Case study on enhanced landfill mining at mont-saintguibert landfill in Belgium: Characterization and potential of fine fractions

Abstract

Within the framework of the “EU Training Network for Resource Recovery through Enhanced Landfill Mining – NEW-MINE”, around 374 Mg of waste were excavated from a landfill site in Mont-Saint-Guibert, Belgium. Parameters such as bulk density, water content, particle size distribution and material composition of the fine fractions (material <90 mm) were determined and analyzed. The present investigation has the main objective to document and disseminate the findings on the material characterization of the fine fractions obtained in this case study, since such information is of critical relevance for the design of an effective and efficient mechanical processing in (enhanced) landfill mining projects. Additionally, the potential of the fine fractions for material and energy recovery is discussed. The fine fractions in question were obtained through the implementation of a ballistic separation process with simultaneous screening directly after excavation, from which about 77 wt.% of the total amount of processed material in raw state corresponded to the fine fractions. These fractions presented an overall bulk density range of 720-1000 kg/m3 in raw state and a total water content range of 25-30 wt.%. In dry state, the material showed a more uniform particle size distribution than in raw state, and results confirm that water content has a large impact on the particle size distribution of the fine fractions, as well as on the content of impurities in the material fractions “Combustibles”, “Inert”, “Total metals” and “Others” and on the presence of agglomerates. Results on the material composition in dry state reveal that amounts of 2.1-19.7 wt.% “Combustibles”, 31.1-35.4 wt.% “Inert” and 0.6-1.8 wt.% “Total metals” could be recovered from the fine fractions 90-10 mm, while 37.8-55.6 wt.% “Fine fractions <10 mm” could be processed further in order to increase the recovery amounts of the previous material fractions and produce a substitute material for soil in construction applications.