This paper addresses the evaluation of the application of unconventionalmethods to the treatment of leachates contaminated with heavy metals,products of the uncontrolled disposition of steel dust on soil. For thedevelopment of the methodology presented in this manuscript, columnsof glass (6 cm diameter) were filled with 15 cm of steel dust on top of 50 cmof soil. The columns were irrigated with constant fluxes of waterequivalents to the average precipitations of the Ecuadorian Highlandregion (0.15 mL/h). To avoid the “wall effect”, fiberglass (6 cm diameter, 0.8mm thickness) was located on the solid, in order to distribute the wateruniformly throughout the transversal section. Samples of the generatedleachates were collected weekly for four months to determinate the heavymetal content. Thereby, it was found that the effluents exceeded themaximum Ecuadorian limits for concentrations of chromium and arsenicthat may be discharged into freshwater bodies. Afterwards, the followingdepuration methods of the obtained liquid were employed: (i)Stabilization of the polluted leachate with Portland cement and lime, (ii)depuration of the contaminated liquid with a combination of theelectrocoagulation and phytoremediation processes, and (iii)recuperation of economically valuable attractive metals with electrolysisprior to the leachate treatment by conventional methods. The preliminaryeconomic evaluation of each procedure resulted in operating costs of US$401.74, US$ 1.57 and US$ 11.84 respectively. However, the low concentrationof heavy metals, organic matter and zinc in the leachates generated bysteel powder and percolated through soil does not justify the applicationof the treatment methods considered in this work, and it is recommendedto use conventional techniques.
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