Pre-processing is a crucial step to ensure the efficiency of subsequent processes and the quality of recyclates. The efficiency of pre-processing can be affected by high losses to undesignated output fractions. Standard batch tests usually provide mass balances and are a good proxy for bulk materials balances (iron/steel, aluminum, plastics). This article aims at harmonizing methodologies and recommends a strategy for further study in pre-processing on a plant scale. We have developed an “extended batch test” method, which should help to • describe the fates of materials and elements, • assess the quality of output fractions, • identify access points for critical metals and other valuable elements to enable their recovery. A methodical approach was compiled with common material flow analysis methods and an extended set of methods, which improve the reliability via the assessment of uncertainties. This applies to systematic effects and random effects. This extended batch test was performed with a 40 Mg Waste Electrical & Electronic Equipment (WEEE) batch to trace the flows of industrial base metals, precious metals and critical metals in a WEEE pre-processing plant. Results show that one-third of the input was separated and sorted manually, while the remaining material was subsequently crushed and automatically sorted. Copper and precious metals are distributed to various output fractions but are most concentrated in the sorting residues. Critical metals like cobalt and rare earth elements are mainly concentrated in the manually sorted materials but also appear in the ferrous metals scrap and the shredder light fraction
<p>For assessing the health risk at recreational waters resulting from wastewater discharges from urban catchments, knowledge about the dynamics of the ratio between faecal indicator bacteria and pathogenic viruses is essential. Differences in wastewater concentrations, decay rates, and relevant exposure concentrations may influence how reliable concentrations of faecal indicator bacteria truly reflect existing health risk. Full-scale experiments on decay rates of pathogenic viruses in natural surface waters, especially fresh waters, are largely missing.</p> <p>In the present study, we quantified the decay rates of faecal indicator bacteria and pathogenic viruses in a natural surface water. To this end, we performed two Lagrangian sampling campaigns after combined sewer overflows (CSO) along a river section in Berlin, Germany. During the campaigns the same body of contaminated water was resampled while travelling through the city. Organic micro-pollutants (Gabapentine, Acesulfame), and inorganic ions (Cl<sup>-</sup>, SO<sub>4</sub><sup>2-</sup>) were analysed to function as conservative tracer substances. Wastewater and stormwater amounts were estimated in each sample. Furthermore, all samples were analysed for humane Norovirus GII, Adenovirus 40/41, somatic coliphages, f-specifc coliphages, intestinale enterococci, and <em>E.coli.</em> Decay rates were derived by relating the pathogens to the estimated fraction of wastewater. The observation time was 5 and 2 days for the first and second CSO event, depending on the flow of the river. Decay rates indicate a significant variability between organisms but also between sampling campaigns as a result of different physical-chemical conditions. While the oxygen was completely consumed in the wastewater plume of the first event, this was not the case during the second event, which still allowed pathogen removal by grazing of heterotrophic zooplankton. Our results contribute to the general understanding of pathogens and faecal indicators in surface waters.</p>
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.