Diseño de un sistema de tratamiento de aguas residuales para el cantón Archidona de la provincia de Napo.

Abstract

This research is intended to design a wastewater treatment station for Archidona from Napo province in order to diminish the environmental impact arisen from the direct wastewater discharges into the river Misahuallí. The point of final wastewater discharge was inspected at first for a 7-day consecutive period from 06:30a.m – 18:00p.m in order to measure the wastewater flow which accounts for 5,81 liters. Afterwards, this control covers compound sampling carried out in 3 time-tables corresponding to 07:00a.m, 12:00a.m and 18:00p.m which let to ensure a representative flow sampling for the biological and physical and chemical characterization. The analysis results reflected substance values such as Oxygen Chemical Demand (DQO) 391 mg/L, Oxygen Biochemical Demand (DBO) 304 mg/L, Oils and Greases 37, 2 mg/L, Ammonia Nitrogen 45,5 mg/L, Tensoactive Substances 1,8 mg/L, Sedimentable solid 3,16 mg/L, Fecal Coliform 1X10 6 UFC/100 ml, which are very high and which exceed limits of norms laid down in the unified text from secondary environmental regulations (TULSMA). Thus, the necessity to have an appropriate system for the wastewater treatment in Archidona was real need; therefore the wastewater treatment station of this study proposal was stated from these parameters, it consist of a catchment water conduit, grilles, a degreaser devise, four wetland devises for superficial flow which are like those used for German grass (Echinochloa polystachya), a Parshall canal for the Polychloride of aluminum dosification, sedimentation and finally for filtration. This wastewater treatment station design allows to reach removal levels which were reflected in percentages as follow: DQO 93,18%, DBO 94,85%, Oils and Greases 78,5%, Ammonia Nitrogen 98,07%, Tensoactive Substances 70,6%, Sedimentable solid 96,84%, Fecal Coliform 99,9%, Turbidity 92,03%, which evidence that the treatment purposed from this study proposal is reliable. Therefore it is advisable for the Archidona Municipality to implement this wastewater treatment station to prevent the Misahuallí river pollution.