Remoção de nutrientes do efluente de um Dafa, tratando esgoto doméstico, através de um sistema Bardenpho.

Abstract

The present work aimed to analyze the feasibility of using an activated sludge system for the biological removal of nutrients from the effluent of a digester anaerobic treating domestic sewage. An experimental investigation was carried out using a hybrid sewage treatment system, consisting of a pre-treatment in an upward flow anaerobic digester followed by a complementary treatment in an activated sludge system. The experimental research was carried out at the sewage treatment plant of the Pedregal neighborhood of the city of Campina Grande - Paraiba. It was verified that after the anaerobic pretreatment the efficiency of the activated sludge system (Bardenpho system) in the biological removal of nitrogen depended mainly on the relation between the concentration of the affluent nitrogenous material (TKN) and the organic matter concentration (COD ), ie the average TKN / COD ratio of the tributary. From the experimental data, an optimization model of the hybrid treatment system was developed in order to minimize treatment costs, obtaining a final effluent essentially free of suspended solids, BOD, nitrogen and phosphorus. It is concluded that in the hybrid system the costs of construction and operation are reduced by more than 50 percent when compared to the costs of the conventional Bardenpho system.