Tratamento biológico conjugado de lixiviado de aterro sanitário e esgoto doméstico

Abstract

Landfill leachate is a liquid waste with high concentrations of organic and inorganic matter, ammonia nitrogen, among other contaminants that can cause adverse effects on the environment. In view of its chemical characteristics, leachate needs adequate treatment before being released into receiving bodies. One of the alternatives employed is the combined treatment of landfill leachate and domestic sewage. Therefore, the objective of the present work was to evaluate the applicability of the combined treatment of landfill leachate and domestic sewage in a system consisting of UASB reactor, percolator biological filter (PBF) and anoxic reactor (AR). The substrate used to feed the UASB reactor consisted of a mixture of 97% of domestic sewage with 3% of landfill leachate (percentage by volume). The operation of the experimental system was divided into two phases to evaluate the effect of adding oxygen to the nitrification process, the first lasting six months and the second lasting two months. The average removal efficiencies, for the treatment system, of the total chemical oxygen demand (CODtotal), filtered chemical oxygen demand (CODfiltered) and ammoniacal nitrogen (N-NH4^+) were 82, 63 and 16% and 80, 66 and 50%, in phases 1 and 2, respectively.It was found that forced aeration in the percolator biological filter during phase 2 enabled greater efficiency in the nitrification process, providing removal of 50% of ammoniacal nitrogen.