Geo-fluid analysis of the natural purification mechanism of Yotsugi mill tailings pond

Kawasaki, Yohei*; Granata, G.*; Tokoro, Chiharu*; Ohara, Yoshiyuki

no journal, , 

Arsenic in mine wastewater is an important issue in environmental research. In this study, to better understand the phenomena involved in the removal of arsenic from wastewater, the dynamic behavior of arsenic in the Yotsugi Mill Tailings Pond at Ningyo-toge mine was investigated. By utilizing geosphere fluid modeling software (GETFLOWS), we first reproduced the overall area flow through the advection-dispersion of non-reactive silicate ion with assuming the groundwater inlet. Following this, the total concentrations of arsenic and iron were reproduced by including in the previous advection-dispersion model, the first order kinetics for oxidation of As(III) and Fe(II) along with the precipitation equilibrium of Fe(III) as ferrihydrite. Finally, the adsorption of As(V) or As(III) on ferrihydrite was included in the simulation by considering the surface complexation model previously validated in batch adsorption tests. The results highlighted the natural oxidation of Fe(II) to Fe(III) and the subsequent precipitation of Fe(III) as ferrihydrite. Furthermore, the as-precipitated ferrihydride exhibited a strong ability to remove the arsenic by adsorption. The results also emphasized that the oxidation of As(III) to As(V) and the competitive adsorption between arsenic and the natural phosphates in water, play a key role in the natural removal of the arsenic in the pond.

Geo-fluid analysis for the natural purification mechanism of Arsenic and Iron in Yotsugi mill tailings pond

Kawasaki, Yohei*; Yagisawa, Makoto*; Fukuta, Hiroki*; Granata, G.*; Tokoro, Chiharu*; Ohara, Yoshiyuki

no journal, , 

Geochemical-fluid analysis for the natural purification mechanism of arsenic and iron in Ningyo-toge mill tailings pond

Kawasaki, Yohei*; Yagisawa, Makoto*; Granata, G.*; Tokoro, Chiharu*; Ohara, Yoshiyuki

no journal, , 

no abstracts in English