Propuesta metodológica de indicadores de evaluación de sustentabilidad de sistemas de tratamiento de aguas residuales domésticas orientadas al sector rural

Abstract

It’s necessary to apply multicriteria strategies that evaluate in a comparative the performance of the WWTPs, and determine which(s) are the most suitable adjusted to our reality. Therefore, the main objective, was generating a methodological proposal for the evaluation by sustainability indicators applicable to WWTPs from ecuadorian rural sector. Results show that the best operational performance scenario was the IV, with average elimination percentages in Total Solids (TS) and Volatile Suspended Solids (VSS) of 34,6 and 49,5% respectively. While, in the Chemical Oxygen Demand removal (COD) was recorded average values of 66,2%. In terms of nutrients, this scenario showed a yield of 41%in Total Nitrogen elimination (TN). Scenario IV consumed more energy (42,42 kW-h/hab.año) and generates more sludge (0,66 m3/hab.año); in economic conditions, the highest operating costs (85,47 USD/hab.año); from the social point of view, scenario I show low percentages of coverage due to bad operation of these WWTPs Finally, the typologies that the best operation, environmental, economic and social conditions were two that bases on 4 stages of treatment that used constructed wetlands (P12 E-IV) and on 3 stages of treatment (P21 E-III).