Rediseño del sistema de tratamiento de aguas residuales para la curtiembre Chimborazo ubicada en la ciudad de Ambato.

Abstract

A wastewater treatment system was redesigned for the Chimborazo Tannery located in the city of Ambato in order to comply with environmental regulations and obtain water treated with the parameters within the permissible limits of TULSMA, Official Registry, Ministerial Agreement No. 028 Table 9, Limits of discharge to a corps of freshwater. Because in the process of obtaining leather, the point where there is greater contamination of water is in the stage of tanning, from where three samples were taken for each month (January, February and March); the physical-chemical characterization allowed to identify the following parameters that are outside the range according to the Environmental Quality Standard for Effluent Discharge: pH, Turbidity, Suspended and Total Solids, Hexavalent Chromium, Biochemical Oxygen Demand and Chemical Oxygen Demand. It was proceeded to perform treatability tests by the jar test method with, aluminum polychloride (PAC) and anionic flocculants, for the regulation of Ph., lime was applied. When identifying the design variables, the equipment according to the physical-chemical treatments of the wastewater was dimensioned, which are: System of grids, Aeration Tank 1, Flocculation and coagulation tank, Rectangular settling tank, aeration tank 2 and filter of granular components. The selected design was validated with the results of the final characterization of the residual water and the average percentages of removal of the parameters of the three samples: Turbidity 99.46%, Suspended solids 99.78%, Total Solid 97.36%, Hexavalent Chromium 85 , 96%, Total Chromium 98.49%, Biochemical Oxygen Demand 99.06% and Chemical Oxygen Demand 98.25%. It is recommended to implement the wastewater treatment system, thus avoiding further discharge of contaminated water from the tanning stage.