Diseño de un vermifiltro para el tratamiento de aguas residuales domésticas a escala piloto

Abstract

In response to the growing challenge of combining efficiency, sustainability and low cost in wastewater treatment, vermifiltration emerges as a potential innovative and eco-friendly solution that combines operational simplicity, low costs and environmental benefits. To validate its applicability at real scale, it is essential to design pilot plants that allow for experimentation and optimization of critical variables such as substrate composition and organic and hydraulic loads, key factors for future system scaling. This article addresses the design of a pilot-scale vermifiltration system that enables the analysis of a wide range of such variables. It will be implemented at the Ucubamba Wastewater Treatment Plant complex in Cuenca, Ecuador. The system is designed for a population equivalent of 25 people, with an average flow of 3.75 m3/d. Its maximum treatment capacity, in terms of organic loading rate (OLR) is 0.25 kgDBO/m2, with a recommended maximum BOD concentration of 600 mg/L. The design includes four independent vermifilter cells, allowing individual effluent characterization. Each vermifilter column is composed, from top to bottom, of: 30 cm free space zone where the wastewater sprinkler is located, a 10 cm layer of worm compost, a 1 m active layer, 20 cm of pozzolanic material, 20 cm of gravel and 20 cm of whole stones. This design aims to ensure optimal conditions for microorganisms and worms, as well as flexibility to study both concentrated and diluted effluents, with the goal of thoroughly exploring a replicable alternative for wastewater treatment in rural and peri-urban areas of the region.