Abstract
The disposal of Municipal Solid Waste (MSW) in sanitary landfills produces leachate, whose composition changes depending on the microbial community and the environmental conditions. However, these changes cannot be observed in sanitary landfill because of the superposition of cells, which makes it difficult to determinate the relationship among the phases of biodegradation of MSW, the composition of the leachate and the time required for complete stabilization of the waste. This illustrates the importance of building experimental cells that simulate landfill to monitor the leachate over a long period. This study aimed to analyze the composition of the leachate generated from an experimental cell built on the Delta A sanitary landfill of Campinas City, Brazil, over 945 days. The leachate showed a transition from an acidic anaerobic phase to a methanogenic phase within approximately 100 days. By the one-hundredth day, the leachate showed a characteristically low pH, between 5.0 and 6.0 and a high Chemical Oxygen Demand (COD) and Biochemical Oxygen Demand (BOD) such as a young leachate with high biodegradability. Moreover, there was an intense leaching of the metals Cd, Fe, Pb and Mn, with concentrations higher than those allowed for the release in water bodies, according to Brazilian law. After the one-hundredth day, the leachate was characterized as stabilized. The pH increased and the concentration of volatile fatty acid, COD and BOD decreased. Co, Zn, Ni and Cu were leached. The potentially toxic metal concentrations found in the leachate also were above the values allowed by Brazilian law.
Highlights
Brazil produces 259,547 t of Municipal Solid Waste (MSW) daily, with 167,636 t day−1 of these wastes disposed in sanitary landfills (IBGE, 2010)
One of the disadvantages of this disposal technique is the production of leachate and biogas; depending on leachate composition, which is related to the state of biodegradation of the MSW disposed in the landfill, leachate treatment is fairly complex and costly (Kjeldsen et al, 2002)
Physicochemical analysis of the leachate generated from MSW confined in an isolated experimental cell built on the Delta A sanitary landfill in Campinas, southeastern Brazil, enabled to observe the early transition-approximately 100 days - from the acid anaerobic phase to the methanogenic phase of biodegradation of the MSW
Summary
Brazil produces 259,547 t of Municipal Solid Waste (MSW) daily, with 167,636 t day−1 of these wastes disposed in sanitary landfills (IBGE, 2010). The variations in the leachate composition due to biodegradation of the MSW cannot be observed in sanitary landfill due to the superposition of cells that allows the mix of the leachate generated from wastes of different ages. This fact makes it difficult to establish the relationship among the phases of biodegradation of the MSW, the composition of the leachate and the time required for the complete stabilization of waste, i.e., methanogenic conditions (Kjeldsen et al, 2002)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
