Diseño de un sistema de tratamiento de aguas residuales para la curtiduría Curtial de la parroquia Totoras – Tungurahua

Abstract

The purpose of this study was to design a wastewater treatment system for the Tannery "Curtial" because the effluent generated in the riverside stage is discharged into the sewer without proper treatment. For this, the sampling was carried out taking as a reference the point of discharge of the drums to subsequently carry out the physical-chemical characterization of the samples that allowed identifying the parameters that are outside the maximum permissible limits; obtaining pH 11.91, Suspended Solids 849 mg / L, Total Solids 2 220 mg / L, Sulfides 449 mg / L, Sulfates 950 mg / L, Biochemical Oxygen Demand (BOD5) 8 400 mg / L and Chemical Oxygen Demand (COD) 20 100 mg / L. Based on the data obtained, the biodegradability index was found to establish the type of treatment to be applied in the treatability tests, obtaining a value of 0.42 corresponding to a physical-chemical and / or biological treatment, which begins with a primary sedimentation process. Subsequently an oxidation process in the presence of air and 100 ppm of manganese sulfate used as a catalyst, thus reducing the amount of sulfides. Then a coagulant-flocculant treatment where it was determined that by dosing 250 ppm of aluminum sulfate and 10 ppm of anionic polyelectrolyte the maximum removal of turbidity is obtained, then a secondary sedimentation process and finally a filtration, achieving validation of the design based on the results obtained in the characterization of the treated water, having the following removal percentages of the main parameters: 93.51% of sulfides, 93.15% of BOD5 and 94.90% of COD, complying with the parameters established with the aforementioned current environmental standard. Consecutively, the design calculations were made taking advantage of the tanks that the company has and adapting the grids to the existing channel.