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The classification of incineration bottom ash (IBA) as hazardous or non-hazardous according to ecotoxic hazard property HP14 is still under debate. In this context, only the compounds of Zn and Cu with the hazard statement code H410 are of relevance. With an approach based on the grouping of substances, it was shown that such substances are either readily water-soluble or slightly and sparingly soluble. The concentrations of readily soluble Cu and Zn compounds in IBA are far below the cut-off value of 0.1%. Slightly and sparingly soluble Zn and Cu compounds could be quantified in the first fraction of a four-step sequential extraction procedure. With the results from the complete sequence, the dimensionless synthesis toxicity index (STI) was calculated and was in the range of 494 to 1218 for the four investigated IBA samples. It was concluded that IBA can usually be classified as non-hazardous.
Half of the global material consumption is mineral material. The circularity is still low so that enhanced use of secondary building material is required to close loops. Three different secondary building materials are discussed based on exemplary research results: construction and demolition waste (C&D waste), soil-like material and incineration bottom ash (IBA). Focus was laid on the environmental compatibility of the materials examined mainly by standardized leaching tests. C&D waste was investigated after a wet treatment using a jigging machine, soil-like material and IBA were characterized with respect to their material composition. The environmental compatibility in particular was studied using standard leaching tests (batch tests and column tests). It was concluded that soil-like material can mostly be utilized even when the precautionary limit values set are exceeded by a factor of less than 2. For C&D waste the fine fraction below 2 mm and the content of brick material is problematic. IBA fulfills quality level HMVA-2 following German regulation. Higher quality levels of utilization might be achievable with better treatment technologies.
Die Thermische Abfallbehandlung in Abfallverbrennungsanlagen sorgt für eine Inertisierung des Restmülls bei gleichzeitiger Minimierung von abgas- und abwasserseitigen Emissionen. Da der Großteil der Rückstände in verwertbare Sekundärprodukte überführt wird, fördert die thermische Abfallbehandlung die Verwirklichung einer Circular Economy in Europa.
In den Rückständen thermischer Verfahren sind als Folge des Verbrennungsprozesses Metalle sowohl in elementarer wie auch in chemisch gebundener Form enthalten. Früher wurde Eisenschrott vor allem deshalb mit Magneten abgetrennt, weil sonst die Verwertung als Baustoff erschwert war. Nichteisen-Metalle – bei Rostasche aus einer Müllverbrennungsanlage (MVA) sind dies hauptsächlich Kupfer und Aluminium – können mit der Wirbelstromtechnik abgetrennt werden. Auf diese Weise sinken auch die Gehalte an umweltrelevanten Schwermetallen. Allerdings werden die kleinen Korngrößen und die chemisch gebundenen Metallen (etwa Oxide oder Carbonate) bisher in der Aufbereitung nicht erfasst. Im vorliegenden Beitrag werden die verfahrenstechnische Potenziale aufgezeigt, mit denen die Metallausbeute erhöht werden kann.
Laboratory leaching tests may be used for source term determination as a basis for risk assessment for soilgroundwater pathway (leachate forecast) on contaminated sites in Germany. Interlaboratory comparisons on the evaluation of the reproducibility of column percolation tests were conducted within the framework of an integrated R + D program using three waste reference materials.
The interlaboratory comparisons of column percolation tests showed good reproducibility of the results for inorganic and organic parameters as well as for the accompanying parameters. This is due to the stipulations concerning the time of contact between leachant and sample material as well as the sample placement in the columns. Different column dimensions used by the participants of the interlaboratory comparisons did not have any substantial influence on the column test results.
