Evaluación de la eficiencia de remoción de DQO de un humedal artificial para el tratamiento secundario de los lixiviados del relleno sanitario Romerillos, cantón Mejía.

Abstract

In recent decades, the continuous growth of industrial production and trade has caused an increase in the world production of municipal and industrial solid waste, forcing the adoption of measures for its management, such as final disposal in landfills. However, this form of disposal releases a wide range of toxic compounds, such as leachates. To mitigate the negative impact of leachate on the environment, there is a need to investigate purification technologies passive to conventional treatment systems, such as artificial wetlands, which have shown a relationship between COD removal and retention time, being an important factor to evaluate. Research began with toxicological bioassays for the adaptation of plant species to be used in wetlands. It was evidenced that the species Iris pseudacorus and Phragmites australis tolerated 100% of the leachate, quite the contrary, Canna limbata tolerated a maximum concentration of 25% v/v. Based on the toxicological results, pilot artificial wetlands were adapted, with species tolerant to concentrated leachate and through an ANOVA test analysis, it was determined that retention times are directly proportional to COD removal, achieving efficiencies similar to those obtained with highly mechanized systems. Iris pseudacorus and Phragmites australis presented an average efficiency of 14,06 % and 14,88 %, respectively, with a TRH of 48 hours, and average efficiencies of 30,9 % and 19,5 %, respectively, with a TRH of 7 days. The unit without species reached its maximum efficiency (30,8%) at 48 hours of TRH, and with 7 days of TRH, its efficiency decreased to an average of 16,5 %.