Investigación integrada en laboratorio y campo sobre la utilización de residuos de alumbre, coagulantes inorgánicos y coagulantes naturales en el tratamiento de aguas residuales domésticas en humedales artificiales

Abstract

Wastewater treatment in rural areas poses a critical challenge due to the lack of adequate infrastructure, management policies, and environmental awareness, significantly impacting public health and water resources. This study evaluated a wastewater treatment system combining a septic tank for primary treatment, a coagulation system for secondary treatment, and a subsurface flow constructed wetland for tertiary treatment. The study also explored the use of alum residues, aluminum sulfate, and aloe vera as coagulants to enhance effluent quality. Jar tests were conducted to determine the optimal coagulant doses, followed by field application. Samples were collected in compliance with the INEN 2176:2013 standard at two key points: the wetland's outlet without coagulation and its outlet with coagulation. Physical-chemical parameters such as turbidity, BOD5, COD, nitrates, phosphates, ammoniacal nitrogen, and suspended solids, as well as microbiological parameters like fecal coliforms, were analyzed. The results revealed high removal efficiencies: turbidity (82%), BOD5 (78%), COD (79%), nitrates (78%), and suspended solids (83%). However, limitations were observed in phosphate and ammoniacal nitrogen removal, attributed to anaerobic conditions. This system offers a sustainable solution for wastewater management in rural communities. However, optimizing the system’s design is necessary to enhance nutrient and fecal coliform removal. Integrating complementary processes such as disinfection could further improve its efficiency, providing a more effective and sustainable approach to managing wastewater in underserved areas.