Results of German ring tests on the vaildation of leaching standards for source term determination
(2009)
Ressourcen aus Abfall
(2012)
Die Beseitigung unbehandelter Abfälle auf Deponien gehört der Vergangenheit an, nicht nur weil Verordnungen diese Praxis verbieten, sondern auch, weil wegen steigender Preise für Rohstoffe und sinkender Gehalte in Erzen auch in Abfällen nach Alternativen gesucht wird. In den Aschen aus Hausmüllverbrennungsanlagen können mit einfachen Verfahren Metalle zurückgewonnen werden. Mit dem Phosphor aus Klärschlammaschen können Düngemittel hergestellt und so natürliche Ressourcen geschont werden. In beiden Fällen ist die Anreicherung der Wertstoffe durch den Verbrennungsprozess vorteilhaft, da die Effizienz von Recyclingprozessen stark von der Konzentration im Ausgangsgut abhängig ist.--------------------------------------------------------------------------------------------------------------------------------
Disposal of untreated waste has come to end due to new legislation in this field. Furthermore as a response to increasing prices for primary raw materials and decreasing ore concentrations products from waste treatment display a source for secondary raw materials. Elemental metals can be easily separated from municipal solid waste incineration bottom ash. Fertilizers can be produced using phosphate from sewage sludge ashes thus preserving natural resources. In both cases the enrichment taking place in the incineration process facilitates the resource recovery, because the efficiency of recycling processes is dependent on the concentration of the input material.
Direct and indirect effects (DIERec) of the recovery of secondary resources are in the range of 500 million tons per year in Germany; energy savings are 1.4 million TJ. These savings are between 10 and 20% of the total. The effects of materials recovery exceed those of energy recovery by far except for secondary plastic material, where DIERec from energy recovery is higher by factor of 2.7. Untapped potential for the recovery of secondary resources exists in the fine fraction of bottom ash from municipal solid waste incineration, mainly Cu and precious metals, and in urban mining.
In Germany, the direct material input (DMI) was 1727 million tons in the year 2014. This figure would be even higher by more than 14 % if no secondary materials were already used in industrial production. For example, production of secondary Cu is advantageous due to lower energy consumption and conservation of scarce natural resources. The presentation will discuss pathways to increase the use of secondary raw materials to foster a circular economy with a focus on waste treatment processes.
Raw material supply is essential for all industrial activities. The use of secondary raw material gains more importance since ore grade in primary production is decreasing. Meanwhile urban stock contains considerable amounts of various elements. Photovoltaic (PV) generating systems are part of the urban stock and recycling technologies for PV thin film modules with CdTe as semiconductor are needed because cadmium could cause hazardous environmental impact and tellurium is a scarce element where future supply might be constrained. The paper describes a sequence of mechanical processing techniques for end-of-life PV thin film modules consisting of sandblasting and flotation. Separation of the semiconductor material from the glass surface was possible, however, enrichment and yield of valuables in the flotation step were non-satisfying. Nevertheless, recovery of valuable metals from urban stock is a viable method for the extension of the availability of limited natural resources.
Waste-to-energy (WtE) is one of the leading technologies for municipal solid waste (MSW) treatment in Europe. According to Eurostat data, in 2015, 27 % of MSW was utilized in WtE plants, which represents more than 80 million tons per year. Therefore, the European annual production of incineration bottom ash (IBA) is about 20 million tons, as it is about 25 wt% of input MSW. In the European List of Waste, IBA is listed as mirror entry (i.e. waste materials which should be classified as either non-hazardous or hazardous, depending on its hazardous properties and/or content of hazardous substances) under codes 19 01 11 and 19 01 12.
Recent trends indicate that WtE allows, apart from utilization of the energy content of waste, also the recovery of various valuable components. Hence, WtE can be included in the key technologies that can put the circular economy concept into practice. Secondary raw materials in the case of WtE are solid residues, especially IBA, as it is a secondary source, particularly of ferrous metals (Fe) and non-ferrous metals (NF) and glass. Moreover, the residual mineral fraction can be used for various applications in the construction industry, i.e. as aggregates substitute for bound or unbound applications, in cement manufacturing or, as indicated by recent research, also in more sophisticated applications, e.g. for ceramics production. Recovery of these metals can also cause huge greenhouse gas savings. Alone in Europe, metal recovery from IBA reduces greenhouse gas emissions by approximately 3.2 million tonnes of CO2 equivalent.
Resource consumption is always accompanied by environmental impacts. In most cases, it is not possible to quantify the extent of such negative impacts. However, the external cost of uranium mining in Germany can be estimated at 30 Euro/kg U. The environmental impact can be reduced when waste materials are processed, so that their use as a secondary raw material, substituting for natural resources, is possible. The recyclability of waste materials depends on the price of a resource and the concentration of the component in the waste.
