Recovery and Utilisation of Municipal Solid Waste Incineration Bottom Ash: Implications for European Waste Management Strategy

Abstract

Over the last two decades, the stated intent of European waste management strategy has evolved from a specific focus on landfill diversion to enabling the transition to a circular economy.. Widespread introduction of source-segregation alongside deployment of material recovery technologies have improved MSW management practices across Europe. However, with diminishing returns it has become more difficult to achieve further landfill diversion through increased recycling alone, and incineration rates (across the EU-27 as a whole) have continued to increase. The advantages of incineration include the ability to harness the energy content of the waste alongside a sizeable reduction in mass and volume. However, the remaining solid residues, the most substantial being incinerator bottom ash, present a management issue. Exploring the role of incineration and the utilisation of incineration bottom ash, this paper highlights the potential risks of lock-in in the context of evolving waste policy. A simple thought experiment suggests that while increased use of incineration may help member states achieve 2035 landfill diversion targets, it would also carry a substantive risk of placing the 2035 recycling target out of reach. To address this, a long-term vision concerning the future of incineration is required, where it is recommended that policy which focuses on landfill diversion and the recycling of residual wastes should be strengthened through mechanisms that gradually phase out incineration and distinguish between open and closed-loop recycling.