Rediseño de un sistema de tratamiento de aguas residuales para la curtiduría San Vicente de la ciudad de Ambato.

Abstract

The objective was to redesign a wastewater treatment system for the “San Vicente” tannery located in the city of Ambato. The tannery San Vicente, has a deficient system of wastewater treatment, that is why the following study has as its first stage the current treatment system was assessed and then collected samples of the discharges of liming and tanning processes and to perform their respective analysis, it was determined that the main contaminants in the liming water are: BOD5, 12,500 mg / l; COD, 20 200 mg / L and sulfides, 1 620 mg / L while for the tanning water the following results were obtained: Cr6 +, 2, 10 mg / L; BOD5, 6 240 mg / L and COD, 12 750 mg / L. Through different tests of treatability tests, it was established that the optimal treatment for liming water is the oxidation of sulfides by a controlled aeration process and using MnSO4 as a catalyst, after this first stage we perform a chemical treatment by adding coagulant and flocculants to end with a sedimentation process that will be responsible for separating the contaminating sludge from the treated water. In relation to the tanning water, the treatment system begins with an alkaline stabilization process by adding lime to achieve a pH value of 8.5 so that the chromium precipitates, like a hydroxide, after this, it proceeds to perform a clarification treatment through a coagulation-flocculation process, to end with sludge sedimentation and respective separation of clarified water. Through these processes it was possible to obtain a yield greater than 90% in relation to removal of contaminants. Finally, the redesign of the WWTP was carried out through the respective modifications of the current system and the implementation of new treatment processes.