Tratamiento fisicoquímico de drenajes ácidos de roca (DARs) provenientes de las actividades de minería metálica en Ecuador

Abstract

Active and passive treatments are used as a cost effective option to treat acid mine drainage (AMD) through the use of physical, chemical or microbiological processes. These drainages are characterized by being highly acidic, in addition to presenting high concentrations of heavy metals that are toxic to the environment and living beings. The purpose of this study is the removal of metals and the neutralization of acidity of AMD obtained from Santa Rosa, El Oro province, for which this process will be validated through the design, assembly and operation of a continuous operation pilot plant, which involves physicochemical processes, it consists of the initial reactor where neutralization, aeration and coagulation take place, followed by the settler where the sludge is retained and finally, the sand/limestone filter. The average removal percentages were 100 percent iron, 99.94 percent copper, 100 percent arsenic, 94.06 percent cadmium, 99.66 percent manganese, 95.73 percent aluminum, and a final pH of 8.42, fulfilling all the parameters with the limits established for its release. The sulfate was not removed, however, it is below the maximum permissible limit for its release. From the results obtained, it is possible to demonstrate the effectiveness and importance of the assembly and operation of a pilot plant for the removal of metals and neutralization of acidity present in the acid drainage of mines in Santa Rosa, El Oro province.