Avaliação da não idealidade de biorreatores tipo lagoa com inserção de chicanas

Abstract

In the current brazilian contexto, in which it presents a deficit as the collection and treatment of sewage, the implementation of low cost and operational simplicity alternatives is critical. The intensive Livestock generates wastewater with high organic load, resulting in several impacts, case there is no previous treatment appropriate to release in water bodies. In real reactors, there are several anomalies, which non-ideal models seek to incorporate, for a more consistent prediction with reality. The use of baffles in pond-type reactors search approach the hydrodynamic behavior to the piston flow, corresponding to PFR reactor, to reduce the volume needed for an equivalent conversion. In the present study, the experimental runs were performed in a prototype anaerobic lagoon reactor coated with 8 mm PVC geomembrane, with a typical geometry for application in the treatment of swine manure, for residence times corresponding to 3, 6, 9 and 12 days, with use of 2 vertical baffles. Theoretical expressions for RTD were applied based on the dispersion model, and the prediction power for each expression was evaluated from the parameters obtained experimentally and from the adjusted parameters through a nonlinear optimization. The models evaluated were the low intensity dispersion model, the open-open system model, the semi-open system model and the closed-closed system model. The open- open system model considering the parameters obtained from the non-linear adjustment was the one that presented the best correlation coefficients adjusted for all the experimental runs. The application of the proposed model assists in a more precise design of anaerobic pond type reactors, when inserting parameters that are not usually used. Ignoring the effects of scale, this methodology can be applied for the design of similar reactors.