TY - JOUR A1 - Lopez Meza, Sarynna A1 - Kalbe, Ute A1 - Berger, Wolfgang A1 - Simon, Franz-Georg T1 - Effect of contact time on the release of contaminants from granular waste materials during column leaching experiments N2 - When reusing or disposing of contaminated granular waste materials there is a need to evaluate how the contaminants will interact on the pathway soil-groundwater and the effect this interaction will have on the surrounding environment. While column testing can provide a closer approximation to field percolation conditions than batch testing, there is still a need to develop column testing procedures that consider the requirements of practical testing time frames. This study evaluates the effect of different column contact times (2.5, 5, and 16 h) on the release of inorganic constituents from bottom ash and demolition waste, two commonly reused granular materials. Leaching data for representative constituents of concern, such as copper, chromium, sulfate and chloride, as well as pH and electrical conductivity was compared for all different contact times studied. Results for the materials investigated in this study showed that variations in contact time have no significant effect on the release of the selected constituents and leaching parameters at low liquid to solid ratios. However, after a liquid to solid ratio of 1 L/kg, the effect is more noticeable, and higher contact times show lower pH values as well as a reduction in the release of constituents of concern from bottom ash. In the case of demolition waste, the variation of contact time did not have a strong effect on the leaching behavior. KW - Leaching procedures KW - Standardisation KW - Column tests KW - Contact time KW - Granular materials KW - Waste PY - 2010 U6 - https://doi.org/10.1016/j.wasman.2009.11.022 SN - 0956-053X VL - 30 IS - 4 SP - 565 EP - 571 PB - Pergamon Press CY - New York, NY AN - OPUS4-20934 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Berger, Wolfgang A1 - Simon, Franz-Georg A1 - Weimann, Karin A1 - Alsema, E. A. T1 - A novel approach for the recycling of thin film photovoltaic modules N2 - A sustainable recycling of photovoltaic (PV) thin film modules gains in importance due to the considerable growing of the PV market and the increasing scarcity of the resources for semiconductor materials. The paper presents the development of two strategies for thin film PV recycling based on (wet) mechanical processing for broken modules, and combined thermal and mechanical methods for end-of-life modules. The feasibility of the processing steps was demonstrated in laboratory scale as well as in semi-technical scale using the example of CdTe and CIS modules. Pre-concentrated valuables In and Te from wet mechanical processing can be purified to the appropriate grade for the production of new modules. An advantage of the wet mechanical processing in comparison to the conventional procedure might be the usage of no or a small amount of chemicals during the several steps. Some measures are necessary in order to increase the efficiency of the wet mechanical processing regarding the improvement of the valuable yield and the related enrichment of the semiconductor material. The investigation of the environmental impacts of both recycling strategies indicates that the strategy, which includes wet mechanical separation, has clear advantages in comparison to the thermal treatment or disposal on landfills. KW - Recycling KW - Photovoltaic KW - Thin film modules KW - CdTe KW - CIS KW - Mechanical processing KW - Life cycle analysis PY - 2010 U6 - https://doi.org/10.1016/j.resconrec.2009.12.001 SN - 0921-3449 VL - 54 IS - 10 SP - 711 EP - 718 PB - Elsevier CY - Amsterdam [u.a.] AN - OPUS4-21439 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -