Resource recovery potentials by landfill mining and reclamation in South Korea

In the existing paradigm for waste management, landfills are the final disposal site for waste with no control over the waste being sent to the sites. However, the expanding number of landfills that are at the end of their lifespans and the increasing amount of waste disposed of to landfills have presented a growing need for a shift in this paradigm, which can be achieved by the active promotion of landfill mining and resource recovery. In this study, we analyze the landfill resource recovery potentials to understand the effects on landfill lifespan extension, reduction in landfill disposal rate, energy saving, and reduction in greenhouse gas (GHG) emissions. Simulations based on material flow analysis were conducted on existing landfills, which were categorized into four different types based on their remaining capacities and availability of nearby incineration or SRF facilities. The resource recovery potentials, GHG reduction effect, and energy saving effect were higher for Type 2-1 and Type 2-2 landfills with higher ratios of combustible waste. The landfill lifespan extension effect was the highest for Type 2-2 landfill which receives a relatively smaller amount of waste than the other landfills. The reduction in landfill disposal rate was highest for Type 3, which does not have an incinerator or SRF facilities nearby. On the other hand, the overall effects, including the effect on reducing the landfill disposal rate, are the lowest for Type 1 because the chosen landfill only covers a significantly small proportion of the total waste generated in the city compared to the other landfills. The findings of this study suggest that appropriate landfill mining and reclamation operations are integral to prolonging the lifespans of existing landfills and present insights for building future landfill management strategies.