TRATAMENTO ANAERÓBIO E AERÓBIO DE LIXIVIADO DE ATERRO SANITÁRIO

Abstract

Landfill leachate can be considered a liquid waste holder of high concentration of ammonia nitrogen, recalcitrant organic matter and, according to the chemical composition of solid waste landfill and the age of the earth, significant concentrations of heavy metals. Such characteristics require sophisticated alternative technologies for the treatment of leachate due to its imbalance between the nutrient and the possible generation of potential toxic products in case of biological process, or other byproducts in case of physical and chemical processes. Conjugated treatment of landfill leachate and sewage is emerging as a promising technological alternative, however, it also recognizes the necessity of operating parameter settings, especially regarding the application of this type of treatment in real scale. In this context, this study worked with the conjugated treatment of landfill leachate and domestic sewage in UASB reactor, followed by biological trickling filter, applying volumetric organic loads of 1.0 kgBOD5 / m3.dia (step 1), 1.2 kgBOD5 / m3.dia (step 2) and 1.5 kgBOD5 / m3.dia (step 3) and HRT of 7.5, 5.0 and 18.0 hours, respectively. The efficiency of total COD removal in the two reactors were 85%, 57% and 89% for steps 1, 2 and 3, respectively. It also presented satisfactory removal of N-NH4 +, producing, in step 2, an effluent with average concentration of 17 mg N-NH4 +.L-1. This result meets the discharge standards into water bodies, once that the maximum value allowed is 20 mg N-NH4 +.L-1.

Key words: wastewater; combined treatment; UASB reactor; percolator biological filter.