinity aqueous solutions (brines with c[NaCl] > 4 M). The optimum conditions for the efficientproduction of bassanite in a short time (< 5 min) involve the use of brines with c(NaCl) > 4 M and maintaining a temperature, T > 80 °C. When the solution containing bassanite crystals is cooled down to around room temperature, eventually gypsum is formed. When the temperature is raised again to T > 80 °C, bassanite is rapidly re-precipitated. This contrasts with the typical behaviour of the bassanite phase in low salt environments.
Traditionally, hemihydrate is obtained through a solid state thermal treatment because bassanite is considered to be metastable with respect to gypsum and anhydrite in aqueous solutions, and therefore gypsum-to-bassanite conversion should not occur in water. Its very occurrence actually contradicts numerical thermodynamic predictions regarding solubility of calcium sulfate phases. By following the evolution of crystalline phases with in situ and time-resolved X-ray diffraction/scattering and Raman spectroscopy, we demonstrated that the phase stability in brines at elevated temperatures is inaccurately represented in the thermodynamic databases. Most notably for c(NaCl) > 4 M, and T > 80 °C gypsum becomes readily more soluble than bassanite, which induces the direct precipitation of the latter from gypsum. The fact that these transformations are controlled by the solution provides extensive opportunities for precise manipulation of crystal formation. Our experiments confirmed that bassanite remained the sole crystalline structure for many hours before reverting into gypsum. This property is extremely advantageous for practical processing and efficient crystal extraction in industrial scenarios.
Here, we show that calcium sulfate dihydrate (gypsum) can be directly, rapidly and reversibly converted to calcium sulfate hemihydrate (bassanite) in high salinity solutions (brines). The optimum conditions for the efficient production of bassanite in a short time (<5 min) involve the use of brines with c(NaCl) > 4 M and maintaining a temperature, T > 80 °C. When the solution containing bassanite crystals is cooled down to around room temperature, eventually gypsum is formed. When the temperature is raised again to T > 80 °C, bassanite is rapidly re-precipitated. This contrasts with the better-known behaviour of the bassanite phase in low-salt environments. In low-salinity aqueous solutions, bassanite is considered to be metastable with respect to gypsum and anhydrite, and therefore gypsum-to-bassanite conversion does not occur in pure water. Interestingly, the high-salinity transformation of gypsum-to-bassanite has been reported by many authors and used in practice for several decades, although its very occurrence actually contradicts numerical thermodynamic predictions regarding solubility of calcium sulfate phases. By following the evolution of crystalline phases with in situ and time-resolved X-ray diffraction/scattering and Raman spectroscopy, we demonstrated that the phase stability in brines at elevated temperatures was inaccurately represented in the thermodynamic databases. Most notably for c(NaCl) > 4 M, and T > 80 °C gypsum becomes readily more soluble than bassanite, which induces the direct precipitation of the latter from gypsum. The fact that these transformations are controlled by the solution provides extensive opportunities for precise manipulation of crystal formation. Our experiments confirmed that bassanite remained the sole crystalline phase for many hours before reverting into gypsum. This property is extremely advantageous for practical processing and efficient crystal extraction in industrial scenarios.
In the near future, phosphorus (P) recycling will gain importance in terms of decreasing primary resources. Sewage sludge (SSL) is an adequate secondary P-resource for P-fertilizer production but it is also a sink for heavy metals and organic pollutants. The present study is an investigation on thermochemical P-recycling of SSL. Various temperatures and amendments were tested regarding their performance to remove heavy metals and polycyclic aromatic hydrocarbons (PAH) and simultaneous increase of the plant-availability of P. The investigations were carried out on two types of SSL originating from wastewater treatment plants with chemical P-precipitation and enhanced biological P-removal, respectively. The results show that thermochemical treatment with chlorine donors is suitable to remove the majority of heavy metals and that a combination of a gaseous chlorine donor (HCl) and sodium additives leads to both high heavy metal removal and high plant availability of P. Furthermore, plant experiments Show that almost all investigated thermochemical treatments can significantly reduce the bioavailability and plant uptake of heavy metals. Furthermore, PAHs are secondarily formed during low-temperature treatments (400–500 ° ), but can be significantly reduced by using sodium carbonate as an additive.
