Estudo do comportamento hidrodinâmico de reator anaeróbio-aeróbio de leito fixo tratando efluente bovino

Abstract

The goal of this conclusion´s work course was evaluate the hydrodynamic behavior of anaerobic- aerobic in layer fixed operated at TDH of 24 h, 18 h and 12 h. It was used as a medium polyurethane foam and expanded clay, treating agroindustrial wastewater from slaughterhouse cattle. The reactor was operated at stand scale, with a volume of 4.75 L and kept in surround temperature. Were done hydrodynamic trials beyond testing stimulus-response type using tracer pulse eosin Y and bromophenol blue for evaluate the hydrodynamic behavior and anomalies. During the period of operation was carried out the monitoration of physic-chemical parameters such as temperature, dissolved oxygen, pH, alkalinity to bicarbonate, volatile acids, COD (aw and filtered), total solids and suspended solids to verify that the reactor was in a apparent state of dynamic equilibrium. The results of the hydrodynamics trials allowed to watch the phenomenon of the long tail when used the tracer eosin Y, now for the bromophenol blue was not so evident. This phenomenon is due to the spread of the tracer and its slow release in the effluent. In the calculation of dead zones negative values were obtained because of the existence of preferential paths. Still observed the presence of short circuit due to the real TDH be smaller than the theoretical, and some trials showed good hydraulic efficiency (λ ≥ 0,75). The model that best fit was N-CSTR, for all TDH and both tracers. DTR curves obtained with the N- CSTR model in series with the three TDH bromophenol bleu resulted in the best fit (average correlation of 0.972; 0.991 and 0.939 for the TDH of 24h, 18h and 12h respectively) with respect to eosin Y. Although it may be noted that the flow regime prevailing in the mixing RAALF is complete as found in a high longitudinal dispersion parameter D/uL models dispersion and the best fit of the experimental data for the model of complete mixing tanks in series.