Managing Cd Containing Waste—Caught by the Past, the Circular Economy Needs New Answers

Abstract

What is understood by the circular economy concept is the re-use and recycling of used materials and waste. In many used products, hazardous compounds are found or might be present either because of the products' present intended use or former applications that have been banned in the meantime. Clearly, recycling activities should not endanger man and environment through carryover of contaminants. To learn more about how hazardous chemicals in waste impede the circular economy, it is necessary to investigate the ways in which products containing hazardous compounds have been handled up to now in order to avoid secondary contamination. For this study, cadmium (Cd) in NiCd batteries and accumulators and Cd compounds used as stabilisers for PVC profiles were selected as examples. The situation in the European Union was analysed, with a focus on legislation, collection, recycling, disposal and the further fate of "co-recycled" Cd. Insufficient collection rates, partially unsafe disposal and carryover were identified as the main problems. An advanced management strategy for Cd and its compounds is needed in order to mitigate problems in the circular economy. Used products containing hazardous substances ought to be recycled without contaminating the environment or recycled materials. The results suggest that circular economy is faced with different, partially insurmountable challenges.

How should we deal with the interfaces between chemicals, product and waste legislation?

“…This applies, for example, to the recycling of PVC with Cd values of up to 0.1% by weight and thus ten times above the usual limit value: As long as the stabiliser is firmly bound into the PVC, there is no risk of exposure during the use phase. Only if the material is used as a secondary raw material in other PVC products or waste from these products is not treated properly does it pose a risk of human exposure and environmental contamination [36]. The examples in Table 3 illustrate that-if decontamination is not possible-separate collection and further processing results in products to which, due to their use or the respective matrix, humans and the environment are not exposed.…”

Characterizing the Urban Mine—Simulation-Based Optimization of Sampling Approaches for Built-in Batteries in WEEE

“…However, the collection rate of portable batteries throughout European Union (EU) member states is low and stagnating between 25 and 45% [3] caused by, among others, hibernation in the 'urban mine' [2] and disposal via complementary waste streams such as residual waste [4][5][6][7][8][9][10][11][12][13]. Furthermore, batteries still contained in WEEE might not be separated prior to or during WEEE treatment [13][14][15][16][17][18][19][20] and will accordingly not be sent to an adequate battery treatment. In particular, built-in batteries can only be separated with great effort.…”