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 T2 - Waste management 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. PB - Pergamon Press CY - New York, NY KW - Leaching procedures KW - Standardisation KW - Column tests KW - Contact time KW - Granular materials KW - Waste PY - 2010 UR - https://opus4.kobv.de/opus4-bam/frontdoor/index/index/docId/20934 AN - OPUS4-20934 SN - 0956-053X VL - 30 IS - 4 SP - 565 EP - 571 AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany