Solubility of elements in waste incineration fly ash and bottom ash under various leaching conditions studied by a sequential extraction procedure.

An optimized 7-step sequential extraction was applied to fly ash samples from two waste incineration plants and a bottom ash sample. The solubility of 37 elements in water under alkaline and neutral conditions, ion exchange, acid solubility as well as the influence of reducing and oxidizing agents, were investigated using reagents which are typically applied in sequential extractions. Potential error sources and the suitability and selectivity of individual steps and extracting agents were also evaluated.

Quantification of main and trace metal components in the fly ash of waste-to-energy plants located in Germany and Switzerland: An overview and comparison of concentration fluctuations within and between several plants with particular focus on valuable metals.

The elemental composition of fly ash from six waste-to-energy (WTE) plants in Germany and two WTE plants in Switzerland were analyzed. Samples were taken daily over a period of one month and mixed to a composite sample for each German plant. From two Swiss plants, two and three of these composite samples, respectively, were collected for different months in order to assess temporal differences between these months.