The use of renewable energy technologies, such as photovoltaics (PV) should be sustainable and environmentally compatible and therefore protect the environment from risks and damaging impacts. Regarding the growing number of installed photovoltaic systems, the end-of-life management of the pv-modules will become increasingly important. Thin film panels contain hazardous substances that may harm the environment if they are not recycled or disposed properly after reaching the end of their service life. Heavy metals, for example, can be toxic as well as carcinogenic or teratogenic. Processing methods for the recycling of PV thin film modules have to take these facts into account. Currently the available recycling techniques usually utilise chemicals such as acids for a wet-chemical treatment of end-of-life modules. The aim of RESOLVED was to identify and test alternative methods for a wet-mechanical treatment in order to reduce the consumption of chemicals in the recycling of thin film modules. Furthermore, the recovered Cadmium-Telluride (CdTe) and Copper-Indium-Diselenide/Disulfide (CIS) should be helping to save scare resources especially for limited elements such as tellurium and indium. The project RESOLVED investigated the recovery of semiconductors material as secondary raw material and the decontamination of the residues of the PV thin film modules. These goals were achieved by testing and optimising existing technologies for the recycling process as well as for the enrichment of the semiconductor materials. The target is to re-use the enriched recovered material in the production of new PV modules. Special efforts were made to look into life cycle analysis, process sustainability, economical aspects, and resource availability.
The recycling of refractory materials in the chemical, metallurgical and glass industry has only had minor relevance until now because of the high performance required from these materials (stability against corrosion, inert when coming into contact with the glass melt, etc.). Refractory lifetimes are limited because of corrosion at higher temperatures. The best furnace lifetimes has been achieved with chromium oxide and chromium oxide corund refractories. Waste from the production and use of refractory material is generated in three main forms: as residues from cutting and grinding, as refractories which have limited or no contact with glass melts, and as refractories with infiltration of sublimation residues or condensates. The waste material is classified as hazardous waste due to its chromium content. In this study, arc furnace technology was used for thermal treatment of the waste materials to enable recycling of refractory materials. (author abst.)
Over the past two decades, per- and polyfluoroalkyl substances (PFASs) have emerged as worldwide environmental contaminants, calling out for sophisticated treatment, decomposition and remediation strategies. In order to mineralize PFAS pollutants, the incineration of contaminated material is a state-of-the-art process, but more cost-effective and sustainable technologies are inevitable for the future. Within this review, various methods for the reductive defluorination of PFASs were inspected. In addition to this, the role of mechanochemistry is highlighted with regard to its major potential in reductive defluorination reactions and degradation of pollutants. In order to get a comprehensive understanding of the involved reactions, their mechanistic pathways are pointed out. Comparisons between existing PFAS decomposition reactions and reductive approaches are discussed in detail, regarding their applicability in possible remediation processes. This article provides a solid overview of the most recent research methods and offers guidelines for future research directions.
In 2011, the German Association of Engineers (VDI) started working on a set of guidelines dealing with the improvement of resource efficiency. These guidelines represent a framework that defines resource efficiency and outlines proposals for the producing industry. A special guideline for small and medium-sized enterprises (SMEs) is included as well as guidelines on methodologies for evaluating resource use indicators, such as the cumulative raw material demand of products and production systems. The work on resource use indicators is still in progress. The evaluation of raw materials expenditure will include water, soil and land use. The model will include the availability of raw materials (criticality). Improving resource efficiency at the end-of-life stage is illustrated in this paper by the example of materials recovery from waste, here from residues out of municipal solid waste incineration (MSWI). With mechanical treatment valuable materials like ferrous and non-ferrous metals and secondary construction material can be extracted from MSWI bottom ash. The potential contribution on the resource efficiency is discussed.
Improving resource efficiency at the end-of-life stage is illustrated in this paper by the example of materials recovery from waste, here from residues out of municipal solid waste incineration (MSWI). With mechanical treatment valuable materials like ferrous and non-ferrous metals and secondary construction material can be extracted from MSWI bottom ash. The potential contribution on the resource efficiency will be discussed.
