Evaluación de biofiltros para el tratamiento de aguas residuales de una granja pecuaria

Abstract

The Irquis Farm at the University of Cuenca is highly interested in characterizing its livestock wastewater and providing appropriate treatment to contribute to environmental protection and public health. Therefore, this study analyzed the main physical, chemical, and microbiological parameters of the farm’s wastewater. Additionally, three types of biofilters were designed and tested at the laboratory scale: one made of inert material, another made of coconut fiber, and a third composed of coconut fiber enriched with microorganisms (Bacillus subtilis and Aspergillus niger, which are dominant microorganisms in the livestock wastewater). The filtration systems operated with a flow rate of 27 cm3/min and filtration rates of 5.76 m3/m²d for the inert material biofilter, and 5.13 m3/m²d for the coconut fiber and coconut fiber with microorganisms biofilters. The results showed high values of TSS, turbidity, COD, BOD5, Cu, Cr6+, and total and fecal coliforms, while concentrations of Cd and Pb were not significant. The biofilters significantly reduced color, turbidity, TSS, and Cr6+, and improved dissolved oxygen (except for the coconut fiber with microorganisms biofilter), while maintaining appropriate pH and temperature ranges. However, Cu concentrations did not decrease significantly, remaining outside the limits of Ecuadorian regulations. These results are crucial for developing remediation strategies to improve the quality of livestock wastewater in the Irquis area.