This study compares the leachates generated in the treatment of Municipal Solid Wastes (MSW) of similar origin but managed in two different ways: (a) sorting and composting in a Treatment Plant in Aranda de Duero (Burgos, Spain), and (b) direct dumping in a landfill in Aranda de Duero (Burgos, Spain) with no prior treatment. Two different leachates were considered for the former: those generated in the fermentation shed (P1) and those generated in the composting tunnels (P2); another leachate was collected from the landfill (P3). Physical and chemical properties, including heavy metal contents, were seasonally monitored in the different leachates. This study allowed us to conclude that the sampling season had a significant effect on Pb, Cd, Ni, Mg and total-N contents (P < 0.01). Similarly, leachates P1, P2 and P3 exhibited significant overall differences for most of the measured parameters except for Cd, Cu, Pb, K, Fe, C-inorg and C-org contents (P < 0.01). This study concludes with the feasibility of a whole treatment for both leachates using ultrafiltration in a membrane bioreactor (MBR).
Keywords: Leachate; MBR; composting plant; heavy metals; landfill; ultrafiltration.