The production of secondary materials from waste materials requires, in most cases, significantly lower energy amounts than the primary material production of raw materials. Along with lower energy demand, the greenhouse gas emissions produced are also lower. The duty of a modern waste management system should therefore be to collect and sort the waste materials in a way that the highest amounts of single material fractions with the highest qualities can be generated. In this contribution, the greenhouse gas balances of the theoretical treatment of the household waste, if collected as mixed waste in sanitary landfills, in waste incineration plants, or in mechanical-biological treatment plants, are compared to the existing separate waste collection and treatment in Germany in 2014.
Municipal sewage sludge is a carrier of nutrients most important phosphorus (P) but also contains organic pollutants and heavy metals. A two steps thermal treatment based on 1. mono-incineration of sewage sludge under destruction of organic pollutants and 2. thermochemical treatment of the resulting ashes to remove heavy metals and increase P-bioavailability is suggested by the authors. The process aims at P-fertilisers production from sewage sludge. Seven sewage sludge ashes of different origin and composition and one residue from gasification of sewage sludge were thermochemically treated. The raw ashes were mixed with a chlorine donor (e.g. MgCl2) and thermally treated in a gas tight lab-scale rotary furnace. The distributions of the heavy metals between solid and gas phase were determined. The heavy metals concentrations of the treated ashes matched the legislative limits in most cases. The products from thermochemical treatment are suited raw materials for P-fertiliser production. Relevant process parameters such as temperature, type and concentration of Cl-donor and retention time were optimised for the thermochemical treatment step.
Bottom ash from municipal solid waste incineration (MSWI) consists of elemental metals in considerable amounts. The fine fraction < 4 mm additionally contains chemically bound metals (oxides, carbonates, silicates). Separation prospects with techniques as in ore processing (flotation, density separation, bioleaching, hydrothermal solution) are discussed. During alteration after wet extraction mineral material with hydraulic properties form coatings on almost all particles of the bottom ash and complicate separation procedures. In addition bottom ash from MSWI is a heterogeneous material. For sufficient enrichment different concerted treatment steps seemed to be essential associated with an uncertainty of economic viability. The utilisation of metal compounds present in bottom ash as secondary raw material depends on the energy- and resource-efficiency of the enrichment processes. Therefore energy and material flow considerations are presented.
Bottom ash from municipal solid waste incineration (MSWI) consists of eiemental metals in considerable amounts. The fine fraction < 4 mm additionally contains chemically bound metals (oxides, carbonates, Silicates). Separation prospects with techniques as in ore processing (flotation, density separation, bioleaching, hydrothermal solution) are discussed. During alteration after wet extraction mineral material with hydraulic properties form coatings on almost all particles of the bottom ash and complicate separation procedures. ln addition bottom ash from MSWI is a heterogeneaus material. For sufficient enrichment different concerted treatment steps seemed to be essential associated with an uncertainty of economic viability. The utilisation of metal compounds present in bottom ash as secondary raw material depends on the energy- and resource-efficiency of the enrichment processes. Therefore energy and material flow considerations are presented.
Small grain sizes of municipal solid waste incineration (MSWI) bottom ash (BA) contain elemental and chemically bonded metals in appreciable amounts, especially copper. As different copper species have in general a higher density compared to the prevalent minerals, processes for density separation seemed to be favorable for the recovery of copper. Investigations with a centrifugal classifier were therefore carried out with BA from MWSI which have been used for a few years as the covering material for a landfill. The results show an appreciable enrichment of the precious copper. The concentrates contained up to 60 mg/kg copper in the dry weight (DW) (in general about 30 – 40 mg/kg DW) with enrichment factors of around 20 and a copper recovery of up to 50 % (in general around 20 %). A test series in order to evaluate the potential benefit for sequential processing illustrate the low efficiency for a further processing of the tailings.
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.
