Vermifiltración para el tratamiento de aguas residuales domésticas usando fibra de coco como sustrato

Abstract

The limitations in accessing conventional sanitation in various rural areas of the country open up new opportunities for the treatment of domestic wastewater through alternative systems, such as vermifiltration. The objective of this study was to evaluate the efficiency of a pilot vermifilter used for domestic wastewater treatment, employing coconut fiber as a substrate. To this end, two treatment systems were implemented: a soak pit used as a reference treatment and the treatment under study (vermifilter), in which the thicknesses of the coconut fiber were varied, using 15 cm and 30 cm, respectively. Additionally, both systems were operated with a hydraulic load of 0.12 m³/m²*day. The results obtained demonstrate that the vermifilter, with the inclusion of earthworms, significantly improves the quality of the treated water, achieving a higher removal of contaminants compared to the traditional soak pit. The best treatment was obtained with VF2, achieving removal rates for COD and BOD of 55.8% and 56.4%, respectively, while nitrate removal was 39.97%, ammoniacal nitrogen 59.65%, and total nitrogen 48.06%. Therefore, it is inferred that the thickness of the coconut fiber directly influences the efficiency of the process to maximize the removal of contaminants present in untreated water. Finally, the developed procedures manual provides a detailed guide for the proper operation and maintenance of the vermifilter under study.