Suchergebnisse

Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG geförderten) Allianz- bzw. Nationallizenz frei zugänglich. ; This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively. ; Waste electrical and electronic equipment (WEEE) contains gold in low but from an environmental and economic point of view relevant concentration. After collection, WEEE is pre-processed in order to generate appropriate material fractions that are sent to the subsequent end-processing stages (recovery, reuse or disposal). The goal of this research is to quantify the overall recovery rates of pre-processing technologies used in Germany for the reference year 2007. To achieve this goal, facilities operating in Germany were listed and classified according to the technology they apply. Information on their processing capacity was gathered by evaluating statistical databases. Based on a literature review of experimental results for gold recovery rates of different pre-processing technologies, the German overall recovery rate of gold at the pre-processing level was quantified depending on the characteristics of the treated WEEE. The results reveal that — depending on the equipment groups — pre-processing recovery rates of gold of 29 to 61% are achieved in Germany. Some practical recommendations to reduce the losses during pre-processing could be formulated. Defining mass-based recovery targets in the legislation does not set incentives to recover trace elements. Instead, the priorities for recycling could be defined based on other parameters like the environmental impacts of the materials. The implementation of measures to reduce the gold losses would also improve the recovery of several other non-ferrous metals like tin, nickel, and palladium.

In theory, individual producer responsibility (IPR) creates incentives for "design-for-recycling". Yet in practice, implementing IPR is challenging, particularly if applied to waste electric and electronic equipment. This article discusses different options for implementing IPR schemes and producers' under German WEEE legislation. In addition, practical aspects of a German "return share" brand sampling scheme are examined. Concerning "new" WEEE put on the market after 13 August 2006, producers in Germany can choose between two different methods of calculating take-back obligations. These can be determined on the basis of "return shares" or "market shares". While market shares are regularly monitored by a national clearing house, the "return share" option requires sampling and sorting of WEEE. Herein itis shown that the specifics of the German WEEE take-back scheme require high sample sizes and multi-step test procedures to ensure a statistically sound sampling approach. Since the market share allocation continues to apply for historic waste, producers lack incentives for choosing the costly brand sampling option. However, even return share allocation might not imply a decisive step towards IPR, as it merely represents an alternative calculation of market shares. Yet the fundamental characteristics of the German take-back system remain unchanged: the same anonymous mix of WEEE goes to the same treatment operations. In the future, radio frequency identification-based sorting options could foster IPR and incentives for changes in product design. ; Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich. - This publication is with permission of the rights owner freely accessible due to an Alliance licence and a national licence (funded by the DFG, German Research Foundation) respectively.

In Notebooks und vielen anderen mobilen Geräten der Informations- und Kommunikationstechnik (IKT) hat der Akku oft eine kürzere Lebensdauer als das Gesamtprodukt. Bei einem mobilen Gerät, bei dem der Akku nicht ausgewechselt werden kann, begrenzt die Lebensdauer des Akkus auch die Lebensdauer des Gesamtproduktes. Trotzdem ist über die tatsächliche Lebensdauer von Lithium-Akkumulatoren (Lithium-Akkus), deren Lebenszyklus und den damit verbundenen Umweltwirkungen nur relativ wenig bekannt. Das Forschungsvorhaben untersucht die Lebensdauer von Lithium-Akkus im Labor und im Feld. Im Ergebnis zeigt sich, dass aktuelle Lithium-Akkus für Tablet-PC unter Laborbedingungen mehrere hundert oder tausend Ladezyklen durchlaufen können, bis das Ende der nutzbaren Lebensdauer erreicht wird. Die Daten der Notebook-Akkus im Feld streuen stark, deuten jedoch auf nur wenige hundert Ladezyklen. Unterschiede zwischen verschiedenen Herstellern und verschiedenen Nutzungsszenarien sind deutlich erkennbar. Die Umweltwirkungen eines Lithium-Kobaltoxid (LCO)-Notebook-Akkus wurden mithilfe von Primärdaten eines großen Akkuherstellers sowie Sekundärdaten für das End-of-Life (EOL) abgeschätzt. In den untersuchten Umweltwirkungen über den gesamten Lebenszyklus des Lithium-Akkus eines Notebooks dominiert die Herstellungsphase eindeutig, wobei die Nutzungsphase dem Endgerät zugerechnet und damit nicht betrachtet wird.