BIOLOGICAL TREATMENT CONJUGATED OF LANDFILL LEACHATE AND WASTEWATER

Abstract

Landfill leachate is a liquid waste with high concentrations of organic and inorganic matter, recalcitrant compounds, ammoniacal nitrogen, among other contaminants that can cause adverse effects on the environment. In view of its chemical characteristics, the leachate needs treatment before being launched into receiving bodies. Therefore, the objective of the present work was to evaluate the performance of a biological treatment system for landfill leachate plus domestic sewage, on a pilot scale, consisting of a UASB reactor, a percolator biological filter (PBF) and an anoxic reactor (AR). The substrate used to feed the UASB reactor consisted of a mixture of domestic sewage (97%) plus landfill leachate (3%). The mean efficiencies for the removal of total and filtered chemical oxygen demand, total suspended solids were, respectively, 82, 64 and 88%. Low efficiency of removal of ammoniacal nitrogen was observed in the FBP, providing a reduction of 16%. In the anoxic reactor, the denitrification process was observed, producing effluent with an average concentration of 0.42 mg.L-1.