To fractionate municipal solid waste incineration bottom ash: Key for utilisation?
Research output: Contribution to journal › Article › Scientific › peer-review
For the past decade, the Finnish waste sector has increasingly moved from the landfilling of municipal solid waste towards waste
incineration. New challenges are faced with the growing amounts of municipal solid waste incineration bottom ash, which are mainly
landfilled at the moment. Since this is not a sustainable or a profitable solution, finding different utilisation applications for the
municipal solid waste incineration bottom ash is crucial. This study reports a comprehensive analysis of bottom ash properties from
one waste incineration plant in Finland, which was first treated with a Dutch bottom ash recovery technique called advanced dry
recovery. This novel process separates non-ferrous and ferrous metals from bottom ash, generating mineral fractions of different
grain sizes (0–2 mm, 2–5 mm, 5–12 mm and 12–50 mm). The main aim of the study was to assess, whether the advanced bottom
ash treatment technique, producing mineral fractions of different grain sizes and therefore properties, facilitates the utilisation of
municipal solid waste incineration bottom ash in Finland. The results were encouraging; the bottom ash mineral fractions have
favourable behaviour against the frost action, which is especially useful in the Finnish conditions. In addition, the leaching of most
hazardous substances did not restrict the utilisation of bottom ash, especially for the larger fractions (>5 mm). Overall, this study has
shown that the advanced bottom ash recovering technique can be one solution to increase the utilisation of bottom ash and furthermore
decrease its landfilling in Finland.