Propuesta metodológica de tratamiento pasivo basado en sustrato alcalino disperso para la remediación ambiental de metales pesados provenientes de drenaje ácido de mina

Abstract

A passive treatment is proposed using eggshells and MgO of technical grade, through the operation of a dispersed alkaline substrate (DAS) type filter system, for the environmental remediation of metals coming from an acid mine drainage (DAM). The first filter (DAS-Ca) had a composition of 25% (v/v) of eggshells and 75% (v/v) of wood chips, the second filter (DAS-Mg) contained 12,5% (v/v) of MgO and 87.5% (v/v) of wood chips. 1 L/day was treated with a retention time of 8 days. The DAM was characterized according to the following parameters: conductivity (2,67 mS/cm), total hardness (12,20 mg/L), calcium hardness (2,44 mg/L), pH (3,5), sulphates (1.900 mg/L), and sulfides (848 μg/L), Al3+ (19,23 mg/L), Co2+ (0,84 mg/L), Cu2+ (7,35 mg/L), FeT (412,50 mg/L), Fe3+ (180 mg/L), Fe2+ (232,50 mg/L), Mn2+ (10,45 mg/L), Ni2+ (0,62 mg/L), y Zn2+ (20,5 mg/L). The efficiency in metal removal that was obtained was the following: Al3+ (100%), Co2+ (95,8-98,7%), Cu2+ (97,6-99,3%), FeT (99,8%), Fe3+ (99,6%), Fe2+ (99,9%), Mn2+ (93-94,4%), Ni2+ (97,8-100%), y Zn2+ (90,6-99,8%). The MPL was complied with for discharges of fresh bodies were fulfilled on the TULSMA, Book VI Annex 1.