Paradigm shifts in incinerator ash, sediment material recovery and landfill monitoring

The current paper discusses some selected developments for efficient management of the globally increasing quantity of waste. Incinerator bottom ash (IBA), the heavier ash generated during incineration of municipal waste, is currently utilised in two distinct ways. One pathway is not to fragment IBA and use it as a building material in road construction. This results in reduced landfilled residual but low metal recovery. The other way is to crush the mineral aggregate, thus maximising metal recovery but resulting in higher landfilled, end material. Here emphasis is placed on the second approach as implemented in Switzerland together with the economics and need for improvement of metal recovery from IBA and fly ash. The second theme reports on the viability of recycling mussel shells as a partial substitute for cement to stabilise dredged marine sediments mechanically. This can reduce the consumption of natural resources and lower the amount of binders used in sediment stabilisation practices. Finally, the adequacy of EU's requirements regarding monitoring of groundwater pollution from landfills is assessed, and recommendations are provided to use bioindicators to determine the impact of landfills on surrounding vegetation.