The sequence of reactions accompanying the thermochemical treatment of an iron- and aluminium-bearing sewage sludge ash was ascertained by investigating two systematic series of samples. The ash was thermochemically treated in a lab-scale rotary furnace after mixing it with a chlorine-donor, either CaCl2 or MgCl2. Within each of these two sample series only a single process parameter, the reaction temperature, was varied, namely between 350 and 1050°C. It was found, that among the numerous crystalline phases present in the raw ash only quartz and hematite continue to exist after thermochemical treatments carried out at 1050°C, whereas all other components undergo at least one decomposition-recrystallization cycle. Some of the components re-crystallize even several times. It was proved that the restructuring of the calcium- and phosphorus-bearing mineral phases proceeds via the formation of chlorspodioside, Ca2PO4Cl. The influence of the type of chlorine-donor on the final product was elucidated in detail and - to the best of our knowledge - for the first time crystalline AlPO4 was found in a sewage sludge ash and its decomposition was investigated, too.
Geosynthetic materials are applied in measures for coastal protection. Weathering or any damage of constructions, as shown by a field study in Kaliningrad Oblast (Russia), could lead to the littering of the beach or the sea (marine littering) and the discharge of possibly harmful additives into the marine environment. The ageing behavior of a widely used geotextile made of polypropylene was studied by artificial accelerated ageing in water-filled autoclaves at temperatures of 30 to 80° C
and pressures of 10 to 50 bar. Tensile strength tests were used to evaluate the progress of ageing, concluding that temperature rather than pressure was the main factor influencing the ageing of geotextiles. Using a modified Arrhenius equation, it was possible to calculate the half-life for the loss of 50% of the strain, which corresponds to approximately 330 years.
Im Zusammenhang mit der Novellierung der Bundes-Bodenschutzverordnung und der Einführung einer Ersatzbaustoffverordnung wurden vom DIN-Normenausschuss Wasserwesen, Unterausschuss "Eluierungsverfahren" zwei Verfahren zur Elution von Feststoffen erarbeitet. Dabei handelt es sich um ein Säulenperkolationsverfahren zur gemeinsamen Untersuchung des Elutionsverhaltens von organischen und anorganischen Stoffen und ein Schüttelverfahren mit einem Wasser-/Feststoff-Verhältnis (W/F) von 2 l/kg zur Untersuchung der Elution von anorganischen Stoffen. Beide Verfahren sind für Bodenmaterialien und mineralische Abfälle mit einer Korngröße bis 32 mm vorgesehen. Der Vergleich der Praktikabilität der beiden Elutionsverfahren soll zur Diskussion zu deren Einsatz im Rahmen der geplanten bundeseinheitlichen gesetzlichen Regelungen beitragen, welche gegenwärtig kontrovers geführt wird.
Potential use of incineration bottom ash in construction – Evaluation of the environmental impact
(2020)
Knowledge of the long-term leaching behavior of potentially harmful substances is crucial for the assessment of the environmental compatibility of reusing municipal solid-waste incineration bottom ash (MSWI BA) in construction, i.e., as a road base layer.
BA fractions obtained from wet-processing aiming at the improvement of environmental quality were used to investigate the mobility of relevant substances. Eluates from laboratory-scaled leaching procedures (column percolation and lysimeters) were analyzed to learn about the long-term release of substances. Unsaturated conditions and artificial rainwater (AR) were used in the lysimeter tests to simulate field conditions. In addition, batch test eluates were generated at usual liquid-to-solid ratios (L/S) for compliance testing purposes. A variety of cations and anions was measured in the eluates.
The wet treatment reduces the leaching of chloride and particularly sulfate by more than 60%. The release of typical contaminants for the treated MSWI BA such as the heavy metals Cu and Cr was well below 1% in the conducted leaching tests.
An increase in the Sb concentration observed in the lysimeter experiments starting at L/S 0.75 L/kg and in the column experiment at L/S 4 L/kg is assumed to be related to decreasing concentrations of Ca and thus to the dissolution of sparingly soluble calcium antimonate. The same leaching mechanism applies with V, but the concentration levels observed are less critical regarding relevant limit values. However, on the long term the behavior of Sb could be problematic for the application of MSWI BA in construction.
