Evaluación de un sistema de biofiltración a escala laboratorio empleando como medio filtrante astillas de madera de ciprés para tratar aguas residuales municipales

Abstract

This project uses cypress wood chips shavings as support material in biofiltration systems at laboratory-scale, with the propose of valuing the effect of the particle size and the filtering material height in the removal efficiency of Chemical Oxygen Demand (COD), Biochemical Oxygen Demand (BOD₅), Total Suspended Solids (TSS) and Fecal Coliformes (CF). Also this project helps to corroborate if these systems comply with the regulations of Environmental Protection Agency of United States for reuse wastewater in the irrigation of crops commercially and the Ecuadorian environmental regulations for the use of water in irrigation. Six biofilters was ensambled with three particle sizes (¾”, ½” and ⅜”) and two heights (0.45 and 0.60 m). The biofilters were filed with water of Machangara River with a continuous flow under gravity action. Wastewater and water of biofilter effluents were sampling weekly, in order to determinate the removal efficiency for each analyzer parameter. The cypress wood chips with the highest removal efficiency were the ones packed in the biofilter B6. The average percentage for B6 were 65.26 ± 1.47 % of COD, 83.29 ± 4.00 % of BOD₅, 75.96 ± 4.19 % of TSS and 99.58 ± 0.46 % (2.47 logarithmic units) of FC. The results of this biofilter show that the effluent doesn’t comply with the national and international regulation for CF.