Estudio de un sistema combinado de tratamiento de aguas residuales de un camal a escala laboratorio con el uso de un filtro biológico y un proceso de oxidación avanzada.

Abstract

For this study, an aerobic biological treatment and a traditional Fenton process was applied at laboratory scale and through batch processing for the purification of wastewater at the Calacalí rural slaughterhouse. The effluents from the slaughtering, cleaning, and disinfection process were characterized. A removal of 58.6 % of oils and greases was achieved by using a grease trap treatment of the slaughtering process, and by means of a biofiltration system consisting of rice husks, humus, Californian earthworms (Eisenia foetida), stones and gravel, a removal of 89.3% of BOD5 was achieved. BOD5 removal in this system follows first-order kinetics with an optimum hydraulic retention time of 28 h, and achieved a removal of 89.4 % of COD, 81.5 % of TSS and 61.4 % of fecal coliforms. Through survival tests with earthworms, it was determined that the effluent from the cleaning and disinfection process was toxic to the living organisms in the biofilter. Therefore, a conventional Fenton process was studied at three different molar ratios based on a constant molar ratio (Fe2+/H2O2) of 0.4. It was determined that after an hour, at concentrations of 12.8 mM Fe2+ and 32 mM H2O2 respectively, the removals were 86.7 % COD, 76.8 % surfactants, 83.5 % TOC and a reduction of toxicity. The results indicated that a high proportion of the pollutants can be removed by the processes applied in this study.