Phosphorus (P) resource availability and quality is declining and recycling P-fertilizers from waste materials are becoming increasingly important. One important secondary P resource is sewage sludge (SSL) where P is often bound as aluminum phosphate (Al-P), iron phosphate (Fe-P) and polyphosphate (poly-P), respectively. Thermal treatment in different ways is a promising way in P recycling to produce highly plant-available P-fertilizers. To investigate mechanisms behind transformation of hardly available P-species toward plant-available P forms we treated a model SSL containing different kinds of defined P sources by low-temperature conversion (LTC) at 500 °C and subsequent thermochemical treatment of the LTC product with Na additives (TCT) at 950 °C, respectively. Pot experiments with ryegrass were carried out to determine the plant availability of P of the different treatments. The poly-P (here pyrophosphates) based fertilizers had a very high plant availability after both thermal treatments. During LTC treatment the plant availability of the Fe-P and Al-P variants increased because of the Formation of Fe(II) phosphates and/or pyro-/polyphosphates. Especially the formation of Al-polyphosphate shows a high plant availability. The subsequent TCT further increased strongly the plant availability of the Fe-P variants because of the formation of highly plant-available CaNaPO4. Thus, a direct TCT without prior LTC probably also produce CaNaPO4 and is recommended for Fe-P based SSL. However, a molar Ca/P ratio of 1 in the fertilizer is favorable for CaNaPO4 formation. Thus, the knowledge on the source of primary P in SSL is essential for choosing the accurate thermal treatment method to produce highly plant-available P-fertilizers from SSL.
Phosphorus (P) recycling from sewage sludge for agricultural needs has to meet requirements for agricultural implementation, such as short and long-term P-plant-availability under field conditions. Field experiments often bring no evaluable results, because agricultural soils got a high potential of P-supply even if they are classified as low in P-supply according to the CAL extraction method. The present study presents a possible way to investigate the P-plant-availability of P-recycling-fertilizers under field-like conditions. The plant experiments are firstly performed in small Mitscherlich pots in growth chambers and subsequently in containers with a high soil volume of 170 kg under greenhouse conditions, in which plants can grow until ripening. The tested P-recycling fertilizers were produced from sewage sludge in a large-scale thermal process. It was a two-step treatment process performed with a pyrolysis of sewage sludge at 550°C (SSC-550) and a subsequent thermochemical post-treatment at 950°C with Na2SO4 (SSA-Na) and HCl + Na2SO4 (SSA-HCl/Na) as additives. The results show, that the P-recycling-products from pyrolysis got an adequate long-term but a 65% lower short-term P-plant-availability compared to triple superphosphate. SSA-Na and SSA-HCl/Na show both a high short and longterm P-plant-availability comparable to triple-superphosphate. This can be explained by their highly plant-available P-compound CaNaPO4.
Optimierung eines pyrometallurgischen Tantal- und Niob- Recyclingprozesses mithilfe von On-Line LIBS
(2018)
Die Entwicklung von Hochleistungselektronik zu immer kleineren Bauformen ohne Leistungseinbußen ist ohne den Einsatz von Technologiemetallen wie Niob und Tantal heute praktisch nicht mehr realisierbar. Besonders in technischen Geräten wie Smartphones und Tablets sind Tantal- und Niobkondensatoren aufgrund ihrer hohen Leistungsdichten bereits unverzichtbar geworden. Für die nachhaltige Produktion von Elektronik stellt jedoch vor allem das Tantalerz Coltan als sogenanntes „conflict mineral” ein großes Problem dar.
Um den Wirtschaftsstandort Europa unabhängiger von Primärrohstoffimporten aus Krisenregionen zu machen, ist die Entwicklung von effizienten Recyclingverfahren heute wichtiger denn je. An der Bundesanstalt für Materialforschung und -prüfung (BAM) findet daher zurzeit die Optimierung eines pyrometallurgischen Industrieprozesses zur Niob- und Tantalrückgewinnung statt, welchem hauptsächlich niedrigkonzentrierte metallurgische Rückstände aus der Tantal- und Niob- bzw. der Zinngewinnung als Einsatzstoffe dienen.
Zu diesem Zweck werden im kleintechnischen Lichtbogenofen der BAM (480 kVA, max. Materialdurchsatz ca. 150 kg/h) Versuche mit einem neuen innovativen Messgerät durchgeführt, welches eine On-Line Analyse von Hochtemperaturprozessen ermöglicht. Der eingesetzte Prototyp nutzt das Verfahren der laserinduzierten Plasmaspektroskopie (LIBS), um die chemische Zusammensetzung der Schlackephase noch im Schmelzbad und während eines Schlackeabgusses zu bestimmen. Nach einer Kalibrierung auf das vorliegende Stoffsystem ermöglicht dieser On-Line-LIBS Prototyp der BAM daher eine in-situ Bestimmung der Elementverteilung in der Schmelze. Die hier gewonnenen Daten sollen helfen, die aktuelle Prozessführung zu verbessern und die Tantal- und Niobausbeute noch weiter zu erhöhen.