Diseño de un sistema de tratamiento de aguas residuales y su reutilización en el proceso de lavado en la Lavandería Splendid de la ciudad de Riobamba.

Abstract

The present research work was carried out to minimize contamination and reuse the water from the washing process in the SPLENDID laundry in Riobamba city. The collection of composite samples was carried out, as well as the physical-chemical and microbiological characterization of the wastewater. The parameters were analyzed based on the permissible limits of Table N°8; Limits of Discharge to the Public Sewage System, of Ministerial Agreement 097-A. Annex 1 of Book VI of the Unified Text of Secondary Legislation of the Ministry of the Environment: Environmental Quality and Effluent Discharge Standard to Water Resources. The characterized effluent obtained: Chemical Oxygen Demand (COD) 1240 mg/L; Biochemical Oxygen Demand (BOD5) 536 mg/L; Phosphates 85 mg/L; Surfactants 222 mg/L. The value of the biodegradability index is 0.43 which establishes a physical-chemical treatment system. The processes used were by aeration, coagulation-flocculation, aluminum reagents, aluminum polychloride, and ferric chloride were also applied, to obtain the optimal dosage for water treatability. The variables identified allowed the design of the wastewater treatment system, which consists of a landfill, grids, homogenizer tank, aeration tank, and a coagulation-flocculation tank. The results of the treated water: COD 225 mg/L with a 78.54% removal percentage; BOD5 115 mg/L with a 79.44% removal percentage; Phosphates 2.5 mg/L with a 97.06% removal percentage; Surfactants 1.8 mg/L with a 99.19% removal percentage. It was validated at ESPOCH Water Quality Laboratory and at UNACH Environmental Services Laboratory too. It was accredited by the Ecuadorian Accreditation Service (SAE). And it is concluded that the proposed design is reliable for its execution.