Remediación física, química y biológica de suelos contaminados por metales pesados a nivel de laboratorio

Abstract

Abstract: Mining in Ecuador is a key activity for the country's economic development, generating employment, but it also poses environmental and social challenges. This work proposed to study the efficiency of three methods of remediation of soils contaminated by heavy metals in the province of Azuay, canton Camilo Ponce Enríquez. Two plots were established, one control and one contaminated, where surface samples (0.30 m) and deep samples (1 m) were taken, following the guidelines of Ministerial Agreement 097-2015. The concentration of heavy metals such as cadmium, copper, chromium, manganese, nickel, lead and zinc was analyzed to verify compliance with the maximum permissible limit (MPL) of the Ecuadorian standard. The Q point of the contaminated plot was found to exceed the LMP for chromium, therefore, three remediation methods were applied: chemical treatment (washing with EDTA 0.05N), physical treatment (thermal desorption at 500 °C) and biological treatment (use of Sporosarcina pasteurii). The results showed chromium removal percentages of 92.67% (chemical), 98.82% (physical) and 61.04% (biological), concluding that all methods reached the LMP, with physical treatment being the most effective.