Sistemas biológicos de tratamento de águas residuárias com biomassa suspensa e aderida :avaliação de parâmetros críticos e transição entre configurações : avaliação de parâmetros críticos e transição entre configurações

Abstract

In this work, the behaviour of biological systems in the treatment of synthetic wastewater simulating domestic sewage was investigated, addressing the relevance of some operational parameters in their performance, focusing on nitrification. In the 1st phase, the upgrade of a system with suspended biomass to MBBR configuration was evaluated, investigating the impact of the gradual reduction of the sludge age (stage without carrier media) and the increase in the media filling fraction (stage with carrier media) on the nitrifying activity. The minimum sludge age that allowed nitrification in the suspended sludge system was 8 h. With the gradual increase in carrier filling fraction, nitrifying activity was partially recovered, and ammonium removal reached up to 79.5% at 50% filling fraction. In the 2nd phase, the influence of hydraulic conditions on both microbial development and ammonium removal in MBBR systems subjected to the same applied load was evaluated. Higher nitrification levels were observed in the reactor subjected to higher HRT, a result associated with the possible biomass specialization, with the suspended sludge responsible for the removal of the organic matter, favouring nitrification in the biofilm. Despite showing lower nitrification performance, the reactor operated at lower HRT showed higher removal of load per biomass.