Microbial biodegradation of landfill leachates located in São Paulo state, Brazil

Background Leachate is one of the most problems present in landfills, mainly due to large production and the ability to cause serious environmental damages next to these areas. An activated sludge process is commonly used for biodegrading organic contaminants in wastewater using a mixed population of microorganisms. This technology is consolidated for wastewater treatment, and recently has been used as the first step in leachate treatment process. In this work, initially, physical-chemical and biological parameters of the leachate from different landfills (Areais and Bandeirantes, both in SP), were evaluated. Also the microbial consortium present in the sludge from a wastewater plant of the Capuava Petrobras Refinery, (SP) was characterized. Purpose of this work was to study the kinetic properties of the activated sludge process by removal of the pollutant organic matter, represented by the decrease of Total Organic Carbon (TOC). In order to verify the bioremediation efficiency, experiments were developed comparing the leachates before and after biological treatments. Results show that combination of leachate and sludge can decrease the organic load significantly, demonstrating bioremediation efficiency.