| Abstract
| - We investigated the release of chloride, sulfate, sodium, copper, chromium, and dissolved organic carbon from a demolition waste material and a municipal waste incineration product. Batch leaching tests at the liquid-to-solid ratios (L/S ratios) 1, 2, 5, 10, and 50 L kg−1 were carried out and the parameters of a mass balance-partitioning model were estimated from measured concentrations in the extracts by applying a Bayesian approach using a Markov Chain Monte Carlo sampler. We assessed the uncertainty of the model parameters, the desorption isotherms, and the model-predicted concentrations, respectively. Both the excellent fit to the experimental data and a comparison between the model-predicted and independently measured concentrations at the L/S ratios of 0.25 and 0.5 L kg−1 showed the applicability of the model for almost all studied substances and both materials. Since experimental difficulties impede extraction tests at L/S ratios representative of field soil-water contents, the predictability of concentrations in this range is of great practical relevance for risk assessments. We conclude that batch extraction tests at varying L/S ratios provide, at moderate experimental cost, a powerful complement to established test designs like column leaching or single batch extraction tests.
- Contaminant release from waste materials is studied using batch extraction tests to predict concentrations at liquid-to-solid ratios representative for in-situ conditions.
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