Remoção de matéria orgânica e determinação de parâmetros cinéticos em sistemas alagados construídos em escala laboratorial

Abstract

The objective of this study was to evaluate the performance of constructed wetland systems (SACs) for treatment of swine wastewater (ARS) under different organic loads (TCOA), and obtain kinetic parameters for sizing of the SACs. The SACs consisted of two tanks measuring 0.40 x 0.10 x 0.15 m, constructed of glass and filled with a 0.13 m layer of pea gravel; these were installed within a BOD incubator to maintain a 20°C temperature. The SACs were not cultivated and were submitted to average TCOA concentrations of 246 (SAC1) and 328 kg ha-1 day-1 of BOD (SAC2) for 51 days. With regard to the removal of organic matter, in the form of TSS, BOD and COD, no statistical difference was verified (p > 0.05) between the SACs, being that the average removal efficiencies for the referred variables in SAC1 and SAC2 were 68 and 76%, 66 and 73%, and 55 and 58%, respectively. The models proposed by Brasil et al. (2007) and Kadlec and Wallace (2008) presented good fit and adequately described the kinetics of organic matter removal (BOD and COD) from the evaluated systems, generally presenting R2 greater than 99%.