Die Autoren zeigen dazu die gesetzlichen und energiepolitischen Rahmenbedingungen und Perspektiven auf, widmen sich in aktuellen Beiträgen zur Verfahrenstechnik der thermischen Abfallbehandlung sowohl den thermischen Hauptverfahren als auch der Abgasreinigung und gehen auf das Thema Wertstoffrückgewinnung ein. Ihr Fazit: Durch Anstrengungen, das stoffliche Recycling weiter zu optimieren, können künftig weitere Kreisläufe von Produkten und Materialien hochwertig geschlossen werden. Für manche Abfallströme wird dies aber aus verschiedenen Gründen nicht möglich sein – hier bleibt die thermische Abfallbehandlung unverzichtbar.
Die Reduzierung von Schadstoffen im Grundwasser mit reaktiven Wänden ist eine neuartiges passives Sanierungsverfahren. Die am häufigsten angewandten Dekontaminierungsprozesse sind dabei chemische Reduktion, Oxidation, Ausfällung und Sorption, die im Bericht beispielhaft dargestellt sind. Blei, Chrom und insbesondere Uran werden unter den anorganischen Schadstoffen detailliert behandelt, da solche Grundwasserverunreinigung in vielen europäischen Ländern auftreten. Baumethoden für Dichtwände und reaktive Wände weisen gemeinsame Merkmale auf. Neben den gewöhnlichen Methoden werden Bohrverfahren, deep-soil-mixing, Strahltechnologien, Brunnengalerien, Injektionssysteme und Biobarrieren angewendet, um reaktive Wände zu errichten. Die Technik der reaktiven Wände besitzt ein großes Potential für die Sanierungstechnik der Zukunft.
Permeable reactive barriers
(2005)
Contaminated land, landfills and sediments pose a serious environmental threat by polluting groundwater in the surrounding area. In 14 European countries contamination caused by uranium represents a particularly serious danger where drinking water resources might be affected. Other heavy metals and organic pollutants can also have a strongly deleterious effect on groundwater. Available technologies (e.g. pump- and-treat) fall short of solving the problem because their performance is not yet adequate for effective remediation. The aim of the project is to elaborate the scientific basis for laboratory and pilot-scale testing of and the practical application of a considerably more efficient and cost-effective in-situ reactive barrier technology targeting the above contaminants. The primary model test site will be an area in Southern Hungary contaminated by uranium mining- thus including a region which is due to become part of the European Union.
The approach taken to meet the project objectives was the characterisation of different reactive materials and relevant attenuation processes in the reactive matrix of the permeable barrier with special respect to their long-term behaviour. The experimental work included laboratory experiments at different scales, going from bench-scale tests up to pilot-scale, and field-scale experiments. Experimental conditions were predetermined by the characteristics of the model site, such as geologic and hydrogeological settings, soil composition, and type, extent and spreading of the contamination. Technological methods to enhance the long-term efficacy and cost-effectiveness of permeable reactive barrier systems were developed and tested under realistic conditions.
Per- and polyfluoroalkyl substances (PFAS) are a group of more than 4700 anionic and cationic anthrophonic substances which have been used extensively in a variety of products and industries due to their inert chemical stability and resistance to degradation by heat or acids. As a result of continuous use, mainly in aviation firefighting foams, thousands of industrial and military installations have been found to contain contaminated soil and groundwater resources. However, because of the continuous use of fluorinated consumer products, also effluents and sewage sludge from wastewater treatment plants (WWTPs) have been shown to be an important source of PFAS contamination into the aquatic environment. Resulting from recent stricter regulations and restrictions in the last years on the use of long chain (≥C8) PFAS, there is a significant shift in the chemical industry towards production of short (C4-C7) and ultrashort (C1-C3) chain alternatives. With the amendment of the Sewage Sludge Ordinance in 2017 the German legislation banned sewage sludge application on agricultural land, and by 2029/2032 sewage sludge will be completely prohibited from agricultural application. While environmental exposure of organic pollutants like PFAS, pesticides and pharmaceuticals are no longer desirable, phosphorus (P) from sewage sludge must still be used to produce high-quality P-fertilizers for a circular economy. Currently, plant-available P-fertilizers from sewage sludge/wastewater can be produced using a variety of treatment approaches including precipitation, leaching, and thermal treatment. However, the fate of legacy and emerging PFAS compounds during P leaching, precipitation and treatment from sewage sludge and wastewater is for the most parts still unknown.