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- Lysimeter (2)
- Antimony (1)
- Bottom ash (1)
- Cadmium (1)
- Column percolation tests (1)
- Elutionsverhalten (1)
- Ersatzbaustoff (1)
- Fertilizer (1)
- HMVA (1)
- Hausmüllverbrennungsasche (1)
Organisationseinheit der BAM
Im Rahmen eines ZIM-geförderten Projektes wurde eine nass-mechanische Aufbereitung von Hausmüllverbrennungsasche (HMVA) hinsichtlich der Mengen und der Qualitäten generierter Fraktionen optimiert. Dabei standen besonders die Qualitäten der mineralischen Fraktionen, die mengenmäßig den größten Anteil darstellen, im Vordergrund, da sie für einen möglichen Einsatz als Baustoff nutzbar gemacht werden sollen. Insbesondere die Chlorid- und Sulfatgehalte sollten dafür reduziert werden. Durch die BAM wurde im Projekt u. a. die Freisetzung von umweltrelevanten Stoffen in den mineralischen Fraktionen untersucht. Dafür wurden Schütteleluate als Übereinstimmungstest und Eluate aus Lysimeterversuchen im Labormaßstab zur Bewertung des Langzeitverhaltens auf ihre Inhaltsstoffe analysiert.
In Deutschland fallen aktuell über 5 Mio. Tonnen Hausmüllverbrennungsaschen (HMVA) pro Jahr an. Aus diesen werden nur ca. 8 % Metalle (davon ca. 1 % NE-Metalle) zurückgewonnen. Zur Beurteilung des Wertstoffpotentials werden die HMVA nach standardisierten Vorschriften beprobt, für die Analytik vorbehandelt/vorbereitet/aufgearbeitet und auf ihre Inhaltsstoffe analysiert. Im nachfolgenden Beitrag wird der Schwerpunkt auf die Probenvorbehandlung und -vorbereitung gelegt, wobei der Merkmalstransfer von der Ausgangs-(Feld-)Probe über die Laborprobe und die Prüfprobe bis zur Mess-(Analysen-) Probe am Beispiel von NE-Metallen einer nassaufbereiteten HMVA untersucht wurde. Die Ergebnisse wurden mit Hilfe statistischer Methoden bewertet. Die Ergebnisse zeigen, dass die Verteilung der NE-Metalle in den einzelnen Schritten der Probenbehandlung elementspezifisch ist. Bei Blei ist ein Erhalt der Merkmalsverteilung über alle Behandlungsschritte erkennbar. Bei Kupfer nehmen die Konzentrationen in den aufeinander folgenden Behandlungsschritten deutlich ab. Die Ursache könnte das in der Feinfraktion enthaltene metallische Kupfer mit seinen spezifischen Eigenschaften sein. -------------------------------------------------------------------------------------------------------------------------------------------
More than 5 billion tons of municipal solid waste incineration bottom ashes (MSWI BA) are generated by incineration per year in Germany. Currently only 8 % of metals (of these 1 % are non-ferrous metals) are recovered from MSWI BA. For characterization of recovery potential, MSWI BA samples have to be taken, pre-treated and analyzed according to standardized methods. This manuscript focuses on sample pre-treatment and preparation of a MSWI BA sample aiming to investigate the characteristics transfer over the process of sub-sampling from the original (field) sample to the laboratory sample, test sample until the analytical sample. All results have been evaluated with statistical methods. The results show that influence of each single pre-treatment and preparation step on metal content differs for the individual metals. For lead a conservation of characteristics distribution can be observed, while for copper a continuous decline of solid concentration is observed over all preparation steps. One possible reason may be the fact that copper is mainly contained in the fine fraction as metallic copper with specific properties.
An Annex XV restriction dossier for cadmium in artists’ paints was submitted by an EU member state to the European Chemicals Agency ECHA. By cleaning used brushes under the tap cadmium can enter the food chain via waste water treatment and subsequent agricultural application of the sewage sludge. It was estimated that 110 kg Cd per year is spread on agricultural land via this exposure route. Other sources of Cd amount to almost 120 tons per year.
The mobility of Cd from pigments was studied in a field-like scenario by leaching experiments using soil samples amended with sewage sludge and spiked with Cd pigments in percolation columns. The redox conditions were confirmed to be the decisive factor for the release of Cd. The release of Cd from artists’ paints was in most cases 1% or lower in the experiments performed.
Cd from artists’ paints in sewage sludge applied in agriculture will be mobilized for intake by crops or to leaching either by oxidation of sulfide to sulfate or by dissolution at lower pH values. The quantity of Cd from artists’ paints calculated in the restriction dossier is however negligible compared to other sources of Cd to agricultural soil. Therefore ECHA did not consider the proposed restriction to be the most appropriate EU wide measure to address the negligible level of risk. In the presentation sources of Cd on agricultural land will be discussed together with possible policy instruments to mitigate such emissions.
Background: An Annex XV restriction dossier for cadmium in artists’ paints was submitted by an EU member state to the European Chemicals Agency ECHA. By cleaning used brushes under the tap cadmium can enter the food chain via waste water treatment and subsequent agricultural application of the sewage sludge. It was estimated that 110 kg Cd per year is spread on agricultural land via this exposure route. Other sources of Cd amount to almost 120 tons per year.
Results: The mobility of Cd from pigments was studied in a field-like scenario by leaching experiments using soil samples amended with sewage sludge and spiked with Cd pigments in percolation columns. The redox conditions were confirmed to be the decisive factor for the release of Cd. The release of Cd from artists’ paints was in most cases 1% or lower in the experiments performed.
Conclusions: Application of sewage sludge containing Cd from artist paints does not increase the amount of Cd leached from this soils. Furthermore the quantity of Cd from artists’ paints calculated in the restriction dossier is negligible compared to other sources of Cd to agricultural soil. Therefore ECHA did not consider the proposed restriction to be the most appropriate EU wide measure to address the negligible level of risk.
The industrial sector of bottom ash (BA) treatment from municipal solid waste incineration (MSWI) in Germany is currently changing. In order to increase the recovery rates of metals or to achieve a higher quality of mineral aggregates derived from BA, new procedures have been either implemented to existing plants or completely new treatment plants have been built recently. Three treatment trains, which are designated as entire sequences of selected processing techniques of BA, are introduced and compared. One treatment train is mainly characterized by usage of a high speed rotation accelerator whereas another is operating completely without crushing. In the third treatment train the BA is processed wet directly after incineration. The consequences for recovered metal fractions and the constitution of remaining mineral aggregates are discussed in the context of legislative and economical frameworks. Today the recycling or disposal options of mineral residues still have a high influence on the configuration and the operation mode of the treatment trains of BA despite of the high value of recovered metals.
Recycled plastic granules of high-density polyethylene, polyvinyl chloride and polystyrene the size of microplastics were exposed to artificial aging conditions (2000 h; photooxidative and thermo-oxidative) to simulate their fate outdoors. Their potential to leach into water during the aging process was investigated using column percolation tests.
Aging-related changes on the surface of the material were characterised by IR measurements indicating oxidation reactions with the formation of new adsorption bands (C=O, C–O and OH), especially in the case of photooxidative aging.
These findings were confirmed by the identification of leachable organic compounds. Leaching of total organic carbon, Cl, Ca, Cu and Zn is clearly affected by changes due to aging, and their release is increased after photooxidative aging.
In general, exposure to photooxidative conditions shows a greater influence on aging and thus on leaching and seems to be the more important mechanism for the aging of microplastic in the environment. Comparison with the total content of inorganic species revealed that, for most elements, less than 3% of the total content is released after 2000 h of photooxidative aging.