Simulación computacional del post-tratamiento de lixiviados del relleno sanitario de Ambato mediante filtración subsuperficial en humedales artificiales

Abstract

Subsurface constructed wetlands of the horizontal type are applied as a profitable option for the purification of leachates both as treatment and post-treatment. An in silico investigation, using the COMSOL MULTHYPHYSICS version 5.4 software, allows to reduce total costs and time spent as much as possible, unlike an in vivo or in vitro investigation. The purpose of this study is to use the tools that the program provides, manipulate them in such a way that it adapts to reality through the use of physics that describe the flow at the entrance of the system, its behavior by Darcy's Law, surface reactions that involve kinetic and adsorption models, with the application of a series of parameters, constants and coefficients necessary to integrate the set of system of equations generated and to be able to solve with the help of the program. The removal percentages for organic matter were 72.15 and 90.06 for COD and BOD respectively, while for nutrients it varied between 60 and 75 percent, the bioaccumulation of heavy metals was also studied, obtaining the following percentages for lead 99.98, chromium 99.91, mercury 96.85, zinc 94.44, nickel 92.24 and cadmium 82.75, below these accumulation rates were copper with 57.30 and silver 56, however they complied with the regulations in force for their release. Based on the results obtained, the importance and effectiveness of the use of artificial wetlands for the purification of pollutants present in leachates is evidenced.